US 11320254

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Summary of US 11,320,254 B2

Important sourcing note: The authoritative full text of this patent (including title, bibliographic data, abstract, and description) was supplied in the message above and is the basis for the summary below. Two items deserve explicit flagging:

1. The claims section was not included in the supplied patent text (it was truncated within the Detailed Description). My plain-language claim overview is therefore derived from the specification's Abstract and Summary of the Invention, not from verbatim claim language. I cannot confirm exact claim numbering or precise claim scope.
2. No CAFC 2026 docket or USPTO litigation/PTAB record tied to patent number 11320254 was found in my searches. Searches for this number returned the patent itself (Google Patents/Wikidata) plus unrelated hits that merely share the digits — e.g., a UK company registration number (HARRANDBASS LTD), a payroll line item, and a PubMed accession — none of which relate to this patent. I found no evidence of any Federal Circuit appeal, IPR, or district-court case involving it. This does not prove no such proceeding exists; it means I have no authoritative confirmation of one.

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Bibliographic data (per supplied text)

Representative CPC classifications: G01B 11/02; G01B 11/026; G01B 11/14; G01B 9/02032 (spatial carrier frequency); G01B 9/0209 (low-coherence interferometers); G01B 9/02002 / 9/02007 (two or more frequencies); G01J 9/02; B23K 26/032 (observing/monitoring a workpiece by optical means); B23K 26/702; G01B 2290/45; G01B 2290/70 (polarization).

Abstract

A method and system for determining the separation distance between an object (e.g., a workpiece) and a processing or measuring tool. A measurement beam of low-coherence optical radiation is directed at the object and the reflected beam is led to an optical interferometric sensor assembly along a first direction of incidence. A reference beam of the same low-coherence radiation is led to the sensor assembly along a second direction of incidence. The two beams are superimposed on a common region of incidence, and the position of the interference fringe pattern along an illumination axis is detected. The difference in optical length between the measurement optical path and the reference optical path is derived from that fringe position, yielding the current separation distance between tool and object.

Plain-language overview of the independent claims (inferred — see caveat above)

Based on the specification, the patent appears to claim the following subject matter:

• Method claim — Determining the separation distance between an object/material and a processing or measuring tool by: generating a low-coherence measurement beam; conveying it through the working head to the object and returning the reflected/diffused beam to a photodetector sensor array in a first incidence direction; generating a low-coherence reference beam and directing it to the sensor array in a second incidence direction at a predetermined angle to the first; superimposing both beams on a common sensor region to form an interference fringe pattern; detecting the fringe envelope's position along the illumination axis; and computing the measurement-vs-reference optical path-length difference from that position to obtain the current separation distance (relative to a nominal standoff). The distinguishing point is that the beam incidence angle is set so the fringe spatial frequency exceeds the photodetector (pixel) spatial frequency — i.e., an intentional sub-sampling/aliasing condition (preferably near a half-integer multiple, e.g. k_f/k_p ≈ 1.5, or 2.5, 3.5, 4.5) that is exploited to extend the measurable range rather than treated as an error.

• System claim — An interferometric system configured to carry out the above method, comprising: a low-coherence source (LED/superluminescent diode, linearly polarized); a beam splitter producing the measurement and reference beams; a measurement optical path (polarization-maintaining fiber) at least partly integrated in the working head and emerging at the tool/beam-output end; a reference optical path with a reflective return element (optionally including an optical density filter, dispersion compensation element, λ/4 plate, and focusing lens); a sensor array of photodetectors arranged along an illumination axis; and processing means configured to identify the fringe pattern and its position. Reflective elements direct the two beams onto the sensor's common incidence region at a controllable angle.

• Machine-tool claim — A machine tool (processing a piece/material) incorporating such a separation-distance determination system, operating in predetermined processing regions (including mechanical-cutting and fluid-nozzle variants shown in FIGS. 5b–5c).

• Laser-processing-machine claim — A laser processing machine (cutting, drilling, welding, or additive manufacturing) incorporating the system, with the measurement path emerging at the laser beam output or assist-gas nozzle (FIGS. 4, 5a).

Dependent claims, per the specification's discussion, likely add: the detector array being linear (or 2-D) with cylindrical-lens concentration; specific demodulation steps (background normalization; high-pass filter ≈ 1/5 of pixel frequency; absolute value; low-pass filter ≈ 1/25 of pixel frequency; peak-finding or Gaussian model fit); the nominal standoff mapped to a mid- or end-position of the fringe envelope; use of a λ/4 plate to orthogonally rotate the reference polarization; polarizing beam-splitter separation with a λ/2 plate; and a dichroic mirror plus piezoelectrically controlled scanning mirror to place the measurement spot ahead of, behind, or coaxially with the processing region.

Key technical/utility framing from the specification

• Chosen technique is low-coherence interferometry with spatial-domain detection (vs. time- or Fourier-domain), described as fastest to demodulate with economical linear image sensors and robust to optical noise from the laser process.
• Reported performance: translating the fringe envelope across the illumination axis gives a measurable standoff range of roughly 0.25 mm to 2 mm (~1.8 mm range) at k_f/k_p ≈ 1.5, versus ~0.3 mm without aliasing (k_f/k_p ≈ 0.3); at k_f/k_p ≈ 4.5, ranges on the order of 5 mm are indicated; sensitivity given as 1.5 µm/pixel.
• It is positioned as an improvement over prior-art capacitive standoff sensing (FIG. 1), which is limited to conductive/metallic workpieces and suffers edge/curvature compensation problems.

Uncertainty statement

I do not have authoritative verbatim claim text for US 11,320,254 (the claims were absent from the supplied material), and I found no CAFC 2026 docket, PTAB proceeding, or district-court case associated with this patent. Any statement here about claim scope is an inference from the Abstract/Summary and should be verified against the granted claims on USPTO Patent Center or Google Patents before being relied upon.

I'll research litigation involving US Patent 11,320,254 across patent litigation databases and court records.

Let me search more specifically for this patent in litigation databases and check the assignee.

Let me check the Unified Patents litigation portal and PTAB for any proceedings involving this patent.

Findings: Litigation Involving U.S. Patent No. 11,320,254

Result: No litigation (or PTAB/IPR proceeding) involving U.S. Patent No. 11,320,254 was found.

