US 11202016

I'll search for the specific patent and any CAFC docket activity.

Let me run additional targeted searches to confirm there is no CAFC activity and verify the USPTO record.

Let me do a final confirmation search for any litigation or PTAB activity on this exact patent number.

Based on my searches, here is the requested summary. I interpreted the patent number literally (11202016, i.e., US11202016B2 / U.S. Patent No. 11,202,016) and did not substitute similar numbers.

US Patent 11,202,016 (US11202016B2) — Summary

Title: Imaging device

Assignee / Current Assignee: Olympus Corporation (Olympus Corp) — also the original assignee (Google Patents lists assignee as "Olympus Corp"; note Google's caveat that assignee lists may be inaccurate, but this matches the record).

Inventor: Takumi Soga

Application data:

• Application No.: US17/126,381
• Filed: December 18, 2020
• Priority date: July 13, 2018 (this is a continuation of International Application No. PCT/JP2018/026462, filed July 13, 2018, published as WO2020012630A1)
• Pre-grant publication: US20210105396A1 (published April 8, 2021)
• Issue date: December 14, 2021
• Status: Active (anticipated expiration date listed as 2038-07-13, which is consistent with the priority date plus term)

Abstract (verbatim, condensed):
"An imaging device according to an embodiment includes an imaging circuit, a variable-voltage power source, a light-emitting element, a constant current-driving circuit, and a control circuit. The control circuit is configured to turn on the light-emitting element in a period during which the imaging circuit performs imaging. The control circuit is configured to turn off the light-emitting element in a period during which the imaging circuit does not perform imaging. The control circuit is configured to control voltage applied to the light-emitting element by the variable-voltage power source on the basis of voltage of an input terminal of the constant current-driving circuit when the light-emitting element is turned on. The control circuit is configured to control the variable-voltage power source and apply predetermined voltage greater than or equal to compliance voltage of the light-emitting element to the light-emitting element when the light-emitting element is turned off."

What the invention is about: The patent addresses power-loss minimization in camera/flash illumination. An LED/LD light source is driven by a constant current-driving circuit in pulsed fashion synchronized with the camera's exposure period. To minimize power wasted (heat) in the constant-current driver, the supply voltage (VDD) is regulated by feedback from the voltage drop across the driver's input terminal while the LED is on, converging VDD to near the minimum proper level (compliance voltage + driver drop). During the off (blanking) period the supply voltage is held at or raised to a level at least equal to the LED compliance voltage so that light emission can resume cleanly at the next frame. There are 5 claims: claim 1 is the sole independent claim; claims 2–5 depend from claim 1.

Plain-language overview of the claims

Independent claim 1 (apparatus): An imaging device comprising an imaging circuit, a variable-voltage power source, a light-emitting element, a constant current-driving circuit, and a control circuit, connected so that the power source feeds the light-emitting element and the light-emitting element feeds the constant current-driving circuit. The control circuit must (a) output a PWM signal to the constant current-driving circuit to turn the light-emitting element on during imaging periods; (b) stop outputting the PWM signal to turn the light-emitting element off during non-imaging periods; (c) while the element is on, adjust the driving voltage to bring it near a predetermined target power-source voltage, based on the voltage at the input terminal of the constant current-driving circuit; and (d) while the element is off, control the variable-voltage power source to apply a predetermined voltage that is ≥ the light-emitting element's compliance voltage. In short: PWM-synchronized LED flashing for a camera, with closed-loop supply-voltage trimming during the on-time and a maintained/raised voltage during the off-time.

Claim 2 (dependent): Adds a wave-detection circuit that calculates the brightness of the image captured by the imaging circuit. The control circuit decides whether to increase the LED current based on that brightness, and if it decides to increase current, it applies a voltage greater than the compliance voltage during the off-period (i.e., pre-stages a higher supply voltage so the higher drive current will work next frame).

Claim 3 (dependent): Adds a memory storing information mapping brightness to the voltage value applied by the variable-voltage power source. The control circuit identifies the appropriate voltage from the measured brightness plus that stored relationship, and applies that identified voltage during the off-period (a "learned" feed-forward adjustment).

Claim 4 (dependent): Adds a voltage clip circuit between the input terminal of the constant current-driving circuit and the input terminal of a comparator (the comparator is used in the driving-voltage control loop). The clip circuit clamps the comparator's input voltage to a predetermined voltage, protecting the comparator from overvoltage (e.g., the high voltage drop present during the off period).

Claim 5 (dependent): During the off-period, the control circuit applies — as the predetermined off-period voltage — the same voltage that was applied to the light-emitting element at the end of the immediately preceding on-period; and in the next on-period it resumes light emission using that same end-of-last-on-period voltage. This is essentially the "hold last converged VDD" behavior described in the specification.

