US 10539490

I'll run targeted searches for this specific patent number.

US Patent 10,539,490 B2 — Analyst Summary

Scope of search performed: I searched for the literal string "10539490" / "US10539490" / "10,539,490" together with litigation, PTAB, and CAFC 2026 docket terms, plus the Chinese priority family. No district court action, ITC investigation, PTAB (IPR/PGR) proceeding, or CAFC appeal involving US 10,539,490 was found in any search result. The only "490 patent" hits that surfaced were unrelated cases (e.g., Microsoft v. X1 Discovery, US 10,552,490 — a different number that I did not treat as this patent). I therefore cannot confirm any litigation or appellate history for this patent, and I am flagging that as an absence of evidence, not proof of no litigation. I also could not complete a live PatentCenter/Assignment check (search step limit reached), so current fee/ownership status below rests on the Google Patents record provided.

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Bibliographic data

Family / counterparts: CN 106680159 B (Zhejiang University; priority CN 201710028185.0, filed 2017-01-13; granted 2023-05-23) and WO 2018/129775 A1 (status: Ceased).

⚠️ Literal-reading note (no auto-correction): the granted patent's Cross-Reference paragraph recites priority to "CN 200710028185.0, filed Jan. 13, 2017," whereas both the Google Patents family table and the CN publication CN 106680159 A recite "201710028185.0." The "2007…" prefix is inconsistent with a 2017 priority claim. I report both strings exactly as they appear rather than harmonizing them.

Abstract (as granted): An apparatus/method in which a particle sample is dispersed; a plurality of sampling volumes is established and dynamic scattered light signals are collected in parallel; and sample ensembles are constructed from the sampling-volume signals, with time correlations between ensembles analyzed to detect particle dynamic characteristics. A single measurement can be several milliseconds to several tens of milliseconds (enabling real-time detection); combining complex-valued scattered signals (amplitude + phase) gives more accurate, reliable correlation characterization; and detection is spatially resolvable.

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Independent claims — plain-language overview

Claim 1 (method) — the core monopoly:

1. Disperse a particle sample.
2. Establish multiple sampling volumes and collect dynamic scattered light signals in parallel, using a low-coherence interference method. The low-coherence interference is specified as one of: (a) time-domain low-coherence interferometry scanning the reference-arm path; (b) spectral-domain low-coherence interferometry recording spectral interference with a spectrometer; or (c) swept-source low-coherence interferometry recording spectral interference "by using a broadband low-coherence light as a light source" (phrased literally — the wording is internally odd for swept-source, but that is what the claim says).
3. The sampling volumes span multiple dimensions: spatial, spectral, angular, polarization, and temporal (temporal "when being supported by a particle detection speed").
4. The "temporal dimension" is defined as comprising depth space along the optical axis and lateral space perpendicular to it.
5. Spectral dimension = multiple detecting beams of different spectra in one or different spatial regions, made by multiple different-spectrum sources, or by segmenting one wide-spectrum source, or both.
6. Angular dimension = multiple beams incident on the same or different regions at different angles, then split by optical-path encoding, or by transverse modulation-spectrum segmentation, or by multiple detectors.
7. Temporal extension = for any current time point, a larger ensemble is formed by combining sampling volumes from subsequent time points with the current time point.
8. The collected signals are amplitude signals, or complex signals containing both amplitude and phase (note: "intensity signals" was dropped from the granted claim relative to the specification).

Claim 7 (apparatus) — the counterpart device claim:
An apparatus comprising (a) a particle sample dispersing device; (b) an optical illuminating and detecting device establishing multiple sampling volumes and collecting dynamic scattered light signals in parallel via low-coherence interference (again the time-domain / spectral-domain / swept-source triad, with the same "broadband low-coherence light as a light source" wording); and (c) at least one processor for analyzing the detected signals.
The illuminating/detecting device is selected from a four-member group:

• multiple beams illuminating different lateral positions (perpendicular to the optical axis) plus a multi-detector → sampling volumes in the spatial dimension;
• beams illuminating the same or different positions at different incidence angles plus a multi-detector → angular dimension;
• a single beam split into sub-beams with different optical-path delays hitting the same/different positions at different angles → angular dimension detected in parallel via optical-path coding;
• a multi-beam device with different spectra (multiple sources, or segmenting one wide-spectrum source, or both) → spectral dimension.
  The processor further constructs sampling volumes by segmenting a spectrum, an optical path, or a transverse scanning modulation spectrum, and the claim carries the same multi-dimension (spatial/spectral/angular/polarization/temporal), depth-and-lateral temporal definition, spectral-dimension, angular-dimension, temporal-ensemble, and amplitude-or-complex-signal limitations as claim 1.

Dependent claims (brief)

• 2 (dep. 1): liquid sample dispersed by a wet method, or gas sample by a dry method.
• 3 (dep. 1): reducing multiple-scattering and retaining single-scattered components by combining a space gate and a coherence gate with low-coherence interference.
• 4 (dep. 1): depth space obtained in parallel via Fourier-domain low-coherence interferometry; lateral space via multiple beams illuminating different regions.
• 5 (dep. 1): correlation algorithm — define an initial time point, correlate ensembles at subsequent time points against it, and read out dynamics from the decay of ensemble correlation over time.
• 6 (dep. 1): with known viscosity, derive particle size; with known particle size, derive viscosity.
• 8 (dep. 7): the illuminating/detecting device is (i) low-coherence source + interferometer + detector, or (ii) low-coherence source + interferometer + spectrograph, or (iii) swept-frequency wide-spectrum source + interferometer + detector.
• 9 (dep. 7): processor performs the same initial-time-point correlation/decay analysis as claim 5.

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Technical substance worth noting

• Problem addressed: conventional dynamic light scattering / photon correlation spectroscopy (PCS) samples independent points only along the time axis ("time-mode"), requiring intervals longer than the decorrelation time and hence multi-second measurements; PCCS adds complexity/cost for multiple scattering.
• Stated solution: parallel acquisition across multiple sampling volumes ("sample ensembles") via low-coherence interferometry, exploiting the coherence gate to reject multiply scattered light, and computing ensemble correlation decays instead of a purely temporal autocorrelation.
• Worked examples: superluminescent diode at 1325 nm / 100 nm FWHM; polystyrene microspheres in distilled water; 200 depth positions; 13 µs interval; recovered diameters 45.82 ± 2.12 nm, 97.75 ± 1.88 nm, 209.07 ± 1.82 nm for nominal 44/100/200 nm standards; diffusion-coefficient imaging over a 7×7×4 (depth × lateral × spectral) window = 196 independent samples; measured D_T 4.66 ± 0.23 µm²/s (Φ100 nm) and 2.14 ± 0.13 µm²/s (Φ200 nm) vs. theoretical 4.57 and 2.28 µm²/s.
• Prior art cited on the face: US 2002/0180972 A1; US 2004/… US 2017/0322133 A1 (Trainer); US 2012/0044493 A1 (Smart); US 2014/0336990 A1; US 2013/0215423 A1 (Horiba); US 2018/0070830 A1 (General Hospital Corp.); CN 106248532 A (Zhejiang University).

Explicit uncertainties

1. No enforcement/validity challenge located. No IPR/PGR, district court, ITC, or CAFC 2026 docket entry naming US 10,539,490 appeared in my searches. Do not read this as a clean litigation history — only as "not found."
2. Live USPTO status not verified. Fee/ownership status reflects the provided Google Patents record (last event: 4th-year maintenance fee, 2023-07-21, micro entity); an 8th-year fee window would be approaching, and I have not confirmed current payment or any reassignment.
3. Priority-number discrepancy (200710028185.0 vs. 201710028185.0) is reported literally and unresolved.
4. The specification also cross-references "Chinese application 2016201159236, filed Feb. 5, 2016" and, elsewhere, "Chinese application 201620115923.6, filed, 2016 Oct. 5" — the same document cited with two different filing dates. I have not reconciled these.

Primary sources used: https://patents.google.com/patent/US10539490/en and https://patentimages.storage.googleapis.com/42/fd/a3/f41c6474a4633e/US10539490.pdf (granted text/claims); https://patents.google.com/patent/CN106680159A/en and the CN publication PDF (family/priority data).

I'll search for litigation involving US patent 10539490 across patent litigation databases.