What I searched and what I found

I searched patent-litigation sources (Unified Patents–style litigation coverage, PACER/CAFC-adjacent indexes, and general docket aggregators) using the specific number 11320254 and the '254 shorthand. No case was found in which U.S. 11,320,254 is an asserted or challenged patent.

Key distinguishing facts about the patent that confirm the "no results" conclusion:

Important disambiguation — results that mention a "254" patent but are NOT this patent

My searches surfaced several unrelated references to a "'254 patent." These involve different patents and should not be confused with US 11,320,254:

• Samsung counterclaim (DJ of invalidity of the '254 patent) — a Samsung Electronics counterclaim referencing a '254 patent alongside '952, '019, '600, '127, '129, '816 patents in a case brought by a party abbreviated "SEVEN." The subject matter and co-asserted patents do not match the Adige optical-interferometry patent.
• Arbutus Biopharma litigation and EPO oppositions referencing an Arbutus "'254 Patent" (nucleic-acid lipid particle technology related to COVID-19 mRNA vaccines) — clearly unrelated.
• Heron Therapeutics v. Azurity and other pharma dockets listing 12,115,254 — a different number.
• Harrandbass Ltd — UK company number 11320254 (a corporate-registration hit, not a patent).

None of these correspond to US 11,320,254 (Adige SpA).

Caveats

• This conclusion is based on publicly indexed search results available to me. Private settlements, recently filed (unpublished) complaints, and non-English dockets could exist but would not necessarily appear.
• The patent is relatively new (granted 2022-05-03) and held by a machine-tool manufacturer (Adige SpA, part of the BLM/Adige laser-cutting group), which is not a typical patent-assertion-entity profile — consistent with the absence of assertion litigation.
• To verify definitively, I would recommend querying PACER directly (all district courts) and the USPTO PTAB "Patent Trial Appeal Board" API/PatentCenter for the application number 17/110,419, and checking Unified Patents' patent page for 11320254. I was unable to complete those final targeted queries within the allotted search budget.

Bottom line: As of the available data, there is no known litigation involving U.S. Patent No. 11,320,254.

I'll verify the structured data with targeted searches before drafting.

Let me run additional targeted checks on the assignee and inventors to see whether any AIA trial exists under a different name.

Proceedings overview

Total AIA trial proceedings on US 11,320,254: 0 (0 active, 0 claims invalidated, 0 claims sustained, 0 settled, 0 institution denials). The USPTO Open Data Portal ("PTAB proceedings on file" block) returns no IPR, PGR, or CBM tied to this patent as of the most recent ingest, and my independent web checks surfaced nothing to the contrary — so the defensive posture is "no PTAB attack has ever been filed, which means the claims are entirely untested before the Board and every AIA ground remains open to you as a first mover." This is the opposite of the "patent survived two IPRs and is hardened" scenario: it is a virgin patent, procedurally, and the absence of prior Board treatment also means there is no § 315(e)(2) estoppel and no Board claim-construction record to constrain either side.

Source of record: the structured ODP block supplied with this task. No proceeding number appears anywhere in this report because none exists — I will not manufacture one.

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Proceedings

There are no proceedings to itemize. For completeness, here is the negative result stated in the same fields the itemization would have used:

(none) — no petitioner v. Adige S.p.A.

• Type: n/a — no IPR, PGR, or CBM on file
• Filed: n/a
• Status: n/a (ODP reports no AIA trial proceedings for this patent)
• Judge panel: n/a — no panel has ever been designated
• Petition grounds: n/a
• Institution decision: n/a
• Final Written Decision: n/a — no claim has ever been construed, cancelled, or confirmed by the Board
• Settlement / termination: n/a
• Appeal: no FWD exists to appeal; I found no Federal Circuit appeal, Director Review request, or CourtListener docket keyed to this patent
• Defensive value: You would be the first petitioner on this patent. That cuts both ways — the upside is that no claim has been cancelled (you must build your own invalidity case from scratch), and the downside for the patent owner is that it has never had to defend these claims against a competent art-based challenge.

Verification links: USPTO PTAB E2E search — https://ptacts.uspto.gov/ptabweb/#/dashboard ; PTAB Decisions — https://www.uspto.gov/patents/ptab/decisions ; CourtListener — https://www.courtlistener.com/?q=[11320254](/patent/11320254) ; the patent itself — https://patents.google.com/patent/US11320254/en

Disambiguation note (read this before relying on any "254" hit)

Searches for 11320254 return several unrelated items that share the digits. None of the following is US 11,320,254, and none is a PTAB proceeding against it:

• PGR2025-00035, Azurity Pharmaceuticals v. Heron Therapeutics — challenges U.S. 12,115,254 (a lipid-emulsion aprepitant formulation), not 11,320,254. Different patent, different technology, different parties.
• UK company no. 11320254 (Harrandbass Ltd) — a corporate registration, per the London Gazette.
• A Travis County, TX payroll line item bearing the number 11320254.
• Various IPRs citing "the '254 patent" in briefs (Samsung/SEVEN, Heron v. Fresity/Fresenius references to 12,115,254).

I flag these explicitly because a keyword hit on "254" is the single most likely way a defendant could be misled into thinking this patent was attacked when it was not.

Family context worth knowing (not PTAB)

Adige's low-coherence interferometry portfolio shows activity abroad rather than at the Board. European counterpart granted and Spanish national translation published:

• EP 3 832 251 B1 — the European family member of this Italian priority (IT 102019000023202, filed 2019-12-06), whose description expressly recites the sub-Nyquist / sub-sampling concept and cites P. de Groot et al., "Three-dimensional imaging by sub-Nyquist sampling of white-light interferograms," Optics Letters, vol. 18, no. 17, 1993, pp. 1462–1464. National translation: ES 2 958 405 T3, published 2024-02-08.
• EP 4 070 038 B1 (granted 2024-10-30; ES 2 994 573 T3, 2025-01-27) — the sibling "determining and controlling the separation distance" case (IT filing 2020-12-07).
• EP 4 070 036 B1 (granted 2025-08-20) and US 12,214,441 (issued 2026-02-04) — the sibling "local position of at least one optical element" case.

I note these only to avoid conflating EPO opposition/validation activity with AIA trials. I found no evidence of any EPO opposition either, and in any event EPO oppositions are not PTAB proceedings and are outside the scope of this report.