CAFC / litigation status

My searches of CAFC 2026 docket summaries and litigation databases returned no cases, appeals, PTAB proceedings, or docket entries involving U.S. Patent 11,202,016. The only "…016 patent" hits were unrelated patents with coincidentally similar suffixes (e.g., 11,016,918; 9,415,016; 10,912,321), not this patent.

Uncertainty note: Absence of results from public web searches does not conclusively prove there is no litigation; I could not directly query the USPTO Patent Center or PACER case-management dockets in this session. If you need a definitive legal-status or litigation docket check, the authoritative sources are USPTO Patent Center (for the file wrapper/status) and PACER/CAFC (for litigation). The bibliographic details above match the Google Patents record fetched for this patent (source: https://patents.google.com/patent/[US11202016](/patent/US11202016)/en), which is consistent with the full text provided.

The initial searches returned no relevant litigation for US Patent 11202016. Let me search more specific litigation databases and case-listing sites.

Based on my searches, I found no known litigation involving US Patent No. 11,202,016 ("Imaging device," assigned to Olympus Corporation).

Summary of search results

• Searches for "11202016" patent litigation, "US 11202016" lawsuit patent, unifiedpatents litigation "11202016", "US11202016B2" litigation OR infringement OR lawsuit, and "11202016" Olympus patent case PACER returned no case listings, docket entries, complaints, CAFC decisions, or PTAB matters identifying this patent.
• The only hit referencing the number in the search results was a Google Patents citation page (JP2005116738A / EP3113578A1 family page), which merely lists US11202016B2 as a citing/document reference — not a litigation record.
• Other results (Amgen v. Sanofi, Aortic Innovations v. Edwards Lifesciences, etc.) were unrelated and involved different patent numbers.

Conclusion

Caveats

• My search coverage included general web sources, Google Patents references, and litigation-oriented databases that are publicly indexed. I could not confirm access to complete PACER, Unified Patents portal case lists, DocketNavigator, or RPX docket archives in these searches, so the absence of results should be treated as no litigation identified, not an affirmative guarantee that none exists.
• The patent remains Active (per Google Patents status), with an anticipated expiration date of 2038-07-13, and it is part of a family including WO2020012630A1, JPWO2020012630A1, and CN112313804B. A search of country-level litigation outside the U.S. was not performed.

If you want, I can run additional targeted checks (e.g., specific PACER/Unified Patents queries or a USPTO assignment/PTAB search) with more search steps available.

Proceedings overview

There are zero AIA trial proceedings (IPR/PGR/CBM) on file for US Patent 11202016 — the USPTO Open Data Portal returns no proceedings, and web searching surfaced no older or recently filed petitions against this patent. (The only Olympus-related PTAB matter that appeared — IPR2024-01220, Olympus Corp v. Optimum Imaging Technologies LLC — challenges a different patent, U.S. 10,873,685, with Olympus as petitioner, and it settled/terminated on 2025-06-05.) The bottom line for a defendant: this patent is untested at the PTAB, which is a neutral signal — no claim has been canceled, but no petitioner has yet tested the art either, so the § 103/§ 102 grounds remain fully available to a new challenger (subject to the one-year § 315(b) bar clock from service of a complaint).

No per-proceeding entries follow because there are no proceedings to report.

Strategic summary

Claim status. All five claims of US 11202016 (independent claim 1; dependent claims 2–5) remain in force and UNTESTED before the PTAB. No claim has been canceled, sustained in a Final Written Decision, or amended. The patent is active (granted 2021-12-14, anticipated expiration 2038-07-13, per the Google Patents record), so all claims are presently enforceable against an accused product.

Estoppel landscape. Because no IPR/PGR/CBM has ever been instituted, no § 315(e) estoppel attaches to anyone. A defendant sued today faces no estoppel constraints from prior PTAB activity — every § 102/§ 103 ground based on patents or printed publications is available, including art that would have been cumulative to anything a prior petitioner could have raised. The practical limitations are statutory and procedural, not estoppel-based: (1) the § 315(b) one-year bar runs from service of a complaint, so a petition should be filed within that window; and (2) the patent issued from a PCT application (PCT/JP2018/026462, filed 2018-07-13, with a 2018-07-13 priority date), so the prior-art universe is deep — the claimed LED/LD flash driving circuitry is a crowded field, as the patent's own Background (citing JP2008-305978 and JP2005-116738) concedes. PGR is not available (the nine-month post-grant window closed long ago, and the claims are not subject to a CBM review); IPR is the only AIA vehicle.

Pattern signals. There is no pattern to read here: no serial petitioner, no patent-owner PTAB defense record, and no defensive aggregator (e.g., Unified Patents) in the chain. The assignee is Olympus Corporation, a practicing camera/endoscope manufacturer that typically asserts its imaging patents defensively or in co-litigation with other camera makers (see, e.g., Olympus's 2024–2025 coordinated IPR and EDTX/NDCA litigation campaign against Optimum Imaging Technologies over the '685 patent — a different patent family). The absence of any IPR against '02016 despite the crowded LED-driver prior art may simply reflect that the patent has not been asserted aggressively against a party with incentive to file, or that disputes have been resolved in district court or by license. It is not evidence of strength.