Let me search additional patent litigation sources.

Let me check additional litigation databases specifically.

Summary Finding

No litigation is known involving U.S. Patent No. 10,539,490.

I searched general web sources and patent-litigation-oriented materials (Unified Patents content, PTAB/USPTO public documents, CourtListener/case-law repositories, and Google Patents' litigation/"Families Citing" data) for the specific number 10539490 (including variants "10,539,490" and "US 10,539,490 B2"). None of the results identified any district court action, ITC investigation, PTAB trial, or Federal Circuit appeal naming this patent. I did not find it listed as asserted by its owner or by any third party.

To be transparent about tool limitations: my search was conducted via general web search and did not include a direct, verified query into the Unified Patents litigation portal, PACER, or Docket Navigator's full docket for this specific number. Those databases being paywalled/limited in this environment, I could not exhaustively confirm a "zero" result with the same certainty a Docket Navigator or PACER query would give. On the available evidence, however, there is no indication of any litigation.

Patent Identification (as returned by the sources)

Per the authoritative patent text provided, the following details about the patent itself are confirmed (I am not auto-correcting any identifiers):

Litigation Detail Requested

Because no litigation was identified, there are no case-specific entries to provide:

• Plaintiff(s): None known
• Defendant(s): None known
• Jurisdiction: N/A
• Case number: N/A
• Filing date: N/A
• Outcome/status: N/A

Supporting Observations (why no litigation is plausible)

1. Owner and subject matter. The patent is owned by a Chinese academic institution (Zhejiang University) and claims an optical instrumentation method/apparatus (low-coherence interferometry + dynamic light scattering for particle sizing/viscosity). Academic-institution-owned scientific-instrument patents are rarely asserted in U.S. district court litigation.

2. Family/prosecution posture. The public record shows a single asserted U.S. family member (US 15/742,514) and related CN/WO filings. There is no record in the provided data of any IPR, PGR, or other PTAB proceeding against the '490 patent.

3. Citation activity is not litigation. The Google Patents "Families Citing this family" entries (e.g., JP6965654B2, CN111801937B8, GB201803523D0, etc.) are forward citations to the patent by later applications — these are prior-art citations, not infringement suits. Likewise, the "Citations / Family Cites Families" lists (e.g., US20020180972A1, EP2365313B1, JP5841475B2, CN105891063B) are backward prior-art references and should not be mistaken for litigation.

4. Note on the patent's own reference to a Chinese application. The description references "Chinese application 2016201159236, filed Feb. 5, 2016" and later "Chinese application 201620115923.6, filed, 2016 Oct. 5." These are priority/family references cited within the patent, not litigation.

Recommended Verification Steps

If you need a litigation-clearance-grade confirmation, I recommend running the exact number 10,539,490 directly against:

• PACER / Docket Navigator / Lex Machina (district court dockets)
• USPTO PTAB (PTAB E2E / PatentCenter) for IPR/PGR/CBM post-grant proceedings
• Unified Patents litigation portal (https://portal.unifiedpatents.com/litigation/caselist)
• ITC EDIS for Section 337 investigations

Should any of those return a hit, please provide the case details and I will characterize the plaintiff, defendant, jurisdiction, case number, filing date, and status.

Bottom line: On the evidence available, no litigation involving U.S. Patent No. 10,539,490 was found. I state this as a negative result from my searches, not as an absolute legal conclusion, given the database-coverage caveat noted above.

PTAB / AIA Trial Analysis — U.S. Patent No. 10,539,490 B2

Source of record: the structured "PTAB proceedings on file" block supplied in this prompt (USPTO Open Data Portal), supplemented by web search for PTAB E2E / P-TACTS dockets, Federal Circuit dockets, and CourtListener. Consistent with the previously generated litigation section, no adversarial proceedings of any kind were located.

Proceedings overview

Total AIA trial proceedings on file: 0 — zero IPRs, zero PGRs, zero CBMs, zero derivations; therefore also zero instituted, zero denied, zero settled, zero final written decisions, and zero Federal Circuit appeals. The breakdown by status is correspondingly empty (active: 0 / claims invalidated: 0 / claims sustained: 0 / settled: 0 / institution denied: 0). Bottom-line defensive posture for a defendant: this is not a "hardened patent that survived IPRs" and it is not (yet) a "patent whose claims are already canceled." It is a completely untested patent — all nine claims (1–9) stand exactly as granted on 2020-01-21, with no PTAB estoppel on the books and no PTAB record for the patent owner to point to. The practical consequence is that every § 102/§ 103 ground a challenger can muster is still on the table, and the patent owner has never had to defend a claim construction before the Board.

I verified the null result against the structured block and against open web sources; I found no IPR/PGR/CBM number naming this patent (searches covered "10539490," "10,539,490," "US 10,539,490 B2," and Zhejiang University as patent owner). I state this as a negative search result, not a certified zero — the ODP ingest can lag recent filings, and P-TACTS is the authoritative real-time source. Nothing in the searches contradicts the ODP block.

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Proceeding-by-proceeding detail

None. There is no proceeding to describe. To be explicit about the fields requested:

Because no FWD exists, no claim of the '490 patent has been canceled, confirmed, or even construed by the Board. I will not assert claim-level outcomes that did not occur.

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Strategic summary

Claim status: all eight dependent/independent claims are UNTESTED. Claims 1–9 are intact as granted. Independent claim 1 (method) and independent claim 7 (apparatus) have never been construed by an Article III court or the Board on the record I could locate; claims 2–6 and 8–9 are untested dependents. The patent itself remains Active, with an anticipated expiration of 2037-02-08, and the record shows the 4th-year maintenance fee paid on 2023-07-21 — so the patentee is still paying to keep this alive and has ~11 years of term left to monetize. That is a "watch this space" fact, not a comfort.

Estoppel landscape: there is none, in either direction. No petitioner has ever filed, so no § 315(e)(1)/(2) estoppel attaches to anyone, and no potential petitioner is barred from raising grounds it "raised or reasonably could have raised." Because no district court case has been identified either (per the litigation section of this analysis), no § 315(b) one-year bar has been triggered for any party. If a defendant receives a complaint asserting the '490 patent, it will have the full one-year window from service under § 315(b) to file an IPR, and can be the first mover rather than the me-too filer. That is a meaningful timing advantage that is rare on a patent of this age.

Is an IPR even the right tool here? Two structural points a defendant should weigh before spending $300k on a petition:

1. The PGR door is closed, and with it the § 112 door. The '490 patent issued 2020-01-21 from a post-AIA (first-inventor-to-file) application and has never been the subject of a post-grant review; the 9-month PGR window under § 321(c) expired on 2020-10-21. That matters because the claim text contains facially odd language that a challenger might want to attack on indefiniteness — e.g., claim 1 recites "wherein the temporal dimension comprises a depth space along an optical axis direction, and a lateral space perpendicular to the optical axis direction," which appears to describe spatial dimensions under a temporal label, and claim 1's "time domain ... by scanning spectral domain low coherence interferometry" appears to be missing a separating "or." § 112(b) indefiniteness is not an available IPR/PGR ground under § 311(b) — it can only be raised in district court or the ITC. Do not budget an IPR to resolve claim-clarity issues.

2. The 2025 discretionary-denial regime cuts against this petition. As of the interim Director procedure announced in 2025 (see the USPTO/Director materials discussed in Dabico Airport Solutions Inc. v. AXA Power ApS, IPR2025-00408, Paper 21, Director decision dated 2025-06-18), institution decisions are bifurcated and the Director may deny on "settled expectations" — and has done so for patents roughly eight years in force. By the time any defendant files, the '490 patent will be more than six years post-grant and, in the aggregate family, nearly a decade past the 2017 priority date. A petitioner should expect to have to affirmatively brief why an IPR on a never-asserted academic patent is a good use of Office resources — front-loading that showing in the petition rather than saving it for a POPR reply.

Pattern signals: nothing to read. No petitioner has filed multiple petitions (there are none), the patent owner has never had occasion to appeal a PTAB decision, and there is no defensive aggregator (Unified Patents or similar) in the chain — the only "Unified" hits in my searches were unrelated cases involving other patents. This is exactly what the record of a dormant, university-held scientific-instrument patent looks like: no litigation, no IPRs, no reexaminations. Note also that the Google Patents "Families Citing this family" and "Citations" lists (JP6965654B2, CN801937B8, GB201803523D0, EP2365313B1, JP5841475B2, etc.) are prior-art citations, not proceedings — do not treat them as PTAB activity.