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Strategic summary

Claim status: 100% UNTESTED. Not one claim of US 11,320,254 has been cancelled, confirmed, or even construed by the Board. Per the specification (the granted claims were not in the supplied text — see the summary section's caveat), the independent claims appear to be: a method claim for standoff determination, a system claim, a machine-tool claim, and a laser-processing-machine claim, with the asserted point of novelty being that the angle of incidence is controlled so the fringe spatial frequency exceeds the photodetector spatial frequency (intentional sub-sampling / aliasing; preferably k_f/k_p ≈ 1.5, 2.5, 3.5, 4.5). Because there is no Board record, there is no authoritative claim-level holding anywhere — everything about scope remains a district-court question. You should obtain the granted claims from Patent Center before drafting anything.

Estoppel landscape: effectively blank slate. Because no IPR/PGR was ever instituted, § 315(e)(2) estoppel does not apply to anyone — no petitioner, no privy, no real party in interest is barred from raising any § 102/§ 103 ground. Correspondingly, there is no petitioner-side "reasonably could have raised" trap to worry about. Conversely, if you file and lose, you inherit that estoppel yourself, and given the untested state of the claims you would be the one creating the Board's first claim-construction record — which the patent owner could then use against you in the parallel district court case. That is the principal strategic cost of being the first mover. Note also that Adige's own prosecution history contains a material prior-art citation: the de Groot Optics Letters sub-Nyquist paper appears in the family record, so an obviousness theory built on de Groot is a "previously presented art" theory that will draw an Advanced Bionics / § 325(d) discretionary-denial fight — you should be prepared with evidence of the Examiner's material error, not merely an assertion that the art is on the face of the patent.

Pattern signals. No petitioner has filed anything against this patent — no repeat-petitioner pattern exists, and there is no sign that a defensive aggregator (Unified Patents or similar) has taken an interest. Adige S.p.A. (BLM Group, Levico Terme, Italy) is an operating machine-tool manufacturer with ~51 IP assets, not a patent-assertion entity, and I found no assertion campaigns or suits by Adige that would normally trigger a defensive IPR wave. The absence of IPRs is therefore consistent with the patent simply never having been asserted, rather than with it having been tested and survived.

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Recommended next steps

If you are a defendant facing assertion of US 11,320,254 for the first time:

1. Do not rely on any prior Board ruling — there is none. There is no FWD to link to, no panel reasoning to quote, and no cancelled claim to point at. Any representation that "claims 1–5 are cancelled" or that "the patent survived an IPR" would be false for this patent. Verify claim status directly on USPTO Patent Center (application 17/110,419) and against the printed claims at https://patents.google.com/patent/US11320254/en.
2. Read the priority/§ 102 window carefully. Priority is 2019-12-06 (IT 102019000023202); the US filing is 2020-12-03. Your prior-art search must both (a) reach pre-2019-12-06 art and (b) consider whether any 2019-12-06→2020-12-03 art qualifies, and account for the possible pre-AIA/AIA boundary effects for any art in that window. The WO/PCT family (EP 4 070 038, EP 4 070 036, plus the earlier EP 3 832 251) may contain intervening publications useful as § 102(a)(2)/§ 102(e) art.
3. Attack the sub-sampling limitation head-on. The alleged novelty is the intentional aliasing condition (fringe spatial frequency > pixel spatial frequency). The family's own citation to de Groot, Optics Letters 18(17):1462–1464 (1993) on sub-Nyquist sampling of white-light interferograms, plus US 2016/059350 (optical coherence tomography standoff between a machining head and a workpiece, cited in the European record) and WO 2010/092533 (interferometric topology/shape measurement), are the natural starting references. A § 103 combination attack is likely stronger than a bare § 102 hit, because the claim element frames sub-sampling as a deliberate design choice for range extension — a motivation-to-combine story you must supply.
4. Decide IPR vs. district court deliberately. No Fintiv/§ 314(a) problem exists yet — but if litigation is already pending, the Board's current discretion practice and the parallel-art overlap will matter. Filing early maximizes the chance of institution and avoids the "already invested in the parallel case" factor; filing late forfeits the estoppel-avoidance benefit of the one-year § 315(b) bar.
5. Check for a Director Review / POP-style precedent angle. Because this would be a first-impression case on whether intentional aliasing is patentable subject matter versus an obvious design choice, be prepared for Director Review of any adverse institution or FWD.

If no litigation exists and you are merely monitoring: the correct statement is that there is no PTAB activity on US 11,320,254, and thus no defensive-artifact shortcut available. The practical implication is that anyone asserting this patent is doing so with claims that have never been tested at the Board — good news for a defendant on the merits, but also a warning that you cannot lean on someone else's invalidity work product and will have to fund your own.

Confidence and limits. I am confident in the "zero proceedings" finding: the ODP structured block says so, and four independent web searches (patent number, petitioner name, assignee/technology, and IPR-number patterns) produced no contrary evidence. I cannot rule out a very recently filed petition that ODP has not yet ingested — the ODP feed lags filings — so if you need certainty as of today, pull the docket directly from PTAB E2E (https://ptacts.uspto.gov/ptabweb/#/dashboard) and run the application number 17/110,419; that is the authoritative check, not this report.

I'll research the assignment record for US 11,320,254 through USPTO sources and related databases.

Assignment / Ownership Chain Reconstruction — US 11,320,254 B2

Sourcing note (read first): The claims/front-page material was absent from the authoritative full text supplied for this patent (truncated inside the Detailed Description), and I was unable to retrieve the USPTO Assignment Center records — specifically the reel/frame numbers and the correspondent of record — for patent 11,320,254 within my search budget. Assignment Center does not index as a crawlable static page, and my searches returned only the patent's Google Patents/Wikidata entries plus unrelated digit-collisions. What I can report authoritatively is the Google Patents "Legal Events" / reassignment block embedded in the supplied patent text, which records exactly one conveyance. I flag below precisely which fields are not evidenced so nothing is fabricated.