Recommended next steps

• There are no canceled claims and no FWDs to cite, so there is no PTAB victory to lean on. If you are a defendant facing a demand letter citing claims 1–5, your invalidity case must be built from scratch — but the field is favorable: the priority date (2018-07-13) post-dates a decade of LED-flash and constant-current driver art, and the specification itself cites JP2008-305978 and JP2005-116738 (both listed as prior art on the face of the patent), which are natural lead references for a § 103 challenge to claim 1's combination of variable-voltage supply, PWM-gated constant-current drive, and on/off-period voltage control.
• No active proceedings are pending, so there are no PTAB milestones to calendar. The operative deadline is the § 315(b) one-year bar: if a complaint has been served, an IPR petition must be filed within one year of service. If no suit has been filed yet, consider a pre-suit petition only after a careful real-party-in-interest and standing analysis.
• Before filing, run a formal search of the USPTO PTAB E2E system and the PTAB API for "11202016" to confirm the ODP snapshot is current, since the structured data reflects only the most recent ingest and the search engines showed nothing newer. Confirm there is no parallel district-court case that could trigger a Fintiv-style discretionary denial under the USPTO's reinstated discretionary-denial framework.
• If no PTAB activity exists, say so plainly — as here. The absence of a challenge is itself a signal: this is a 2021-granted Olympus imaging patent with no PTAB history; if it becomes the subject of active assertion, an IPR should be expected and would be the primary lever, given the depth of the LED-driver prior art.

Bottom line: No PTAB proceeding has ever been filed against US 11202016. All five claims stand. A defendant cannot invoke any PTAB estoppel, cancellation, or adverse finding — and equally cannot claim the patent is "hardened" by prior challenges. The patent is untested, and the art landscape (including the patent's own cited references) suggests it is challengable, but no one has yet tried.

I'll research the assignment history for US Patent 11,202,016. Let me start by checking the USPTO assignment records and related sources.

Let me dig deeper into whether this patent stayed with Olympus or was transferred during the Olympus imaging-business sale to OM Digital Solutions (JIP) in 2020–2021.

I've reached the search limit for this session, so I'll now compile the ownership analysis from the verified records I have (Google Patents legal events for US11202016B2, Olympus corporate disclosures, and inventor databases) and clearly flag what could not be confirmed.

Inventors

Unusual pattern check: None. There is no indication that the inventor departed Olympus shortly after filing, and this is a single-inventor, in-house Olympus application, not a cluster of inventors leaving an assignee ahead of a portfolio sale.

Original assignee

• Entity named on the issued patent / listed as current assignee: Olympus Corporation (Google Patents "Current Assignee" and legal-status record both name Olympus Corp).
• Line of business: At the priority date (2018-07-13) Olympus was a diversified Japanese maker of cameras/imaging products, medical endoscopes, and scientific solutions. The claims concern an imaging device whose LED/LD illumination is driven in sync with an imaging circuit's exposure period — illumination-flash/driving technology usable in camera or scope products with LED light sources.
• Product embodiment: Plausible but unconfirmed for this specific patent. Olympus shipped cameras and endoscopes with LED illumination; I found no public teardown/product mapping tying this exact patent to a shipped product.
• Current status: Operating. On 2021-01-01 Olympus completed the transfer of its Imaging (camera) business to OM Digital Solutions Corporation (backed by Japan Industrial Partners/JIP) under the definitive agreement signed 2020-09-30; Olympus itself continues as a medical/scientific-solutions company (Olympus press release, 2021-01-04). Critically, I found no recorded transfer of US 11202016 to OM Digital Solutions or any other entity — Google Patents still shows Olympus Corporation as current assignee. This may mean the patent was retained by Olympus (consistent with a medical/endoscope application) or that a foreign/global transfer was never recorded against the US case; the point is unconfirmed.

Assignment timeline

I could not query the USPTO Assignment Center database directly in this session (web-search access only), so no reel/frame numbers or correspondent-of-record names are available to me. Based on the USPTO legal-event feed reproduced on Google Patents, the only assignment event recorded against this patent is the standard inventor-to-company conveyance at filing:

• Executed ~2020 (with the 2020-12-18 US filing) / noted 2020-12-18 — Reel/Frame: not available in my sources
  • Conveyance: Assignment of Assignor's Interest (Google Patents labels it "ASSIGNMENT OF ASSIGNORS INTEREST")
  • Assignor: Takumi Soga
  • Assignee: Olympus Corporation
  • Correspondent: not available in my sources — no recurrence analysis possible
  • Context: Routine inventor-to-employer assignment recorded when the US continuation (US 17/126,381) of PCT/JP2018/026462 entered the US on 2020-12-18.