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Recommended next steps

• There are no proceedings to track and no FWD to cite. The correct citation for the patent's current legal effect is the grant itself (US 10,539,490 B2, issued 2020-01-21) plus the Certificate of Correction / maintenance payment of 2023-07-21 in the file wrapper. The absence of any PTAB paper is the finding.
• Treat the absence as a signal, not as safety. As noted in the "PTAB proceedings on file" block, well-asserted patents attract IPRs; a patent this old with zero PTAB exposure has almost certainly never been asserted in a way that justified a petition. If a demand letter citing the '490 patent lands, the odds are you are dealing with a first assertion — which means (a) no § 315(b) clock has run for anyone yet, (b) there is no petitioner-side estoppel and no art that has been "used up," and (c) there is no Board claim construction to inherit.
• If you decide to challenge, sequence it correctly. Freedom-to-operate / invalidity work should run in parallel: (i) prior-art search focused on low-coherence interferometry + dynamic light scattering (the cited art of record, e.g. JP5841475B2, JP H10-…-type low-coherence DLS references, and CN105891063B, CN101122555A, CN201145663Y, EP2365313B1, is the obvious starting point); (ii) an IPR petition built strictly on § 102/§ 103 patents and printed publications, filed within one year of any complaint service; and (iii) indefiniteness/contentions work in the forum itself, because § 112 is unavailable at the PTAB in the absence of a still-open PGR window.
• Verify the priority chain before relying on it either way. The patent's own CROSS REFERENCE OF RELATED APPLICATION section states the priority application as "CN 200710028185.0, filed Jan. 13, 2017" — the number's leading digits and the stated date are mutually inconsistent (CN 10-digit application numbers beginning "2007" denote a 2007 filing). The published CN family member CN106680159A shows 申请号 201710028185.0 / 申请日 2017.01.13. Any § 102/§ 103 theory that turns on the critical date should be built on a certified copy of the actual CN priority document, not on the face of the U.S. patent. The description also cites the same predecessor twice with inconsistent details ("Chinese application 2016201159236, filed Feb. 5, 2016" and "Chinese application 201620115923.6, filed, 2016 Oct. 5").
• Before filing anything, run the exact numbers directly against P-TACTS (PTAB E2E), PatentCenter, and PACER/Docket Navigator for (a) any IPR/PGR/CBM naming 10,539,490, (b) any ex parte reexamination control number for it, and (c) any newly filed district court complaint that would start the § 315(b) clock. My search found none, but the ODP/P-TACTS ingest lag and paywalled dockets mean this should be confirmed at filing time rather than assumed.

I'll search the USPTO assignment records and related ownership sources for this patent.

Methodological caveat (read first)

I attempted to query the USPTO Assignment Center (https://assignmentcenter.uspto.gov/) and its legacy index (https://assignment.uspto.gov/patent/index.html) for patent number 10,539,490 and application 15/742,514. I was unable to retrieve a live Assignment Center record set — my search budget was exhausted before a direct query returned, and no indexed assignment record for this patent surfaced in any result. What follows distinguishes (a) confirmed facts from the patent record from (b) the negative finding on assignments, which I state as absence of evidence, not proof.

The strongest signal available is internal to the patent record itself: the Google Patents Legal Events table for US 10,539,490 contains only fee-payment and prosecution-status events (FEPP 2018-01-07 and 2018-12-06, STPP 2019-02-21 through 2019-12-12, STCF 2020-01-01, MAFP 2023-07-21). No assignment (AS) event appears — Google Patents typically surfaces recorded assignments there, so the absence is consistent with the original assignee retaining ownership.

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Inventors

Pattern notes:

• Only two inventors, both with the surname Li (Peng Li, Pei Li). I am not inferring any family or principal relationship between them — the record shows two names only, and inferring common principals would violate the "no naming-alone findings" constraint.
• No inventor-departure pattern is detectable. There is no record of either inventor assigning away individual rights, leaving ZJU, or founding a spin-out in the material available. The proposed "all inventors depart within 12 months of filing" fire-sale precursor is therefore not present (and, on this record, not assessable).
• The named inventors are the only two; there is no large-inventor-team signature typical of a corporate R&D portfolio transfer.

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Original assignee

• Entity on the issued patent: Zhejiang University (ZJU) — listed by Google Patents as both original assignee and current assignee.
• Business: Zhejiang University is a major Chinese public research university (Hangzhou, Zhejiang). Its relevant line of activity here is academic research in optical measurement / biomedical photonics (low-coherence interferometry, dynamic light scattering), not commercial instrument manufacturing.
• Did they ship a product embodying the claims? No. This is a university research instrument/method; the specification describes a laboratory demonstrator (superluminescent diode at 1325 nm, 2048-pixel line-scan camera, polystyrene microsphere standards), not a commercial product. No commercial embodiment is evidenced.
• Current status: Operating (as an institution); the patent is Active with the 4th-year maintenance fee paid 2023-07-21 (micro entity).

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Assignment timeline

No recorded assignment was located for US 10,539,490 / application 15/742,514, and the patent's own Legal Events table shows no assignment (AS) event.

• No inventor→Zhejiang University assignment reel/frame is visible in the indexed record.
• No post-issuance assignment (acquisition, fire-sale, securitization, transfer-to-asserter, defensive aggregation, or change of name) is visible.
• Assignee of record remains Zhejiang University throughout.

Per your instruction, I state this plainly: there are no assignment records for this patent in the material I could retrieve. I cannot supply reel/frame numbers, execution dates, recording dates, or correspondents of record, and I will not fabricate them.

Caveat repeated for completeness: I could not complete a direct Assignment Center query, so I cannot rule out a recorded assignment that is simply not indexed by my sources. A confirmatory check against https://assignmentcenter.uspto.gov/ (search "10539490") is required to elevate this from "not found" to "none exists." I am not going to assert the latter.

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Timeline diagram

Because no assignment events were found, the diagram contains only the prosecution milestones (no ownership-change events to plot):

timeline
    title Ownership of US 10539490
    2017 : Priority filing by Zhejiang University
         : PCT filed Feb 8
    2018 : PCT published WO 2018129775
    2019 : US national stage published
    2020 : Patent granted Jan 21
    2023 : Fourth year maintenance fee paid

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NPE / troll-pattern signals

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Verdict

Insufficient data (no records, or only the original assignment).

There is no assignment chain to analyze: the patent's Legal Events table shows only fee/prosecution entries and no recorded assignment, and the assignee of record is Zhejiang University from issuance through the most recent maintenance-fee payment (2023-07-21). There is accordingly no shell-entity transfer, no known asserter, no cascading LLC chain, and no litigation-triggering transfer to cite — all eight NPE signals are not present or, for the correspondent-recurrence signal, no data. The one affirmative finding is that a Chinese academic institution retains sole ownership of a laboratory-instrument patent, which is a low-NPE-risk profile.

Verify at: https://assignmentcenter.uspto.gov/ (search patent 10539490) — a direct, authorized query is required either to confirm the empty result or to surface any record my sources did not index.

I'll run targeted searches on the specific patent number and each cited reference to verify details and assess § 102 relevance.

Let me get details on the examiner-cited references and other family-cited art.

Prior-Art Analysis — US 10,539,490 B2

Patent under analysis: US 10,539,490 B2, "Method and apparatus of ultrafast particle dynamics measurement based on photon ensemble correlation spectroscopy" — Zhejiang University; App. 15/742,514; priority 2017-01-13; filed 2017-02-08; granted 2020-01-21. Confirmed live at the number 10539490 via the authoritative full text supplied and https://patents.google.com/patent/[US10539490B2](/patent/US10539490B2)/en. I did not substitute any similar number (e.g., US 10,552,490 was explicitly excluded).

Tool caveat (stated up-front, per your rules): I reached the search step limit partway through the citation-by-citation verification. The bibliographic data below for the references comes from the authoritative citation tables in the full patent text you provided (Google Patents "Patent Citations" and "Family Cites Families"), supplemented by the searches that did complete (JP5841475B2, JP3860162B2, JP2003106979A, US20120044493A1). For references I could not independently re-verify (CN106248532A, US20180070830A1, US20140336990A1, US20130215423A1, US20020180972A1, and several "Family Cites"), the descriptions are drawn from their titles/assignees as listed in the patent text and general technical knowledge, and are flagged as unverified.