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Inventors

Unusual-pattern check — no flags:

• No evidence that any inventor departed the original assignee within 12 months of filing. I have no employment-transition data on these individuals, so I cannot assert either way; the absence of signal here is a data gap, not a clean bill of health.
• The inventor residence spread (Rodigo / Milan / Renate) and the academic profile of at least one co-inventor are consistent with a university–industry collaboration (Politecnico di Milano ↔ Adige SpA), which is common in Lombard laser-processing research. Note: if Previtali is a university employee, there could have been a university-side rights obligation — but the record shows the application assigned to Adige alone, and I have no evidence of any university interest.

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Original assignee

Adige S.p.A. (also rendered "ADIGE S.P.A." in the assignment record; formerly HQ'd at Levico Terme, Trentino, Italy).

• Primary line of business: Manufacturer of tube/pipe and profile laser-cutting machines, cold saws, and related measuring systems — an operating industrial machine-tool company, not a holding/licensing vehicle.
• Corporate status: Operating. Adige is part of the BLM Group (parent BLM S.p.A., Cantù, Como, Italy), a privately held group (>500 employees) covering tube bending, end-forming, sawing, and laser cutting. Google Patents lists Adige as both original and current assignee, and the patent's status is Active with anticipated expiration 2040-12-03.
• Did they ship a product embodying the claims? Likely but not confirmed. The claims (per the specification) cover optical standoff/head-height measurement for laser processing heads. BLM/Adige Lasertube systems are marketed with head-position and part-deformation measurement functions (e.g., the "ActiveScan" family), which align with the subject matter. I could not find a product datasheet explicitly naming this patent, so I mark this as inference, not evidence.

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Assignment timeline

⚠️ Reel/frame numbers and the correspondent of record could not be retrieved from Assignment Center within my search budget. The chronological events below are taken from the Google Patents legal-events block embedded in the authoritative patent text. I will not invent reel/frame or correspondent fields.

Only one recorded conveyance exists in the record:

• Execution date: not shown in supplied text / recorded 2021-01-20 — Reel/Frame not retrieved
  • Conveyance: Assignment of Assignors' Interest (i.e., inventor → company)
  • Assignor(s): COLOMBO, Daniele; DONADELLO, Simone; PREVITALI, Barbara
  • Assignee: ADIGE S.P.A.
  • Correspondent of record: not retrieved. (This is the single most valuable field for the NPE analysis the user asked for — I could not obtain it, and I am explicitly not guessing a firm.)
  • Context: Ordinary inventor-to-employer assignment executed in connection with the patent filing; no consideration structure stated. Recorded ~7 weeks after the 2020-12-03 US filing.

All other legal events are prosecution/publication events, not ownership transfers:

• 2020-12-03 — US application 17/110,419 filed by Adige S.p.A. (assignee of record at filing; priority to IT App. 102019000023202, filed 2019-12-06).
• 2021-06-10 — Publication of US 2021/0172721 A1.
• 2022-05-03 — Patent granted as US 11,320,254 B2.
• 2040-12-03 — Anticipated expiration.

No post-issuance assignment, security agreement, license, merger, change-of-name, or release appears in the record. No second assignment exists. The chain therefore terminates at Adige S.p.A. — which is itself a meaningful finding (see Verdict).

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Timeline diagram

timeline
    title Ownership of US 11320254
    2019 : Italian priority application filed
    2020 : US application filed by Adige SpA
    2021 : Inventors assign to Adige SpA
         : US pre-grant publication
    2022 : Patent granted
    2040 : Anticipated expiration

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NPE / troll-pattern signals

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Verdict

Insufficient data (only the original assignment).

This is the literal and honest call: the record contains a single inventor-to-employer assignment (assignors Donadello, Previtali, Colombo → ADIGE S.P.A., recorded 2021-01-20), the patent remains owned by the original operating assignee, and no post-issuance transfer, litigation, or defensive-aggregator endpoint exists — so there is no assignment chain to assess for NPE behavior. That said, the substantive picture is benign rather than alarming: Adige S.p.A. is an operating machine-tool manufacturer within the privately held BLM Group (Cantù/Levico Terme, Italy), a profile antithetical to patent-assertion entities, and the complete absence of shell-entity, cascade, pre-suit, bankruptcy, privateering, or aggregator signals means zero NPE indicators are present. Two caveats on completeness: (a) the reel/frame and correspondent of record were not retrievable within my search budget, and the correspondent is precisely the field that would expose a repeat-player attorney — this should be pulled directly; and (b) I could not verify a product datasheet tying the claims to a shipped BLM/Adige Lasertube model.

Verify directly at: USPTO Patent Center / Assignment Center search for patent 11,320,254 or application 17/110,419 — https://assignmentcenter.uspto.gov/ (and the legacy index at https://assignment.uspto.gov/patent/index.html) — to capture the reel/frame and correspondent fields I could not obtain.

I'll search for the USPTO record and front-page citations for U.S. Patent No. 11,320,254.

The initial searches returned unrelated patents. Let me target the specific patent record and its citation list directly.

USPTO record retrieval: what I could and could not confirm

I attempted to pull the USPTO/Google Patents front-page record (the "(56) References Cited" section) for US 11,320,254 B2 directly. I must be explicit up front:

I was unable to retrieve the front-page "References Cited" list for US 11,320,254. The authoritative text supplied earlier in this workflow was truncated inside the Detailed Description — it contained the bibliographic header, abstract, description, and classification data, but neither the claims nor the (56) References Cited section. My searches for the specific number returned the patent's bibliographic record (Google Patents/Wikidata Q138332783, PatentLeaderboard entry) but not its citation list. Under the operating rule against fabricating missing data, I will not present a list of references as if it were the patent's own citation list.

What I can confirm about the record (matches the supplied text and search hits):

Disambiguation performed (per instructions, literal ID only): searches for 11320254 also returned non-patent uses of the same digit string that must not be conflated with this patent — a UK company registration (HARRANDBASS LTD, company no. 11320254) and a PubMed accession (PMID 11320254, Muriaux et al., PNAS 2001). Neither is this patent.

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Candidate prior art most relevant to the '254 subject matter (clearly labeled as candidates, NOT confirmed front-page citations)

Because I could not obtain the actual (56) list, the following is the most technically on-point art I could identify in this exact field. None of these is confirmed to appear on the face of US 11,320,254 — treat them as research leads to verify against Patent Center/Global Dossier.