No post-issuance assignments were identified. If the USPTO Assignment Center likewise shows only this one record, the plain reading is that Olympus Corporation still owns the patent — consistent with the "Active" status and Olympus-as-current-assignee listing. Because I could not open Assignment Center directly, I cannot fully exclude an unindexed later record; treat this as "no assignment found," not "no assignment exists."

Timeline diagram

timeline
    title Ownership of US 11202016
    2018 : Filed as PCT by Olympus
    2020 : US continuation filed
         : Assigned by Soga to Olympus
    2021 : Patent issued
    2026 : Still held by Olympus Corp

NPE / troll-pattern signals

1. Shell-entity transfer — not present. No transfer to an "IP / Licensing / Holdings / Ventures" LLC is recorded. The assignee is Olympus Corporation, an operating company.
2. Known asserter in the chain — not present. No Acacia, Marathon, IV, Wi-LAN, Conversant, or other listed NPE appears anywhere in the chain. The only assignee is Olympus Corporation. No litigation naming this patent was found in the prior search stage.
3. Repeat correspondent across the chain — unclear / not assessable. Correspondent-of-record data could not be retrieved from Assignment Center in this session; there is only one recorded assignment link, so no recurrence pattern can exist to flag.
4. Cascading transfers — not present. There is a single inventor→company assignment; no chained LLC transfers exist.
5. Pre-litigation transfer — not present. No infringement suit exists for this patent (see litigation summary), and the sole assignment predates issuance, not litigation.
6. Bankruptcy fire-sale — not present. Olympus Corporation has not been in Chapter 7/11; the 2021 divestiture of the camera business to OM Digital Solutions/JIP was a negotiated sale of an operating business (stock transfer of an imaging subsidiary), not a bankruptcy patent liquidation.
7. Privateering — not present / not applicable. The OM Digital Solutions transaction transferred an ongoing camera business (R&D, manufacturing, brand) to a JIP-backed operating company — the standard Olympus imaging exit — not a patent-assertion arrangement. There is no evidence this patent was part of that deal at all.
8. Defensive aggregator (anti-NPE) — not present. The chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN.

Verdict

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

The only documented assignment is the original inventor-to-employer conveyance (Takumi Soga → Olympus Corporation, noted 2020-12-18 on the Google Patents legal-event feed), and no NPE-pattern signal — shell transfer, known asserter, cascading transfers, litigation, or bankruptcy sale — is present. No reel/frame or correspondent data could be verified because the USPTO Assignment Center was not directly reachable in this session, and the one open question (whether Olympus's 2021 imaging-business divestiture to OM Digital Solutions touched this patent) could not be resolved from public sources; Google Patents continues to list Olympus Corporation as current assignee, which ordinarily means the original operating-company assignee still owns the patent.

Verify directly at: https://assignmentcenter.uspto.gov/ (search "11202016") and cross-check the legal-events feed at https://patents.google.com/patent/US11202016/en.

I'll research the prior art citations for US Patent 11,202,016. Let me start by identifying the full list of references cited on the face of the patent and their details.

I need the complete list of the 10 cited references, since the provided text was truncated at 5. Let me search for the full citation list.

The Google Patents page shows "Patent Citations (13)" but the fetched text truncated the list. Let me retrieve the complete citation list from Google Patents.

I've reached the search-step limit, so I'll complete the analysis from the authoritative patent text provided plus the results gathered. First, an important data-integrity note.

Data caveat

The authoritative fetched text for US11202016B2 includes a section headed "Citations (10)", but the list is truncated after the fifth reference (US20090295775A1's title cuts off mid-word as "Drivi…"). A Google Patents snippet I retrieved references "Patent Citations (13)," but I could not retrieve the remaining entries within the available steps. I can therefore only fully confirm the five references reproduced in the authoritative text, plus the two background references named in the specification (which are two of the same five). Any reference list in this memo should be treated as partial unless the remaining citations are pulled from USPTO/Google Patents directly. Patent number 11202016 was interpreted literally as U.S. Patent No. 11,202,016.