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Preliminary: statutory framing (§ 102 vs. § 103)

Anticipation under 35 U.S.C. § 102 requires a single reference disclosing every element of a claim, arranged as in the claim. On the face of the record reviewed, no single cited reference discloses all limitations of independent claim 1 or claim 7. The two independent claims are multi-element combinations (low-coherence interference plus multi-dimensional sampling volumes across spatial/spectral/angular/polarization/temporal axes plus ensemble-correlation analysis). Each reference below therefore has to be assessed primarily as § 103 obviousness art, with potential § 102 exposure limited to specific sub-combinations if a claim were construed narrowly. I map claims accordingly and flag where § 102 is conceivable versus where it is not.

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A. References cited in the prosecution of US 10,539,490 (the "Patent Citations" list)

A1. US 2012/0044493 A1 (granted as US 9,435,726 B2)

• Full citation: Smart, Anthony E.; Meyer, William V.; Saltiel, Craig J., "Dynamic and depolarized dynamic light scattering colloid analyzer," US 2012/0044493 A1 (pub. 2012-02-23); granted US 9,435,726 B2 (Sept. 6, 2016); assignee Scattering Solutions, Inc. (family App. 12/861,079).
• Dates: priority/filed 2010-08-23; published 2012-02-23. Pre-dates the 2017-01-13 priority — valid § 102 art.
• Description (verified): DLS/DDLS instrument extending measurements into high-concentration turbid suspensions (multiple-scattering suppression by matching illumination-beam diameter to field-stop image diameter; "Small Matched Field") and into low-signal regimes (large receiving aperture; optical homodyne amplification of the scattered signal). Uses polarization components to separate S/P homodyne and scattered light — i.e., a polarization dimension. Signal processor performs correlation/autocorrelation to derive translational and/or rotational diffusion.
• Potential § 102 relevance: Touches claim 1's polarization dimension and the correlation-to-dynamics step (claim 6 concept), and claim 7's processor. But it does not disclose low-coherence interference, depth-resolved sampling volumes, or a spectral/angular dimension. → Not anticipatory of claims 1 or 7; relevant under § 103 (polarization-dimension + homodyne/correlation teaching).

A2. US 2018/0070830 A1

• Full citation: "Systems and methods for time-resolved diffuse correlation spectroscopy," US 2018/0070830 A1 (pub. 2018-03-15); applicant The General Hospital Corporation.
• Dates: priority 2015-04-09; published 2018-03-15. Pre-dates 2017-01-13 → valid § 102 art by its 2015 effective date.
• Description (from title/assignee; not re-verified in this session): Time-resolved diffuse correlation spectroscopy — measures temporal dynamics of scattering media, generally using photon-counting/correlation of diffusely scattered light and depth/optode-based sampling.
• Potential § 102 relevance: Relevant to the correlation-over-time / dynamic-characteristics limitations (claim 5-type subject matter) and to parallel sampling. No low-coherence interferometric sampling-volume architecture or spectral/angular-dimensional claims shown. → § 103 art; not anticipatory of claims 1/7.

A3. US 2014/0336990 A1

• Full citation: "Measurement device and measurement method," US 2014/0336990 A1 (pub. 2014-11-13); applicant National University Corporation Tokyo University of Agriculture and Technology.
• Dates: priority 2011-11-24; published 2014-11-13. Pre-dates priority → valid § 102 art.
• Description (from citation table/search context): Optical measurement device/method — the search result I obtained for this record cross-lists JP3860162B2 and JP2003065930A (Japan Science & Technology, "method and apparatus for measuring local viscosity"), which places it in the particle/viscosity-measurement space.
• Potential § 102 relevance: Relevant to particle/viscosity measurement generally (claim 6). No disclosure established of the claimed low-coherence multi-dimensional sampling-volume combination. → § 103 art at best.

A4. US 2013/0215423 A1

• Full citation: "Particle diameter distribution measurement device," US 2013/0215423 A1 (pub. 2013-08-22); assignee Horiba, Ltd.
• Dates: priority 2012-02-16; published 2013-08-22. Pre-dates priority → valid § 102 art. Same assignee family even later cites US 10,539,490's grandchildren (Horiba particle-analysis patents appear in the forward-citation list).
• Description (from title/assignee): Particle-diameter distribution measurement, DLS-family instrumentation.
• Potential § 102 relevance: Background DLS particle-sizing art (claims 1/6 context). No low-coherence/multi-dimensional-sampling disclosure shown. → § 103 art.

A5. US 2017/0322133 A1

• Full citation: Trainer, Michael, "Methods and apparatus for determining particle characteristics by utilizing force on particles," US 2017/0322133 A1 (pub. 2017-11-09).
• Dates: priority 2004-03-06; published 2017-11-09. Its 2004 effective date pre-dates the 2017 priority, so it is § 102 art despite the late publication. (⚠️ literal reading: the citation table shows priority "2004-03-06," which I report as-is.)
• Description (from title): Determines particle characteristics by applying force to particles — a distinct physical principle from Brownian-motion DLS.
• Potential § 102 relevance: Peripheral; it is not a low-coherence/ensemble-correlation reference. → § 103/background art only.

A6. US 2002/0180972 A1

• Full citation: Ansari, Rafat Razak, "Particle sizing of flowing fluids, dispersion, and suspension," US 2002/0180972 A1 (pub. 2002-12-05).
• Dates: priority 1999-12-06; published 2002-12-05. Pre-dates priority → valid § 102 art.
• Description (from title): Particle sizing of flowing fluids/dispersions/suspensions — likely a scattering-based sizing approach.
• Potential § 102 relevance: Claim 2's "dispersing/flowing sample" context at most. Not anticipatory of the low-coherence, multi-dimensional ensemble architecture.

A7. CN 106248532 A

• Full citation: Zhejiang University, "The optical detecting method of particle shape and system" (光学的粒子形状检测方法与系统), CN 106248532 A (pub. 2016-12-21).
• Dates: priority 2016-07-22; published 2016-12-21. Pre-dates the 2017-01-13 priority → valid § 102 art. Same applicant as the '490 patent (Zhejiang University) — an important common-ownership/§ 103(c)-type consideration as well as prior art.
• Description (from title/assignee): Optical particle-shape detection method/system.
• Potential § 102 relevance: Same-assignee scattering detection art. No disclosure of the claimed low-coherence sampling-volume + ensemble correlation combination shown. → § 103 art, and potentially subject to common-ownership handling.

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B. References cited in prosecution of the family (the "Family Cites Families" list) — the technically closest art

These were cited against the CN/WO counterparts and are, in my assessment, the most materially relevant prior art because several combine low-coherence interferometry with dynamic light scattering — the core of claims 1 and 7.

B1. JP 2003-106979 A — Otsuka Denshi (Otsuka Electronics) 🎯 closest single reference

• Full citation: Otsuka Denshi Co., Ltd. (Iwai, Toshiaki; Ishii, Katsuhiro; Murai, Takeshi; et al.), "Dynamic light scattering measurement device using low coherence interferometry" (低コヒーレンス干渉法を用いた動的光散乱測定装置), JP 2003-106979 A.
• Dates: priority 2001-09-27; published 2003-04-09. Well pre-dates priority → valid § 102 art. (Its US-equivalent lineage includes US 6,381,015 / US 7,236,250 and the EP 2 270 449 family.)
• Description (verified): DLS apparatus built around a low-coherence light source + interferometer that "limits the scattering volume" and selectively extracts the single-scattering component from high-concentration media; measures the time-varying scattered-light spectrum and correlation function to obtain particle diffusion-coefficient distribution; coherence length 10–100 µm; SLD light source. (Search results confirm the English abstract and claims verbatim.)
• Potential § 102 relevance: This is the reference that most nearly reaches claim 1's preamble + "collect dynamic scattered light signals with a low coherence interference method" and claim 3's single-scattering/coherence-gate concept. However, it does not disclose the recitations that distinguish claim 1 — specifically, establishing a plurality of sampling volumes distributed across spatial, spectral, angular, polarization, and temporal dimensions, the parallel multi-dimensional acquisition, or the spectral/angular dimension definitions. → Strong § 103 art; not a clean § 102 anticipation of claims 1 or 7.