A. Patent literature in the same field (laser-processing standoff/coherence metrology)

These appear in the citation/similar-document lists of a sibling Adige application — US 2022/0410309 A1 ("Method and system for determining the local position of at least one optical element…"), same assignee family — so they are the closest patent-family neighbors in this technical space, but they are cited against that application, not established as cited against '254:

1. US 2016/0059347 A1 — Precitec Optronik GmbH — "Machining Head for a Laser Machining Device" (pub. 2016-03-03). Highly material: machining-head optical measurement for laser processing.
2. US 2020/0198051 A1 — Precitec GmbH & Co. KG — device for determining orientation of an optical device of a coherence tomograph (pub. 2020-06-25).
3. US 2020/0406393 A1 — Precitec GmbH & Co. KG — device for determining a focus position in a laser machining system (pub. 2020-12-31).
4. US 2022/0357150 A1 — Trumpf Laser GmbH — OCT-scanned region of a workpiece surface (pub. 2022-11-10). Note: published after '254's priority date, so relevant only as § 102(a)(2)/later-art context, not as anticipatory art.
5. US 11,925,999 B2 — Trumpf Laser- und Systemtechnik GmbH (2024-03-12). Post-priority; not § 102 anticipation art.

B. Non-patent literature — the most technically on-point candidates for the sub-sampling/aliasing core

The distinguishing feature of '254 is the deliberate use of sub-sampling/aliasing (fringe spatial frequency exceeding pixel spatial frequency) to extend measurement range. The foundational published art on exactly this concept — surfaced via the reference list of Zygo's US 8,126,677 B2 — is:

1. de Groot, P. et al., "Three-dimensional imaging by sub-Nyquist sampling of white-light interferograms," Optics Letters, vol. 18, no. 17, pp. 1462–1464 (Sep. 1, 1993). This is the single most relevant NPL candidate: it addresses sub-Nyquist (sub-sampled) white-light/low-coherence interferogram acquisition — the direct antecedent of the '254 sub-sampling principle.
2. de Groot et al., "Angle-resolved three-dimensional analysis of surface films by coherence scanning interferometry," Optics Letters, vol. 32, no. 12, pp. 1638–1640 (Jun. 15, 2007).
3. Dresel et al., "Three Dimensional Sensing of Rough Surfaces by Coherence Radar," Applied Optics, 31:7919–925 (Mar. 1, 1992).

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35 U.S.C. § 102 anticipation analysis

I cannot responsibly state which claim(s) any reference anticipates, for two grounded reasons:

1. The claims of '254 were not in the material supplied, and I could not retrieve them. § 102 anticipation requires element-by-element correspondence with claim limitations; a reference "disclosing the general concept" is insufficient. Without verbatim claim text I would be inventing the comparison.
2. The patent's own (56) citation list was not obtained, so I cannot represent any of the above as "a patent citation for 11320254."

What can be said with confidence about § 102 posture, framed against the apparent independent-claim concept (from the Abstract/Summary, not verbatim claims):

• The novelty-critical limitation appears to be the intentional sub-sampling condition — fringe spatial frequency greater than photodetector spatial frequency, preferably near a half-integer multiple (k_f/k_p ≈ 1.5, 2.5, 3.5, 4.5), used affirmatively to extend measurement range. Any § 102 challenge would live or die on whether a single reference discloses that limitation, not merely low-coherence spatial-domain interferometry with a fringe-position readout.
• Reference candidate 6 (de Groot 1993, sub-Nyquist white-light interferograms) is, on its face, the most plausible § 102 reference to that specific limitation, because it expressly treats sub-Nyquist sampling of low-coherence interferograms — though whether it discloses the range-extension use in a processing-tool standoff context is unverified.
• The Precitec/Trumpf patent candidates (1–3, and post-priority 4–5) are directed to coherence-tomographic/OCT monitoring in laser machining heads — relevant to the system/machine-tool claims as prior art environment, but their § 102 impact on the sub-sampling limitation is unverified.
• Any reference published after 2019-12-06 cannot anticipate (absent § 102(a)(2) via an earlier effective filing); this excludes items 4 and 5 from anticipation consideration.

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Recommended verification steps (needed before any § 102 conclusion is relied on)

1. USPTO Patent Center for application 17/110,419 → "References Cited" / "Patent and Non-Patent Literature" tabs (the authoritative (56) list).
2. Global Dossier / Espacenet for the IT priority family (IT 102019000023202) to capture any ISR/EPO search-report citations, which often parallel the US list.
3. Pull the granted claim set (which was missing from the supplied text) so limitations can be charted element-by-element.

Bottom line: I confirmed the '254 record and correctly disambiguated the number, but I could not obtain its actual front-page citations, and I will not fabricate a § 102 anticipation table against claims I cannot see. The candidates above are the strongest verified leads in the correct field; the de Groot sub-Nyquist white-light interferometry paper is the closest NPL match to the '254 sub-sampling principle. This is consistent with the earlier-generated sections, which likewise flagged the absent claims and found no litigation.

Caveat: my searches were cut off before completing the final targeted USPTO/Global Dossier queries, so the absence of the (56) list here reflects a retrieval gap, not a finding that '254 has no cited references.

I'll research the prior art landscape for this patent before building the obviousness analysis.

Let me gather the key prior art references and check the patent's own citation record.

Let me check the patent's own citation record and a few more specific references.

Obviousness Analysis — U.S. Patent No. 11,320,254 B2 under 35 U.S.C. § 103

Analyst note on the record. I was asked to "use the results from the Prior Art section of this page." The Google Patents page for US 11,320,254 supplies bibliographic data, CPC classes, the abstract, and the description, but the claim set was not in the supplied text, and I could not retrieve the patent's own face-of-the-patent "Patent Citations" list within the search budget. Accordingly:

• The claim elements analyzed below are taken from (i) the specification's Summary/Detailed Description as supplied, and (ii) the granted EP 3 832 251 B1 claim set, which is the European member of the same priority family (Italian App. 102019000023202, 2019‑12‑06) and whose claim 3 recites the decisive sub-sampling limitation. Verify the exact granted U.S. claim language on Patent Center before relying on this.
• All references below are dated against the effective filing date of 2019‑12‑06 (the Italian priority date). References published after that date are flagged.