The five confirmed prior-art references cited on the face of US11202016B2

1. JP2005116738A

• Full citation: JP 2005-116738 A — "LED driving circuit and power saving method thereof" (LED駆動回路およびその省電力方法)
• Applicant/Assignee: 21 Aomori Sangyo Sogo Shien Center (listed in record; Google Patents shows "21 Aomori Sangyo Sogo Shien Center")
• Priority date: 2003-10-07; Publication date: 2005-04-28
• Description: An LED driving circuit with a power-saving voltage control scheme. As the '016 specification's Background describes it: the output of the operational amplifier (i.e., the gate voltage of FET 5 in its Fig. 2) is detected, and the power-source voltage VDD applied to the LED is controlled based on that detection. This is the classic "sense the driver headroom and trim the supply rail to minimize driver power loss" technique.
• Potential § 102 relevance: Qualifies as prior art under AIA § 102(a)(1) (published well before the July 13, 2018 effective filing date). It is the closest single reference to the feedback-control half of claim 1 — adjusting driving voltage toward a near-minimum proper level based on a voltage condition inside the constant-current driver while the LED is on. However, on the face of the record it is an LED driver/power-saver, not an imaging device: nothing in the confirmed information shows an imaging circuit, PWM on/off gated to imaging vs. non-imaging (blanking) periods, or the off-period behavior of holding/applying voltage ≥ compliance voltage. Anticipation of full claim 1 is doubtful; it is most relevant to the feedback limitation of claim 1 and has little to no bearing on claims 2–5 (no imaging brightness circuit, no memory, no clip circuit, no off-period hold claimed).
• Note: This is one of the two documents the '016 specification expressly acknowledges in its "Description of Related Art" (cited as "Japanese Unexamined Patent Application, First Publication No. 2005-116738").

2. JP2008305978A

• Full citation: JP 2008-305978 A — "Step-up circuit" (昇圧回路)
• Applicant/Assignee: New Japan Radio Co., Ltd.
• Priority date: 2007-06-07; Publication date: 2008-12-18
• Description: A step-up (boost) circuit. As the '016 specification's Background describes it: the difference between the gate and source voltage of FET M1 (in its Fig. 1) is detected, and the power-source voltage VDD is controlled — again, minimizing excess headroom/power loss in the pass device by closed-loop supply control.
• Potential § 102 relevance: Prior art under § 102(a)(1). Like JP2005116738A, it is highly relevant to the closed-loop voltage-trimming limitation of claim 1 (controlling VDD based on a voltage of the driver stage toward a near-optimum value during on-time). But nothing confirmed shows the imaging circuit, PWM gating synchronized to exposure/blanking, the light-emitting element driven by a constant-current stage in an imaging context, or the off-period "≥ compliance voltage" voltage application. Does not appear to anticipate claim 1 as a whole and has no apparent disclosure for claims 2–5. Also expressly acknowledged in the '016 Background (cited as "Japanese Unexamined Patent Application, First Publication No. 2008-305978").

3. JP2008224432A

• Full citation: JP 2008-224432 A — "Defect inspection apparatus and method by photoluminescence of solar cell" (太陽電池のフォトルミネッセンスによる欠陥検査装置及び方法)
• Applicant/Assignee: Japan Aerospace Exploration Agency (JAXA)
• Priority date: 2007-03-13; Publication date: 2008-09-25
• Description: An apparatus/method for inspecting solar-cell defects by photoluminescence. By its title, it is an imaging/inspection system that likely illuminates a sample and captures emitted light — i.e., it plausibly involves an imaging sensor and a light source with coordinated timing.
• Potential § 102 relevance: Prior art under § 102(a)(1). It is the reference most plausibly relevant to the imaging-device context of claim 1 (imaging circuitry coordinated with a light source). But I could not retrieve its full text, and its focus (photoluminescence defect inspection of solar cells, likely with an excitation source rather than a camera flash/illuminator) makes anticipation of claim 1's specific arrangement (variable-voltage source → LED → constant-current driver; PWM on/off tied to imaging vs. blanking; off-period voltage ≥ compliance) unverifiable and unlikely on the face of the record. No evident bearing on claims 2–5.

4. JP2009054816A

• Full citation: JP 2009-054816 A — "Light source device" (光源装置)
• Applicant/Assignee: Yokogawa Electric Corporation
• Priority date: 2007-08-28; Publication date: 2009-03-12
• Description: A light-source device. My search for its abstract returned no usable results before the step limit. Based on title alone, it concerns a light-source apparatus — plausibly involving drive/control of a light-emitting source.
• Potential § 102 relevance: Prior art under § 102(a)(1). Without the full text I cannot responsibly map it to specific claim limitations. On available information I can only say it is a general light-source device reference; nothing confirms disclosure of the imaging-synchronized PWM gating or off-period voltage control of claim 1, or the features of claims 2–5. Unverifiable for anticipation; treat as low-confidence relevance.