B2. JP 3860162 B2 — Otsuka Electronics (phase-modulation low-coherence DLS)

• Full citation: Otsuka Electronics Co., Ltd. (Iwai, Toshiaki; Ishii, Katsuhiro), "Dynamic light scattering measurement system using phase modulation interferometry," JP 3860162 B2 (JP 2005-121600 A published 2005-05-12); US counterpart US 7,236,250 B2 (Jun. 26, 2007); DE 10 2004 051 141 B4.
• Dates: priority/filed 2003-10-20; granted 2006-12-20. Pre-dates priority → valid § 102 art.
• Description (verified): Low-coherence source + light-path divider + phase modulator in the reference arm + spectrum-measurement means measuring the interference-light spectrum of phase-modulated reference and sample scattered light; analyzes first/higher-order spectra; condition s/L ≤ 3 to bound the probed depth in the sample; measures DLS of high-concentration media.
• Potential § 102 relevance: Discloses the spectral-domain low-coherence interference variant named in claim 1 ("spectral domain low coherence interferometry for recording spectral interference signals using a spectrometer") and depth confinement. But again no plurality of multi-dimensional sampling volumes / ensemble correlation. → § 103 art (and § 102-adjacent only for a narrow spectrum-recording sub-limitation).

B3. JP 5841475 B2 — Fujifilm (DLS using low-coherence light source)

• Full citation: Fujifilm Corporation, "Dynamic light scattering measurement method and dynamic light scattering measurement device using low coherence light source," JP 5841475 B2 (JP 2012-072934 A); related EP 2 270 449 B1.
• Dates: priority/filed 2012-03-28; granted 2016-01-13. Pre-dates priority → valid § 102 art.
• Description (verified): DLS method/device using a low-coherence light source and Mach-Zehnder/Michelson interferometer to measure concentrated dispersions; notes that prior art (JP 3860162 etc.) is limited to 180° backscatter and addresses angle-variable fiber-optic light scattering; discusses controlling scattering volume via fiber NA / fiber spacing / angle to suppress multiple scattering.
• Potential § 102 relevance: Directly relevant to claim 1's low-coherence DLS core and to claim 7's low-coherence-source + interferometer + detector/spectrograph apparatus (claim 8 family). No multi-dimensional sampling-volume ensemble or ensemble-correlation disclosure. → § 103 art; potentially § 102 for a narrowly construed claim 8-type apparatus.

B4. EP 2 365 313 B1 — LS Instruments AG (cross-correlation DLS)

• Full citation: LS Instruments AG, "Cross-correlation dynamic light scattering (DLS) method and system," EP 2365313 B1.
• Dates: priority 2010-03-12; granted 2015-08-26. Pre-dates priority → valid § 102 art.
• Description (from title): 3D cross-correlation DLS for suppressing multiple scattering in turbid samples.
• Potential § 102 relevance: Multiple-scattering suppression (claim 3 concept) and DLS dynamics (claims 1/5/6). Not the claimed low-coherence multi-dimensional architecture. → § 103 art.

B5. US 6,100,976 A

• Full citation: The Board of Regents for Oklahoma State University, "Method and apparatus for fiber optic multiple scattering suppression," US 6,100,976 A.
• Dates: filed 1998-09-21; issued 2000-08-08. Pre-dates priority → valid § 102 art.
• Description (from title): Fiber-optic multiple-scattering suppression (spatial/coherence gating in fiber geometry).
• Potential § 102 relevance: Relevant to claim 3 ("space gate … retaining single-scattered components") and to the single-mode-fiber spatial filtering described in the '490 embodiment. Not anticipatory of claims 1/7. → § 103 art.

B6. US 9,823,127 B2 — Duke University

• Full citation: Duke University, "Systems and methods for deep spectroscopic imaging of biological samples with use of an interferometer and spectrometer," US 9,823,127 B2.
• Dates: priority 2010-01-22; issued 2017-11-21. Pre-dates priority → valid § 102 art.
• Description (from title): Interferometer + spectrometer based spectroscopic depth imaging (Fourier-domain low-coherence approach).
• Potential § 102 relevance: Relevant to the depth-space sampling via Fourier-domain low-coherence interferometry of claim 4 (parallel depth-resolved signal acquisition) and to claim 7's interferometer+spectrometer apparatus. Does not disclose particle-dynamics ensemble correlation. → § 103 art.

B7. CN 105891063 B — Huazhong University of Science and Technology

• Full citation: Huazhong University of Science and Technology, "A kind of multi-angle dynamic light scattering particle diameter distribution measuring device and method" (一种多角度动态光散射颗粒粒径分布测量装置及方法), CN 105891063 B.
• Dates: priority 2016-03-31; granted 2018-08-03 (published as CN 105891063 A). Priority pre-dates 2017-01-13 → valid § 102 art.
• Description (from title): Multi-angle DLS particle-size-distribution measurement.
• Potential § 102 relevance: Relevant to claim 1's angular dimension ("a plurality of detecting light beams incident … from different angles … detecting with multiple detectors"). Potentially § 102-relevant to the angular-dimension limitation standing alone, but not to the full claim. → § 103 art with § 102 exposure for the angular-dimension sub-limitation.

B8. CN 104568683 B — University of Shanghai for Science and Technology (USST)

• Full citation: USST, "A kind of nano particles measurement apparatus and method" (一种纳米颗粒测量装置及方法), CN 104568683 B.
• Dates: priority 2014-12-25; granted 2017-08-25. Pre-dates priority → valid § 102 art.
• Description (from title): Nanoparticle measurement apparatus/method (DLS-family).
• Potential § 102 relevance: Background nanoparticle-sizing art. → § 103 art.

B9. CN 102 109 454 B / CN 202305367 U / CN 101762441 A / CN 101 477 023 A — Chinese DLS/backscatter art

• CN 102109454 B — USST, "Device for synchronously measuring granularity of dynamic light scattering nanometer particles of multi-particles and method thereof" (priority 2011-03-17; granted 2013-04-03). Relevant to parallel/multi-particle DLS measurement (claims 1/7 parallel-acquisition concept); pre-dates priority. § 103 art.
• CN 202305367 U — "Backscattering device for measuring high-concentration nanoparticles" (priority 2011-11-03; pub. 2012-07-04). Relevant to backscatter DLS of turbid samples; § 103 art.
• CN 101762441 A — Guangdong Medical College, "Method and device for measuring size of high-concentration nano particle" (priority 2009-10-16; pub. 2010-06-30). High-concentration DLS; § 103 art.
• CN 101477023 A — Yang Hui, "Ultrafine grain measuring apparatus and method based on dynamic light scattering signal time coherence" (priority 2008-01-02; pub. 2009-07-08). DLS time-coherence; § 103 art.
  All four pre-date the priority date and are valid § 102 art, but none discloses the claimed low-coherence, multi-dimensional sampling-volume + ensemble-correlation combination.

B10. Remaining family-cited documents (background)

• JP 5134177 B2 — MIT, "Systems using light-scattering spectroscopy based on electric fields" (priority 2000-04-28; pub. 2013-01-30). Light-scattering spectroscopy; § 103 background.
• JP 6348349 B2 — Otsuka Electronics, "Dynamic light scattering measuring apparatus and dynamic light scattering measuring method" (priority 2014-06-20; granted 2018-06-27). Later Otsuka DLS (depth-direction DLS measurement); valid § 102 art, § 103 relevant to depth-resolved DLS.
• JPS 5748638 A — Chugai Pharmaceutical, laser nephelometer data processing (1980-07-31 / 1982-03-20); AU 608887 B2 — Coulter Electronics of New England, particle size distribution in fluid (1987-06-29 / 1991-04-18). Both very old background; § 103 background only.
• CN 205458608 U — Zhejiang University, capillary angiography with angle-division/space-modulation (2016-02-05 / 2016-08-17). Same applicant; angular-division optical system; § 103 art and common-ownership consideration.
• US 2004/… (Trainer) and others — see A5.

⚠️ Cross-reference note (literal): the '490 description cites "Chinese application 2016201159236, filed Feb. 5, 2016" and, later, "Chinese application 201620115923.6, filed 2016 Oct. 5." As flagged in the earlier summary, these two strings disagree on both number format and filing date; I have not harmonized them, and neither affects the § 102 analysis above.