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1. Legal framework applied

A claim is obvious under § 103 if the differences between the claimed subject matter and the prior art are such that the subject matter as a whole would have been obvious to a person having ordinary skill in the art ("PHOSITA") at the effective filing date. The Graham factors govern: scope and content of the prior art; differences between the prior art and the claims; level of ordinary skill; and secondary considerations. Under KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), a combination of familiar elements according to known methods is obvious when it yields no more than predictable results, and a "finite number of identified, predictable solutions" gives rise to a reasonable expectation of success. A statement in the specification that a result is a direct function of a design parameter (here, that measurement range is "directly proportional to the k_f/k_p ratio") is strong evidence that the result is predictable rather than unexpected.

Level of ordinary skill (assumed): a graduate engineer or physicist with 2–5 years' experience in optical metrology and/or laser materials processing instrumentation, familiar with low-coherence interferometry/OCT and with fringe-pattern signal processing.

The claim elements to be accounted for (per the specification and the EP sibling):

Elements A–E are the conventional spatial-domain low-coherence interferometer. Only element F is arguably distinctive.

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2. The prior art

Group I — Spatial-domain low-coherence interferometry with envelope-position readout (anticipates/suggests A–E)

I‑1. US 7,289,224 B2 (Zygo Corp., "Low coherence grazing incidence interferometry for profiling and tilt sensing") — https://patents.google.com/patent/US7289224
Discloses exactly the architecture of elements A–D. Claimed aspects include:

• "an array of detector elements extending in at least one dimension"; light reflected from an illuminated object point focused "as an elongated focus extending along the first dimension of the array," with a second (reference) focus "at least partially coincident along the first dimension";
• "an optical path difference (OPD) between the light reflected from the illuminated point and the second portion of light from the source varying along the first dimension of the array by an amount greater than a coherence length";
• interference-pattern envelopes whose position yields the OPD; tilt/height determined from the envelope pattern.
  This is the spatial-domain, obliquely-superimposed, envelope-localized low-coherence interferometer of elements A–E, in one reference.

I‑2. US 6,507,405 B1 (fiber-optic low-coherence interferometer for absolute distance and tilt) — https://patents.google.com/patent/US6507405
Teaches a low-coherence-length (SLED) fiber interferometer measuring absolute distance to a workpiece at a glancing (oblique) angle, using "an ordinal series of successive interference fringes" identified by the peak amplitude/envelope of the detected fringe: "principal interference fringe … having the maximum detected peak amplitude absolute value … may be used as an absolute gross measure of distance." Supplies element D/E readout (envelope peak → distance) and the oblique measurement-beam geometry.

I‑3. US 8,934,104 B2 ("Method and arrangement for robust interferometry for detecting a feature of an object") — https://patents.google.com/patent/[US8934104B2](/patent/US8934104B2)/en
Uses short-coherence (low-coherence) spatial interferograms detected on a line-scan detector, one interferogram per object point, with the envelope maximum or centroid used to determine depth/optical path length; expressly arranges "the axis y of a cylindrical optical system … parallel to" a reference line for one-dimensional focusing of the interfering light, and evaluates by lock-in at the known spatial frequency. Supplies the linear-array + cylindrical-lens dependent limitations and the envelope-centroid alternative to peak-finding.

I‑4. US 2015/0077760 A1 — https://patentimages.storage.googleapis.com/22/55/76/5cc9ee458bf59f/US20150077760A1.pdf
Background discussion of one-shot two-beam short-coherence interferometry with spatially distributed detection on a camera chip, and of the sampling-theorem constraints encountered when many fringes are imaged. Useful as evidence of the state of the art and of the recognized desire for single-shot, spatially-resolved low-coherence measurement.

Group II — Low-coherence interferometry/OCT on a laser-processing working head (motivation + integration)

II‑1. US 8,410,392 B2 / EP 1 977 850 A1 (Precitec Optronik) — cited on the face of US 9,774,783 — https://patents.google.com/patent/[US9770783](/patent/US9770783)
"A processing head for a laser processing device … an optical coherence tomograph to measure a distance between the processing head and the workpiece by measuring an optical interference between measuring light reflected by the workpiece and measuring light not reflected by the workpiece," plus a path-length modulator and a scanning device. Directly supplies the "measurement beam through the working head, reflected off the workpiece, interferometrically read to give head-to-workpiece distance" concept in the laser-processing context.

II‑2. US 8,982,339 B2 / DE 10 2010 016 862 A1 (Precitec Optronik) — "Material-working device with in-situ measurement of the working distance." Measuring beams scan the working area through the same laser scanner and objective while gathering the working distance (spectrometer-based). Supplies the scanning/folding-mirror and shared-optical-path aspects, and the in-situ standoff feedback concept.

II‑3. US 9,774,783 B2 (Precitec Optronik, "Method for measuring the distance between a workpiece and a machining head of a laser machining apparatus") — https://patents.google.com/patent/US9770783
Object beam "directed on to the workpiece by a light source of an optical coherence tomograph in such a manner that the object beam passes through the interior and the opening [of the machining head] before being incident upon the workpiece," including pressure-fluctuation compensation by a second measuring beam — i.e., beam emerges at the nozzle/beam-output end (dependent limitation).

II‑4. US 10,422,632 B2 (Precitec, "Device and method for distance measurement for a laser processing system") — https://patentimages.storage.googleapis.com/ce/ae/84/5c82b5f67b41ee/US10422632.pdf
Collimator + deflectable transmissive element + focusing lens to place the OCT measuring beam on the workpiece; expressly addresses where on the workpiece the measuring spot should lie relative to the weld/vapour capillary — the same "ahead of / coaxial with / behind the processing region" placement decision recited in the dependent claims.

II‑5. WO 2014/138939 A1 (Queen's University at Kingston, "Methods and systems for characterizing laser machining properties by measuring keyhole dynamics using interferometry") — cited art in the same field; low-coherence interferometry applied in-process to laser machining.

II‑6. DE 10 2013 008 269 A1 (referenced in the Precitec family) — recognized method for enlarging the measurement range of an OCT measuring system by synchronously adapting the reference-arm optical path length (moving mirror/prism on a linear axis). This is the "known solution to the small-range problem" that establishes the problem the '254 patent addresses — and it is the very solution the specification criticizes as mechanically complex. It therefore supplies the motivation to find a non-mechanical way to extend range.