5. US20090295775A1

• Full citation: US 2009/0295775 A1 — "Driving circuit of light emitting device"
• Applicant/Assignee: Samsung Electro-Mechanics Co., Ltd. (inventor listed in search results: Jin Hwan Kim)
• Priority date: 2008-06-03; Publication date: 2009-12-03
• Description: Confirmed via search results: an LED driving circuit with a DC/DC converter, an LED block (parallel groups of series LEDs), a current-source circuit between the LED groups and ground, a voltage-detection unit for the DC/DC output, a minimum-voltage detection unit that finds the minimum voltage across the current sources, a single comparator, and a PWM control unit that adjusts the DC/DC converter output so the current sources have just enough (but not excessive) headroom. This is structurally the closest analog to the '016 constant-current-driver-with-supply-voltage-feedback concept: it senses the voltage at the input (top) of the constant-current sources and regulates the supply so as to avoid power loss in the current sources.
• Potential § 102 relevance: Prior art under § 102(a)(1). This is, in my assessment, the single most relevant confirmed reference to the voltage-regulation core of claim 1 — controlling the variable power source toward a near-minimum proper voltage based on voltage at the input terminal of the constant-current stage. It may also bear on the comparator/DAC-type comparison concept. However, on confirmed information it is an LED driver/backlight-style circuit: nothing in the search results shows an imaging circuit whose exposure periods gate the PWM on/off, or the specific off-period behavior of claim 1 (apply voltage ≥ compliance voltage while the light is off), or the subject matter of claims 2–5 (brightness-based current increase, memory mapping, clip circuit, hold-last-voltage resume). Anticipation of full claim 1 is doubtful; anticipation of claims 2–5 is not supported by available information.

Most relevant prior art ranking (for the claim 1 combination)

Overall § 102 conclusion (with confidence limits)

• All five confirmed references predate the effective filing date (July 13, 2018) and thus qualify as prior art under AIA 35 U.S.C. § 102(a)(1).
• Based on the information confirmed, none of the five individually appears to anticipate the full combination of claim 1 — in particular, the combination of (i) an imaging circuit whose imaging/non-imaging periods gate the PWM on/off of the light-emitting element and (ii) the distinct off-period control rule (applying predetermined voltage ≥ the element's compliance voltage while it is held off) is not shown by any single confirmed reference.
• The references split into two families of partial relevance: (a) the "supply-voltage efficiency feedback" family (US20090295775A1, JP2005116738A, JP2008305978A) → relevant to the on-period voltage-trimming limitation of claim 1, and (b) the "imaging-plus-light-source" family (JP2008224432A; possibly JP2009054816A) → potentially relevant to the imaging-synchronized context but unverified.
• For claims 2–5, no confirmed reference discloses the added features (brightness wave-detection circuit driving a current increase with pre-staged off-period voltage; brightness-to-voltage memory mapping; comparator input voltage-clip circuit; hold-last-converged-voltage resume). Claims 2–5 appear not anticipated by the confirmed references.
• Honest-limits statement: I could not retrieve full texts of the Japanese references or the complete US20090295775A1 specification, and the record's citation list was truncated (5 of 10+ references confirmed). A rigorous element-by-element § 102 map, and any conclusion about the unconfirmed references, requires the full file wrapper (USPTO Patent Center) and full texts of the Japanese documents.

Obviousness Analysis of US 11,202,016 (US11202016B2) Under 35 U.S.C. § 103

Scope note and caveats up front

The "Prior Art" section on the fetched Google Patents record lists 10 citations, but the fetched page truncates after the fifth entry (mid-way through US20090295775A1). I was able to positively identify the following five references from that list; the remaining five could not be retrieved or confirmed in this session, and I have not speculated about them:

1. JP2005116738A (JP2005-116738) — "LED driving circuit and power saving method thereof," Aomori Sangyo Sogo Shien Center, priority 2003-10-07, published 2005-04-28.
2. JP2008224432A — "Defect inspection apparatus and method by photoluminescence of solar cell," Japan Aerospace Exploration Agency, published 2008-09-25.
3. JP2008305978A (JP2008-305978) — "Step-up circuit," New Japan Radio Co., Ltd., published 2008-12-18.
4. JP2009054816A — "Light source device," Yokogawa Electric Corp., published 2009-03-12.
5. US20090295775A1 — "Driving circuit of light emitting device," Samsung Electro-Mechanics Co., Ltd., filed 2008-06-03, published 2009-12-03.

Two of these — JP2005-116738 and JP2008-305978 — are also expressly discussed in the patent's own Background section, and the specification's FIG. 7A/7B admit the general "illumination device" concept (battery → power-source circuit → LED → constant-current driving circuit, with a voltage control circuit trimming VDD to minimize driver power loss). The analysis below therefore rests primarily on these identified references, plus conventional camera-flash/imaging-illumination knowledge. Where content is uncertain, I say so.

1. Claim 1 element chart (the sole independent claim)

2. Teachings of the identified references

JP2005-116738 (JP2005116738A). Per the patent's own Background: the output of the operational amplifier, i.e., the gate voltage of the FET, is detected and the power-source voltage VDD is controlled (see FIG. 2 of that reference). This teaches a constant-current LED driver whose supply is adaptively trimmed based on a signal representative of the driver's headroom — elements 1b–1f and 1i in a general illumination context.

JP2008-305978 (JP2008305978A). Per the patent's own Background: the difference between the gate and source voltage of the FET (M1) is detected and VDD is controlled (see FIG. 1 of that reference). Same adaptive-headroom-teaching family as JP2005-116738 — a step-up/boost converter whose output tracks the minimum needed by the pass element. Again, elements 1b–1f and 1i, but no imaging context.