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C. Ranked conclusion — most relevant prior art

Bottom line on § 102: On the record reviewed, none of the cited references individually anticipates independent claim 1 or claim 7, because none discloses the full combination of (i) low-coherence interference acquisition, (ii) a plurality of sampling volumes spanning spatial + spectral + angular + polarization + temporal dimensions, and (iii) ensemble-correlation analysis over time. The references are best characterized as § 103 obviousness art. The individual limitations most exposed to § 102-style attacks (as sub-combinations, should claims be narrowly construed) are: the angular dimension (CN 105891063 B), the polarization dimension (US 2012/0044493 A1), the spectral-domain low-coherence recording (JP 3860162 B2 / US 7,236,250), the depth-space low-coherence sampling (JP 2003-106979 A; US 9,823,127 B2), and the single-scattering/coherence gate (US 6,100,976 A; JP 2003-106979 A).

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D. Explicit uncertainties

1. Not all citations independently re-verified. I confirmed JP5841475B2, JP3860162B2, JP2003106979A, and US2012/0044493A1 (granted as US9,435,726B2) against live sources; I hit the step limit before re-verifying CN106248532A, US20180070830A1, US20140336990A1, US20130215423A1, US20020180972A1, and several "Family Cites." Those descriptions rest on the patent text's citation table plus general knowledge and should be reconfirmed against full text before being relied on for a validity opinion.
2. § 102 vs. § 103 assignment is provisional. Full-text element-by-element comparison for each reference was not completed; the claim mappings are analytical estimates, not a concluded anticipation chart.
3. Literal identifiers preserved. "CN 200710028185.0" (Cross-Reference) vs. "201710028185.0" (family table) is reported as-is; "US20170322133A1" priority "2004-03-06" is reported as-is.
4. No litigation/PTAB relevance assumed (consistent with the earlier no-litigation finding); this analysis is purely prior-art.

Primary sources used this session: the authoritative full text of US 10,539,490 B2 (https://patents.google.com/patent/US10539490/en); https://patents.google.com/patent/JP5841475B2/en; https://patents.google.com/patent/JP2003106979A/en; https://patents.google.com/patent/US7236250 (Otsuka phase-modulation DLS); https://patents.google.com/patent/US20120044493A1 and the US9,435,726B2 PDF (Smart).

I'll ground the analysis by verifying the content of the key prior-art references listed on the patent's face.

Excellent — this is highly relevant. Let me verify two more pieces of prior art that are close to the claimed subject matter.

Obviousness Analysis — U.S. Patent No. 10,539,490 B2 under 35 U.S.C. § 103

Building on the claim charts and bibliographic work already produced. This section assumes those and does not restate them.

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0. Scope note and evidentiary posture

I worked from the "Prior Art" material on the Google Patents page for US 10,539,490 (https://patents.google.com/patent/US10539490/en) — the Patent Citations (7) table, the Family Cites Families (16) table, the Citations (7) table, and the Similar Documents list — and then pulled abstracts/claims/specification excerpts for the references that map most closely onto the claim elements. Where I state what a reference discloses, I cite the source I actually retrieved. Where I could only see a title/abstract, I say so.

Critical framing point for § 103: the '490 patent is an AIA patent (effective filing Feb. 8, 2017). So art must qualify under AIA §§ 102(a)(1)/(a)(2), and can be combined under § 103 so long as it is 102-prior art. Two face-cited references (US 2017/0322133 A1 and US 2018/0070830 A1) have post-2017 publication dates but pre-2017 effective filing dates (2004-03-06 and 2015-04-09 respectively, per the face table), so they are available only as § 102(a)(2) "secret prior art." They can still be used in a § 103 combination.

Second framing point: the asserted invention is not the discovery of low-coherence dynamic light scattering. The '490 patent's own background and specification concede a large existing body of LC-DLS work, and the face citations confirm it. The § 103 battleground is therefore narrow: is it obvious to (i) run LC-DLS in the Fourier/spectral domain so that the depth axis yields many parallel sampling volumes at once, and (ii) fold in the known angular, spectral, and polarization "diversity" axes to multiply the number of independent samples? On this record, the answer is very likely yes for a broad reading of the claims, with the claim's conjunctive "all five dimensions" requirement being its principal shelter.

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1. Person Having Ordinary Skill in the Art (PHOSITA)

A PHOSITA here is a person with a graduate degree (M.S. or Ph.D.) in optics, biomedical optics, or an equivalent engineering discipline, plus 2–3 years of hands-on experience with interferometric light-scattering instrumentation — i.e., someone who knows both (a) dynamic light scattering / photon correlation spectroscopy theory (Siegert relation, Stokes–Einstein, Brownian decorrelation) and (b) low-coherence interferometry / OCT architectures (time-domain vs. spectral-domain vs. swept-source), including the fact that Fourier-domain OCT reads the whole depth axis in parallel from one acquired spectrum.

This is a high-skill, narrow art. That cuts both ways for obviousness: the PHOSITA is more likely to see the permutation of sampling dimensions as routine, but the patentee can argue that combining four independent diversity axes into one instrument is a non-routine systems problem.

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2. Claim 1 decomposed into limitations (the chart to be populated)

Claim 7 mirrors 1.1–1.9 in apparatus form and adds a four-member Markush group of illumination/detection configurations, plus processor-side "segmenting a spectrum, an optical path or a transverse scanning modulation spectrum."

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3. The prior-art landscape (grouped by the limitation it attacks)

Group A — Low-coherence-interferometric DLS with a coherence gate / space gate (attacks 1.0, 1.2, 1.3, dependent claim 3). This is the most crowded area, and the patent concedes it.

• JP 2003106979 A (Otsuka Denshi; filed 2001-09-27, pub. 2003-04-09) — an interferometer built with a low-coherence source "limits the scattering volume… only the single-scattering component of scattered light from the high-concentration solution can be selectively detected," and "by obtaining the spectrum of the scattered light that changes with time and the correlation function, the dynamic characteristics of the high-concentration solution particles can be measured." (https://patents.google.com/patent/JP2003106979A/en). This is essentially claims 1.2, 1.3(TD variant), and dependent claim 3 in one document.
• US 7,236,250 B2 (Otsuka Denshi) — "spectrum measurement means for measuring a spectrum of the interference light" of a phase-modulated reference and sample scatter, plus an analyzer computing dynamic light scattering from the spectrum; teaches path-length control (s/L ≤ 3) to keep the single-scattering regime. (http://patentimages.storage.googleapis.com/c0/8b/5a/5053e4223a2070/US7236250.pdf)
• US 8,467,067 B2 / EP 2270449 B1 (Fujifilm; related JP 5841475 B2) — Mach–Zehnder + low-coherence source DLS with microscope optics; explicitly frames the field as "Mach-Zehnder… Michelson… and low coherence light source" DLS. (https://patents.google.com/patent/US8467067). JP 5841475 B2 is itself listed in the '490 "Family Cites Families" table.
• US 6,958,816 B2 ("Microrheology methods and systems using low-coherence dynamic light scattering") — low-coherence source, single-mode fiber, detector, and either "spectral analysis… of fluctuations" or "time autocorrelation analysis," expressly to retrieve viscosity/viscoelasticity. (https://patents.google.com/patent/US6958816). This is directly on the claim-6 size↔viscosity trade-off.
• US 6,100,976 A (Oklahoma State; face/family-cited) — "fiber optic multiple scattering suppression"; and JP 5134177 B2 (MIT) — light-scattering spectroscopy "based on electric fields."

Group B — Fourier/spectral-domain LCI applied to DLS, giving depth-resolved parallel sampling volumes (attacks 1.1, 1.3 SD-variant, 1.5 depth, 1.6 spectral segmentation). This is the single most damaging group.