Group III — Intentional use of aliasing / sub-Nyquist sampling to extend measurement range (element F)

III‑1. J. E. Greivenkamp, "Sub-Nyquist Interferometry," Applied Optics 26(24), 5245–5258 (Dec. 15, 1987) — https://pubmed.ncbi.nlm.nih.gov/20523512/ ; and its patent counterpart US 4,791,584 (Greivenkamp, "Sub-Nyquist Interferometry," issued Dec. 13, 1988) — https://patents.google.com/patent/US4791584
This is the single most on-point reference for element F. It expressly:

• frames the problem as the sensor's Nyquist limit — "the maximum permissible fringe frequency in the interferogram is the Nyquist frequency of the sensor (there must be two samples per fringe). Fringes at higher spatial frequencies are aliased by the sensor";
• identifies the goal: "It is therefore the object of the present invention to provide a technique for extending the measurement range of interferometry";
• teaches that aliased fringes carry recoverable information and can be re-mapped to their correct locations in the frequency domain using prior information;
• quantifies the payoff: "measurement range improvements of more than 2 orders of magnitude";
• addresses the modulation problem for fringes near/above the sampling frequency, including the sparse-array sensor (duty cycle G = a/x_s ≈ 0.1) so that high-frequency fringes are not averaged out by the pixel active area — which is precisely the physical effect that produces the patent's "contrast v vs. k_f/k_p" curve (FIG. 7) and its local maxima near half-integer multiples.

Supporting literature in the same vein (all pre‑2019):

• T. Wu, J. D. Valera, A. J. Moore, "High-speed, sub-Nyquist interferometry," Opt. Express 19(11), 10111 (2011) — https://pubmed.ncbi.nlm.nih.gov/21643269/ (doi:10.1364/OE.19.010111) — carries the sub-Nyquist concept forward into modern array detectors.
• The sampling-theory treatment reproduced in the University of Arizona dissertation chapter (figures 1.6–1.8, moiré demonstration of aliasing): "An aliased scene can be recovered, without error, using sub-Nyquist sampling … There must be no spatial frequency content from the scene in some or all of the range from zero to the Nyquist frequency … If additional information is known about the scene spectrum, these frequencies may then be remapped to their correct locations." (Arizona repository, https://repository.arizona.edu/bitstream/handle/10150/[282474](/patent/282474)/azu_td_9806848_sip1_c.pdf). This is textbook material and therefore indicative of the knowledge of a PHOSITA.

III‑2. Note on the "moiré/optical demodulation" teaching. The use of a periodic mask (grating) interposed in the beam path, or of the pixel periodicity itself as that mask, to heterodyne a high-frequency fringe pattern down to a low-frequency difference component (k_f − k_p), is standard in the spatial-synchronous / heterodyne fringe-analysis literature (e.g., the spatial synchronous and Fourier methods described in the Arizona dissertation, ch. 4, Eqs. 4.1–4.7, which derive the beat/difference component by multiplying a carrier by a reference and low-pass filtering). The '254 specification's own explanation of "analogic demodulation at the photodetectors" is an application of exactly this known heterodyning principle.

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3. Combinations that render the claims obvious

Combination 1 (principal): US 7,289,224 (Zygo) + Greivenkamp (US 4,791,584 / 1987 paper)

Motivation. (i) Both the Zygo spatial-domain approach and the Greivenkamp technique solve the same problem: how to increase the measurable OPD range of a fixed detector array without more pixels. (ii) Greivenkamp expressly states that aliased fringes are not junk and can be used to extend range by orders of magnitude — eliminating the conventional "teaching away." (iii) The '254 specification itself states the design rationale that supplies the motivation: acquiring enough fringes to satisfy Nyquist over a wide range "requires a large number of photodetectors, which brings about an excessive acquisition of information, since only the position of the envelope … is relevant." (iv) Both are in the same field of endeavor (interferometric metrology with pixel-array detectors) and would be combined by a PHOSITA with a reasonable expectation of success, because the aliasing limit is a pure sampling phenomenon independent of whether the source is coherent (Greivenkamp) or low-coherence (Zygo/Adige) — the fringe frequency set by the beam angle α and pixel pitch is unchanged by the source's coherence length.

Reasonable expectation of success. The result (increased range, reduced contrast) is mathematically determined by the sampling/MTF relationship and hence predictable, not speculative. Indeed the '254 specification confirms the proportionality: measurement range is "directly proportional to the k_f/k_p ratio."

Combination 2: Precitec OCT-head art (US 8,410,392 / US 8,982,339 / US 9,774,783) + Zygo US 7,289,224 + Greivenkamp

Precitec supplies elements A, B (partial), and the entire machine context: a laser working head with an OCT channel measuring head-to-workpiece distance, a scanning/deflection mirror, and beam emergence at the nozzle/beam output, with feedback to the machine control. Zygo supplies the spatial-domain, array-based, envelope-position readout (C–E). Greivenkamp supplies element F and the range-extension motivation, which is the specific problem in the laser-head art (small OCT measurement range, solved there by mechanically moving the reference arm — see DE 10 2013 008 269).

Motivation. Precitec's own art states the objective — a controlled, non-contact standoff for laser cutting/drilling/welding and additive manufacturing, on metallic and non-metallic workpieces (the stated deficiency of the FIG. 1 capacitive sensor of the '254 patent). Given an OCT head with a measurement range too small for real industrial standoff excursions, a PHOSITA looking to widen the range without adding a mechanical reference-arm scanner (which Precitec's own prior art makes expensive and slow) would look to sampling-domain solutions — precisely Greivenkamp.

Combination 3: US 8,934,104 + Zygo US 7,289,224 + Greivenkamp

For the dependent claims: US 8,934,104 supplies the linear/line-scan detector + cylindrical optical system for one-dimensional focusing of the interfering light (the '254 dependent limitation of a linear photodetector array with a cylindrical focusing lens) and the alternative of using the envelope maximum or centroid as the readout coordinate — matching the '254 specification's statement that the envelope position is "the position of the peak or maximum intensity of the envelope … or the average position of the photodetectors weighted with the optical intensity."

Combination 4 (alternative, for the "controlling/feedback" dependent claims): any of the above + US 10,422,632 or US 8,982,339 for placing the measuring spot ahead of / coaxial with the process region via a deflection/scanning element, and for feeding the measured distance back to the machine axis.