US20090295775A1 (Samsung). From the retrieved text: a DC/DC converter feeds plural parallel LED groups, each in series with a current source. A minimum-voltage detection unit measures the lowest voltage across the current sources (the headroom/voltage drop), and a single comparator + PWM control unit adjusts the converter output. This is a direct, detailed disclosure of supply-voltage minimization based on the voltage at the input terminal of constant-current stages to cut power loss — a strong analog of claim-1 element 1i in the LED-array/backlight art.

JP2008224432A (JAXA). A defect-inspection apparatus that images solar cells using photoluminescence — i.e., an apparatus in which illumination and image capture are combined. I could not retrieve its full text, so I cannot verify whether it teaches frame-synchronized PWM strobing of the light source. Treat as potentially relevant only for the imaging-plus-illumination context.

JP2009054816A (Yokogawa). "Light source device." Full text not retrieved; content unknown beyond title/assignee. No reliance placed on it below except as an identified reference.

3. Proposed § 103 combinations

Combination A (strongest for claim 1): JP2005-116738 or JP2008-305978 (adaptive supply) + conventional camera-LED-flash/imaging-illumination control

• JP2005-116738 / JP2008-305978 supply: variable-voltage supply (1b), LED (1c), constant-current driver (1d), controller (1e), series connection supply→LED→driver (1f), and feedback trimming of VDD based on driver voltage (1i).
• What they lack: an imaging circuit with exposure periods (1a, 1g, 1h) and the off-period behavior of 1j.
• The gap-filler: It was routine, well before the 2018 priority date, to drive a camera flash/illumination LED with a PWM/enable signal synchronized to the imager's exposure window — turning the LED on only during the imaging (exposure) period and off during the blanking period. This was the standard architecture for LED flash in camera phones, endoscopes, and machine-vision strobes. A PHOSITA combining the adaptive-supply LED driver of JP2005-116738/JP2008-305978 with a camera controller that gates LED current by exposure sync would arrive at an imaging device meeting 1a and 1g–1h.
• Element 1j — why obvious: In the adaptive-supply art, the loop converges VDD to (compliance voltage + driver drop) with minimal margin. Applied to a pulsed imaging context, a PHOSITA immediately recognizes that if VDD were allowed to sag during the blanking (off) interval, the first PWM pulses of the next frame would not reach full current until the loop re-converged — degrading the first exposed frame. The natural design choice is to hold VDD at the last converged value (≥ compliance voltage) during the off period so the LED can resume correct light output on the first pulse of the next frame. Claim 5's own wording — apply "voltage applied to the light-emitting element at the end of a turn-on period of last time" during the off period — is simply the "do not discharge the supply capacitor / freeze the DAC" behavior that any engineer would adopt to avoid re-convergence delay. The spec itself (FIG. 4, Step ST10) describes 1j as merely not changing the DAC(c) value during blanking, i.e., the absence of a control action — which strongly undercuts patentable weight for 1j.

Combination B: US20090295775A1 + imaging/flash synchronization

US20090295775A1 is arguably the closest identified reference to element 1i: it explicitly senses the voltage across the constant-current stages and uses a comparator + PWM controller to regulate the DC/DC output to the minimum needed — i.e., "near predetermined power source voltage" by headroom feedback. It lacks only the imaging/exposure synchronization (1a, 1g, 1h) and the explicit off-period rule (1j). Adding a conventional camera-exposure-synchronized PWM gate (as in Combination A) yields claim 1 for the same reasons. The comparator + latch structure in the patent (CMP + flip-flop) is also a known way to sample a short-pulse headroom measurement, and US20090295775A1 already teaches "single comparator" feedback of minimum headroom voltage.

Combination C: JP2008224432A + either adaptive-supply reference

JP2008224432A supplies the "imaging apparatus that needs controlled illumination" context. If its full text shows pulsed/strobed illumination during inspection (photoluminescence generally requires controlled excitation light and synchronized detection), it would be a natural host reference into which the power-loss-minimizing supply control of JP2005-116738/JP2008-305978/US20090295775A1 would be grafted. I flag this as contingent on content I could not verify.

4. Graham-factor analysis and motivation to combine

Scope and content of the prior art. The identified art establishes three things independently: (i) constant-current LED drive with supply voltage adaptively minimized from headroom feedback (JP2005-116738, JP2008-305978, US20090295775A1); (ii) the power-loss problem this solves — the patent's own FIG. 7A/7B admit VDD = Vreq + Vmgn + Vdrop and the goal of minimizing Vmgn; and (iii) imaging devices with illumination (JP2008224432A context; general camera-flash practice).

Differences between claim 1 and the closest art. The real differences are (a) the imaging/exposure-synchronized on/off gating (1g–1h) and (b) the off-period voltage rule (1j). Neither is a structural novelty; both are control-timing behaviors.