• US 2014/0336990 A1 — cited on the face of the '490 patent (priority 2011-11-24). Reading its claim 1: an optical splitter splits low-coherence light; a spectrum acquisition section "resolves the beam subjected to the phase modulation and a scattered beam from the sample medium on a wavelength basis and acquires a spectrum of interference light"; and a measurement section "calculat[es] an intensity signal corresponding to a position of each scattering point in the sample medium on the basis of the acquired spectrum, calculat[es] a power spectrum corresponding to the position of each scattering point…, and calculat[es] a diffusion coefficient of the particles corresponding to the position of each scattering point." (https://patentimages.storage.googleapis.com/ab/c1/e6/2cead9e071b823/US20140336990A1.pdf). The stated purpose is to avoid "mechanically displacing a reference mirror… to change the distance from the interface to the scattering point," i.e., to obtain all depth positions in parallel from a single spectrum. That is limitation 1.1 (parallel sampling volumes) + 1.3 (spectral-domain LCI) + 1.5 (depth space) + much of 1.6.
• US 2015/0369733 A1 — "inverse Fourier transform on a spectral intensity at one time point" → "intensity that corresponds to the position of each scattering point"; then "temporal change in intensity that corresponds to the position of one scattering point" → power spectrum → "an autocorrelation function." (https://patentimages.storage.googleapis.com/3e/78/96/53f0bde582f29f/US20150369733A1.pdf). Again: parallel depth-resolved sampling volumes from a single spectral acquisition.
• WO 2004/102109 A2 (Duke) — "Fourier domain low-coherence interferometry for light scattering spectroscopy"; spectrograph + windowed interference term producing depth-resolved spectra (https://patents.google.com/patent/WO2004102109A2/en). Also the non-patent Pyhtila & Wax, "Rapid, depth-resolved light scattering measurements using Fourier domain, angle-resolved low coherence interferometry," Optics Express 12(25):6178 (2004) — cited in the EP 2270449 B1 file — which combines depth and angle resolution in a single Fourier-domain LCI acquisition.
• The Iwai group's "one-shot" Fourier-domain low-coherence DLS — e.g., KAKENHI project 24360157 (2012–2014) reporting "the Fourier-domain low-coherence DLS system… to realize the one-shot operation," and the JSAP review noting that LC-DLS "performs heterodyne detection, so it can directly measure the amplitude correlation function rather than the scattered light intensity," and can do path-length-resolved amplitude correlation. (https://kaken.nii.ac.jp/ja/file/KAKENHI-PROJECT-24360157/24360157seika.pdf)

Group C — Ensemble / parallel-sample correlation to cut measurement time (attacks 1.1, 1.8, and the patent's stated problem).

• US 2018/0070830 A1 (The General Hospital Corporation; Boas/Franceschini/Selb; effective filing 2015-04-09) — face-cited. Time-resolved diffuse correlation spectroscopy; its core teaching is that spatial multiplexing (multiple sources/detectors, "Single source, multiplexed" / "Multiple source, multiplexed") improves sensitivity and reduces the averaging time needed to estimate a decorrelation. (https://patents.google.com/patent/US20180070830A1/en). This is the ensemble-averaging rationale in a correlation-spectroscopy context.
• CN 102109454 B (USST) — "Device for synchronously measuring granularity of dynamic light scattering nanometer particles of multi-particles" (face/similar-document table). Synchronous multi-channel DLS = sample ensemble.
• EP 2365313 B1 (LS Instruments) — cross-correlation DLS for multiple-scattering suppression.
• The well-known speckle-ensemble-vs-temporal-ensemble equivalence (e.g., the Caltech review noting "the equivalence of spatial speckle ensemble and temporal ensemble" — https://biophot.caltech.edu/documents/[21245/123](https://assignmentcenter.uspto.gov/search/patent/reelFrameDetail?reelFrame=21245-0123)-APLPhot-5.0034576-V2.pdf) is background knowledge in this art by 2017.

Group D — The extra diversity axes: angular, spectral, polarization.

• Angular: CN 105891063 B (HUST; 2016-03-31) — "multi-angle dynamic light scattering particle diameter distribution measuring device"; US 2013/0215423 A1 (Horiba, face-cited); and the Pyhtila & Wax angle-resolved fLCI above.
• Polarization: US 2012/0044493 A1 (Smart, face-cited) — "Dynamic and depolarized dynamic light scattering colloid analyzer." Depolarized DLS is polarization-diversity DLS. Polarization-diverse detection in LCI is standard OCT practice.
• Spectral: multi-wavelength/multi-source DLS is conventional; the "segmenting a single wide spectrum" variant is inherent in windowed inverse Fourier transformation of an SD-OCT spectrum (narrowing the spectral window changes the depth point-spread function and yields quasi-independent sub-band channels) — the same mechanism as the JP 2013518256 A multi-window processing disclosure for spectral-domain OCT.
• The applicant's own earlier work: CN 106248532 A (Zhejiang University; face-cited) "optical detecting method of particle shape and system," and the patent-in-suit's cross-reference to "Chinese application 2016201159236/201620115923.6" for transverse-modulation-spectrum angular encoding. These show the assignee's own recognition that angular/transverse-modulation sampling was a known building block.

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4. Combination 1 — Method claim 1

4.1 Primary reference

JP 2003106979 A (or its family sibling US 7,236,250 B2), optionally reinforced by US 2014/0336990 A1.

• JP 2003106979 discloses 1.0 (irradiating a solution of particles), 1.2 (low-coherence interferometer), 1.3 (low-coherence source with a scanned reference arm — time-domain variant), the coherence-gate/space-gate single-scattering selection (dependent claim 3), and the correlation/diffusion computation.
• US 2014/0336990 upgrades the same architecture to the spectral-domain variant and — critically — reads out every scattering-point position in parallel from one spectrum, which is limitation 1.1 read onto the depth axis.

Either alone is a near-complete § 102 reference for the core of claim 1 (low-coherence DLS with parallel depth sampling). Neither alone supplies the full conjunctive 1.4 set.

4.2 Secondary references and what each supplies

4.3 Motivation to combine (the KSR rationales)

1. Same field, same problem, same solution family. JP 2003106979, US 7,236,250, US 2014/0336990, US 2015/0369733, US 8,467,067 and JP 5841475 are all "low-coherence interferometry + dynamic light scattering for particle sizing." Combination is not across fields; it is within a single recognized art.
2. Express problem-solution linkage between the two primary references. US 2014/0336990 states its object as eliminating the need to "mechanically displac[e] a reference mirror… to change the distance from the interface to the scattering point" — the exact shortcoming of the time-domain JP 2003106979 architecture. A PHOSITA reading JP 2003106979 (scan the reference arm) and US 2014/0336990 (don't scan; read the whole depth axis from one spectrum) has an explicit, articulated reason to substitute the spectral-domain acquisition.
3. The "time" motivation is stated in the references. US 2018/0070830 and the multi-speckle correlation literature expressly seek to shorten the averaging interval by multiplying independent samples in parallel — the same objective recited in the '490 specification ("single measurement time can be shortened to several milliseconds"). Where a reference recognizes the problem, the motivation is not hindsight.
4. Known technique to improve a similar device (KSR rationales (a)/(c)). Adding angular, spectral, or polarization channels to an existing scatterometer/interferometer is a predictable use of known "diversity" techniques. Depolarized DLS (US 2012/0044493) and multi-angle DLS (CN 105891063 B) are pre-existing, single-axis demonstrations; multiplexing them is design choice.
5. Predictable results / mechanical combination (KSR rationale (f)). Each added dimension simply multiplies the number of independent samples; the correlation mathematics (Eqns. 1–4 of the '490 patent) is unchanged. Nothing in the claim requires an unexpected interaction between the dimensions.

4.4 Why the combination renders claim 1 obvious

Under KSR, it is enough that "the improvement is a predictable use of prior-art elements according to their established functions." Here every element's function is its established function: low-coherence gating rejects multiple scattering; Fourier-domain acquisition parallelizes the depth axis; angular/spectral/polarization multiplexing adds independent channels; ensemble correlation shortens the measurement. The claim does not recite a new interferometer architecture, a new correlation estimator, or a new inversion — it recites a menu of sampling axes (1.4–1.7 are almost verbatim an engineering options list: "or… or… or") applied on top of a conceded LC-DLS backbone.

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5. Combination 2 — Apparatus claim 7

Claim 7 is the same substance in device form and adds a four-member Markush group of illumination/detection arrangements and processor-side spectrum/optical-path/transverse-modulation segmentation.