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4. Dependent limitations — obvious in view of the same combinations

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5. Secondary considerations (objective indicia) — assessed

• Unexpected results: Not supported. The specification's own data (1.5 µm/pixel; ~0.3 mm range at k_f/k_p ≈ 0.3; ~1.8 mm at k_f/k_p ≈ 1.5; ~5 mm at k_f/k_p ≈ 4.5) trace a linear, predicted scaling of range with k_f/k_p and with the number of illuminated pixels. A predictable, monotonic improvement is not an unexpected result; it is the expected consequence of sub-sampling.
• Teaching away: Arguable but weak. One could contend that the art conventionally avoids aliasing (Greivenkamp: "the PSI reconstruction algorithm is unable to interpret this aliased data"). However, Greivenkamp and the sampling-theory literature affirmatively teach that aliased fringes can be used to extend range, so there is no teaching away from the claimed use — rather, the reference contradicts the "teaching away" argument.
• Long-felt need / industry praise: The underlying need (non-contact standoff on non-conductive workpieces) was already being addressed by the Precitec OCT art years earlier; the record shows a crowded, active field, which cuts toward obviousness.
• Commercial success: Not evidenced in the supplied material; any nexus would have to be established separately.

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6. Weaknesses of the obviousness theory / points a patent owner would raise

1. Different interferometric regimes. Greivenkamp (US 4,791,584 / the 1987 paper) is coherent monochromatic phase-shifting interferometry used to reconstruct an aspheric wavefront via wavefront-slope-continuity a priori information and phase unwrapping — not low-coherence, spatially-detected, envelope-position metrology of a standoff distance. A patent owner will argue that one of ordinary skill would not have looked to a coherent-PSI wavefront-testing technique to solve a low-coherence envelope-tracking range problem, and that Greivenkamp's reconstruction relies on phase continuity rather than on the envelope position, so the "reconstruction" mechanism does not carry over.
   Response: Greivenkamp's reasoning about the sensor — the Nyquist limit of the pixel array, aliasing as a recoverable re-mapping, pixel-MTF/duty-cycle control to preserve modulation — is regime-independent physics. The '254 claims (as evidenced by the sibling EP claim 3) are directed to the sampling geometry (k_f > k_p, near half-integer), not to Greivenkamp's particular unwrapping algorithm. Under KSR, using a known sampling technique for its known range-extension purpose in an analogous metrology context is obvious.

2. Claim-text uncertainty. Because the granted U.S. claims were not in the supplied record, a limitation-by-limitation chart cannot be closed with certainty. If, e.g., the U.S. independent claim is limited to the envelope (rather than phase) and to the specific k_f/k_p half-integer with low-coherence illumination in a laser head, then the strongest attack is US 7,289,224 + Greivenkamp + Precitec (three references), because no single reference discloses the confluence.

3. Some references are in German / foreign-language families (DE 10 2010 016 862, DE 10 2013 008 269, EP 1 977 850). Confirm the corresponding U.S. counterparts (US 8,982,339; US 8,410,392; US 8,982,339) and their U.S. dates, since § 102/§ 103 date attribution differs between a foreign publication (only § 102(a)(1) as of its actual publication) and a U.S. patent/application publication (§ 102(a)(2) as of its effective filing date).

4. Do not rely on DE 10 2018 118 501 A1 (published 2020‑02‑06). Its publication postdates the '254 effective filing date of 2019‑12‑06 and, as a German application, it is not a "publication under section 122(b)." It may be relevant background (it describes an OCT distance-measurement device with enlarged measurement range using two reference stages), but as a matter of § 102 it is not a valid prior-art printing against the '254 claims unless an earlier-qualifying publication or U.S. counterpart exists. Flag for verification.

5. No litigation or PTAB record. As developed in the earlier section, I found no district-court case, IPR/PGR, or Federal Circuit appeal involving US 11,320,254 — consistent with a machine-tool manufacturer (Adige S.p.A., BLM/Adige group) rather than an assertion entity. The absence of a validity challenge means the § 103 case has not been tested adversarially; this analysis is therefore a hypothetical invalidity posture, not a record-based one.

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7. Bottom line

• No single reference anticipates all elements. The closest architectural reference is US 7,289,224 (Zygo), which discloses the spatial-domain low-coherence interferometer with OPD varying along the detector array beyond a coherence length and envelope-based readout — but it does not disclose deliberate sub-sampling (k_f > k_p) to extend range.
• The most persuasive § 103 combination is three references:
  US 7,289,224 (Zygo) + Greivenkamp US 4,791,584 / Applied Optics 26, 5245 (1987) + the Precitec OCT-head family (US 8,410,392; US 8,982,339; US 9,774,783; US 10,422,632).
  Zygo = the spatial-domain, low-coherence, envelope-metrology hardware; Greivenkamp = the deliberate use of aliasing/sub-Nyquist sampling to extend the measurement range (with the pixel-MTF/duty-cycle and half-integer contrast rationale that supports the "preferably ≈1.5" limitation); Precitec = the laser-working-head context, the beam-emerging-at-the-nozzle/beam-output geometry, the scanning-mirror spot placement, and the motivation (non-contact standoff feedback where capacitive sensing fails).
• Alternative two-reference combination: US 7,289,224 + Greivenkamp covers the method/system claims; the machine-tool and laser-machine claims are obvious over that pair in view of the Precitec art.
• Expect a strong obviousness case on the independent claims and the k_f/k_p half-integer dependent claim, on the theory that the range extension is a predictable, result-effective-variable optimization explicitly taught by Greivenkamp and confirmed as proportional by the '254 specification itself. The main vulnerabilities of the theory are the coherent-vs-low-coherence regime distinction and the (currently unverified) precise wording of the granted U.S. claims.

Verification checklist before reliance: (1) pull the granted U.S. claim set from USPTO Patent Center (App. 17/110,419); (2) pull the patent's face "Patent Citations" and the EP 3 832 251 search report to see which references the examiner actually considered; (3) confirm U.S. counterparts and dates for DE 10 2010 016 862, EP 1 977 850, and DE 10 2013 008 269; (4) confirm Greivenkamp's public availability as of 1987 (journal publication is sufficient).