Motivation / reason to combine. A PHOSITA (designer of camera-module illumination drivers, of ordinary skill in LED driver and imaging-synchronization design) would be motivated to combine for three concrete reasons:

1. Power/heat: the same loss-minimization objective that drove the adaptive-supply references is more acute in battery-powered camera illumination (flash duty is short and bursts are thermally limited) — so importing headroom feedback into an imaging flash driver is an obvious improvement with predictable benefit.
2. Exposure correctness: frame-synchronized strobing requires the LED current to be accurate on the first pulse of each frame; holding VDD at the prior converged value during blanking (1j) is the standard way to guarantee first-pulse compliance — it is the "obvious thing to try" with a known, predictable result (fast resume, per claim 5 and FIG. 4 Step ST10).
3. Setpoint tracking: when drive current must rise between frames (claim 2), a PHOSITA would raise the supply before the load change — textbook feed-forward — so the "apply voltage greater than the compliance voltage in the off period" (claim 2) is a routine control adjustment, not an inventive step.

Level of ordinary skill. Moderate: familiarity with LED constant-current drivers, boost/step-up converters with feedback, camera exposure/blanking timing, and AE (auto-exposure/brightness) metering. All claimed concepts sit comfortably within that skill set.

Secondary considerations. Nothing in the record (no long-felt-need evidence, no unexpected results, no industry copying or licensing indicia) offsets the strong prima facie case. The specification's own admission that prior-art illumination devices already performed adaptive VDD control to minimize Vmgn narrows the actual contribution to the imaging-timing context and the off-period voltage hold, both of which read as design choices.

5. Dependent claims

• Claim 2 (wave-detection circuit computing image brightness; if current is to be increased, apply voltage greater than compliance during off period): Image-brightness metering to command more flash current was ubiquitous (auto-exposure/flash-control loops). Pre-raising the supply above compliance in the off period is the necessary and obvious feed-forward companion to a current-setpoint increase (Combination B's comparator feedback alone would be too slow to re-converge mid-frame). Routine.
• Claim 3 (memory storing brightness→voltage relationship; identify voltage from brightness + stored info): Look-up-table/calibration control based on a metered parameter is a standard design expedient. Routine.
• Claim 4 (voltage clip circuit between driver input and comparator input, clipping to predetermined voltage): Voltage clamp/limiter protection circuits for comparator inputs were textbook and are acknowledged in the spec as a mere "protection circuit" against overvoltage during the off period. Routine.
• Claim 5 (off-period voltage = last end-of-on-period voltage; next on-period resumes with it): As discussed, this is the "freeze/hold the converged DAC value during blanking" default behavior — the path of least resistance, expressly implemented as a no-op in FIG. 4 (Step ST10). The least weighty limitation; trivially obvious in Combination A/B.

6. Balanced view — strongest counterarguments for the patent

• If the examiner's remaining five unidentified citations (and any art the applicant distinguished) include a reference that already combined headroom-feedback supply control with imaging-synchronized PWM strobing, the case would be even stronger against the patent. Conversely, if the art contains no camera-flash/imaging-LED reference teaching supply raising or holding during blanking, the patent's advocates would argue element 1j runs against the power-saving grain of the cited adaptive-supply art (which teaches minimizing VDD at all times). That argument has limited force, however, because claim 1's off-period voltage need only be "≥ compliance voltage," which is exactly where the adaptive loops park VDD anyway, and because holding rather than discharging a converter output during a short blanking interval is the energy-neutral default.
• The strongest genuine distinction is the combination's purpose: nobody in the cited adaptive-supply art addresses frame-by-frame pulsed operation with first-pulse current accuracy. Whether that is "unobvious combination" or "obvious application of known control to a new timing context" is the crux — and under the KSR "obvious to try / predictable result" rubric, the latter characterization is the more natural one for the claims as drafted, particularly given how broadly claim 1 is written (it does not recite the comparator/latch, the clip circuit, or the brightness feedback of the dependent claims).

7. Conclusion

On the identified record, claim 1 would most likely be held obvious under § 103 as the combination of (i) an adaptive constant-current LED driver whose supply voltage is trimmed toward the minimum from the driver's input-terminal voltage — JP2005-116738, JP2008-305978, or US20090295775A1 — with (ii) conventional imaging-exposure-synchronized PWM strobing of the illumination LED, where the off-period "≥ compliance voltage" rule (1j) is the routine hold/feed-forward behavior needed for first-pulse accuracy. Dependent claims 2–5 add metering, table-lookup, comparator input protection, and DAC-value freezing, each routine in this art. The caveats: only five of the ten listed citations were identifiable in this session, and the full texts of JP2008224432A, JP2009054816A, and the Samsung publication were only partially retrieved, so a complete § 103 case would require confirming the content of the remaining citations before finalizing an invalidity position.