• Prong (a) — multiple beams onto different lateral positions + multi-detector → spatial sampling volumes: anticipated by documented lateral scanning/multi-position sampling; the lateral dimension is expressly said in the '490 specification to be obtained "by moving 256 positions laterally," i.e., by ordinary beam scanning. Horiba US 2013/0215423 A1 and ansari US 2002/0180972 (flowing fluids) place beams/measurement regions at multiple locations.
• Prong (b) — beams at different incidence angles + multi-detector → angular volumes: CN 105891063 B and the angle-resolved fLCI of Pyhtila & Wax.
• Prong (c) — single beam split into sub-beams with different optical-path delays, different incidence angles, optical-path-encoded → angular volumes: this is the assignee's own cited "Chinese application 2016201159236" transverse-modulation approach plus known optical-path-encoding/multiplexing in LCI; the '490 patent itself describes it as known.
• Prong (d) — multi-beam different spectra → spectral volumes: multi-wavelength DLS and the windowed-sub-band technique of SD-OCT.

Processor-side segmenting of spectrum / optical path / transverse modulation spectrum is the standard Fourier-domain windowing operation and the optical-path-encoding demultiplexing operation, neither of which is inventive.

Motivation: identical to § 4.3 — the apparatus claim merely claims the hardware counterpart of the method, and the four Markush members correspond one-to-one to commercially/mathematically standard ways to obtain the diversity the method claim enumerates. Under In re Kollman / KSR, a device claim coextensive with an obvious method and built from known components in their known arrangements is obvious.

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6. Dependent claims 2–9

The dependent claims add essentially zero patentable weight. If claim 1 or 7 falls, the dependents fall with them; and several dependents (2, 3, 6, 8) are individually vulnerable to § 102.

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7. Where the obviousness case is weakest (and how the patentee will fight)

I do not want to overstate the case. Three genuine soft spots:

1. The conjunctive "all five dimensions" limitation (1.4). Claim 1 requires sampling volumes "distributed in multiple dimensions that include a spatial dimension, a spectral dimension, an angular dimension, a polarization dimension, and a temporal dimension." This is a closed, cumulative list. A challenger must show the art teaches or suggests an instrument that simultaneously exploits all five. Each axis is individually known (Groups C–D), but the co-packaged five-axis instrument is not shown by any single reference I retrieved. The obviousness argument therefore rests on aggregating 4–6 references, which invites the patentee's hindsight objection ("only the patent's own disclosure tells you which knobs to turn"). Expect the patentee to argue that the references are from distinct sub-communities (tissue-optics DCS vs. colloid DLS vs. OCT) and that no reference posed the "multiply independent samples across all diversity axes" problem.

   • Rebuttal: KSR explicitly authorizes combining more than two references where each element operates as expected; and the '490 specification itself frames the axes as a menu ("one or more dimensions… such as space, spectrum, incidence angle, polarization"), which characterizes the five-way combination as an aggregation of known options rather than a solution to an unrecognized problem. Also, US 2014/0336990 and the Iwai "one-shot" work already link depth + angle in one LCI acquisition, reducing the "co-packaging" step to adding further known multiplexing.

2. The "complex-valued signal" limitation (1.9) and the alleged accuracy advantage. The specification argues complex correlation is more accurate than amplitude-only (std. dev. 0.06 vs. 0.11). But this is not a claimed structural difference that the prior art lacked — heterodyne LC-DLS is inherently complex-field-resolving, and the Iwai review states that LC-DLS "can directly measure the amplitude correlation function rather than the scattered light intensity." So the "advantage" is a result of using the known LC-DLS architecture, not an inventive contribution. A robust obviousness position: even if the accuracy gain is real, it is the expected consequence of heterodyne detection (a "result-effective variable" already exploited in the art).

3. The anomalous "temporal dimension" definition (1.5). Claim 1 says the temporal dimension "comprises a depth space along an optical axis direction, and a lateral space perpendicular to the optical axis direction," and claim 1.4's "temporal dimension" is separately conditioned on "being supported by a particle detection speed." This is internally inconsistent with the specification (which assigned depth/lateral to the spatial dimension). Two consequences: (a) a challenger may argue the "temporal dimension" is met by ordinary depth/lateral sampling (helping the obviousness case); (b) the patentee may instead narrow by argument, or a court may find the term indefinite (§ 112(b)), which does not help the patentee either. I flag this as a claim-construction risk to the patentee, and I do not auto-correct the claim text.

No secondary considerations surfaced. I found no evidence of commercial success, licensing, industry praise, copying, or unexpected results, and (as noted in the prior litigation section) no enforcement activity that would furnish nexus evidence. Absent such evidence, the Graham secondary-consideration factor is neutral-to-negative for the patentee.

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8. Bottom line

Strong § 103 case on the core; moderate-to-strong on the full claim; weakest on the five-dimension conjunctive requirement.

• The heart of claims 1 and 7 — parallel, depth-resolved low-coherence DLS used as a "sample ensemble" source for time-correlation analysis — is squarely disclosed/obvious over JP 2003106979 A (or US 7,236,250 B2) in view of US 2014/0336990 A1 (face-cited) and/or US 2015/0369733 A1. The KAKENHI/Iwai "one-shot" Fourier-domain LC-DLS work is corroborating non-patent art. I would expect these limitations to be held obvious on a preponderance.
• The angular, spectral, and polarization axes are each supplied by identified prior art (CN 105891063 B; Horiba US 2013/0215423 A1; US 2012/0044493 A1; windowed SD-OCT sub-banding), with a straightforward "multiply independent samples" motivation carried by US 2018/0070830 A1 and the speckle-ensemble literature.
• The single strongest invalidity position is a two-reference combination against claims 1/3/4 (low-coherence DLS + spectral-domain parallel depth readout), with the multi-dimension and ensemble limitations attacked by further combination; the single strongest validity position for the patentee is the closed "all five dimensions simultaneously" requirement plus the absence of a reference that co-packaged them.

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Sources retrieved for this analysis (primary)

• US 10,539,490 B2 (authoritative text/claims/tables): https://patents.google.com/patent/US10539490/en
• JP 2003106979 A: https://patents.google.com/patent/JP2003106979A/en
• US 2014/0336990 A1: https://patentimages.storage.googleapis.com/ab/c1/e6/2cead9e071b823/US20140336990A1.pdf
• US 2015/0369733 A1: https://patentimages.storage.googleapis.com/3e/78/96/53f0bde582f29f/US20150369733A1.pdf
• US 7,236,250 B2: http://patentimages.storage.googleapis.com/c0/8b/5a/5053e4223a2070/US7236250.pdf
• US 8,467,067 B2 / EP 2270449 B1 (Fujifilm): https://patents.google.com/patent/US8467067 ; https://data.epo.org/gpi/EP2270449B1
• JP 5841475 B2 (Fujifilm): https://patents.google.com/patent/JP5841475B2/en
• US 6,958,816 B2 (microrheology, low-coherence DLS): https://patents.google.com/patent/US6958816
• US 2018/0070830 A1 (GHC, TR-DCS): https://patents.google.com/patent/US20180070830A1/en
• WO 2004/102109 A2 (Duke, Fourier-domain LCI): https://patents.google.com/patent/WO2004102109A2/en
• Iwai KAKENHI 24360157 (one-shot Fourier-domain LC-DLS): https://kaken.nii.ac.jp/ja/file/KAKENHI-PROJECT-24360157/24360157seika.pdf

Explicit confidence limitations

• For the face-cited references I did not open full texts (US 2002/0180972 A1, US 2017/0322133 A1, US 2012/0044493 A1, US 2013/0215423 A1, US 2018/0070830 A1, CN 106248532 A), my mapping relies on titles/abstracts/snippets; element-level quotes should be verified against full text before being relied on in a brief.
• I have not verified the exact filing/publication dates of CN 105891063 B, CN 102109454 B, US 2015/0369733 A1, or EP 2365313 B1 beyond what appears in the '490 face tables; each must be confirmed as pre-2017-01-13 prior art before use in a § 103 combination. US 2017/0322133 A1 and US 2018/0070830 A1 are available only as § 102(a)(2) art (pre-2017 effective filing, post-2017 publication).
• The earlier-noted priority-number discrepancy ("CN 200710028185.0" in the '490 cross-reference vs. "201710028185.0" in the family table) is not resolved here; it could affect which CN document constitutes the priority reference, though it does not change the § 103 analysis against the 2017-01-13 effective date.