Invalidity dossier
US 4763984
Lighting apparatus and method
Current assignee: Energy Focus Inc
Added 9/23/2026, 4:17:38 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview: US4763984A
Title: Lighting apparatus and method
Patent number: US4763984A | Application number: US07/000,113
Inventors: George K. Awai; Michael D. Ernst
Original assignee: Individual (per Google Patents listing). Current assignee listed as Energy Focus Inc. Per the operating rules, I note only what the source states and do not research ownership transfers.
Key dates (as listed): Priority/filing date 1987-01-02; publication/grant 1988-08-16; anticipated expiration 2007-01-02. Legal status: Expired – Lifetime.
Classifications: G02B6/001 (light emitted along the lateral surface of a fibre-type light guide) and B29C48/05 (filamentary extrusion), among others.
Purpose and plain-language scope. The patent addresses lighting for decorative and safety purposes, including hazardous environments, where sealing electrical apparatus away from the environment reduces fire, explosion, or electrocution risk. Rather than a conventional optical fiber that conveys light end-to-end with negligible side loss, this apparatus uses fibers intentionally configured to emit light laterally along their length. Disclosed techniques include: larger core diameters (about 400–1000 microns versus conventional 3–100 micron cores) to support higher-order modes; a microetched or roughened core/cladding boundary (e.g., about 0.3 micron anomalies, formed by hydrofluoric acid etching of glass, abrasive roughening of plastic, or a roughened extrusion die); and internal light-scattering centers of differing refractive index, bubbles, or opaque/translucent particles distributed with density increasing away from a fiber end to equalize lateral emission. Light may be coupled into one or both ends, including a loop configuration, and the fibers may be packaged in an extrusion with a lens region and an underside reflector region containing the fibers.
What the source excerpt does not establish. The supplied text is partial (it is cut off mid-sentence) and omits the claims, the detailed description beyond the passages shown, and the drawings (FIGS. 1–7). It therefore does not establish the exact claim scope, the cited prior art, or the full fabrication details.
Source: https://patents.google.com/patent/[US4763984](/patent/US4763984)/en
Generated 10/1/2026, 9:50:59 PM
Cases on file (0)
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Litigation summary
Past and pending lawsuits — plaintiffs, defendants, jurisdictions, outcomes, and notable rulings.
Proceedings on file (0)
All PTAB activity →AIA trial proceedings (IPR / PGR / CBM) filed at the USPTO Patent Trial and Appeal Board against this patent. Sourced from the USPTO Open Data Portal and refreshed every six hours; each proceeding number deep-links to the PTAB E2E docket.
No PTAB proceedings on file. This patent has not been challenged via IPR, PGR, or CBM. The absence is itself a signal — well-asserted patents eventually attract IPRs. The LLM analysis below may surface filings the ODP feed hasn’t indexed yet.
PTAB challenges
AIA trial proceedings at the USPTO Patent Trial and Appeal Board — IPR, PGR, and CBM. Petitioners, judge panels, claim-level invalidation outcomes from Final Written Decisions, and Federal Circuit appeals. The single most important defensive datapoint after litigation history.
Assignment history
Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.
Prior art
Earlier patents, publications, and products that may anticipate or render the claims unpatentable.
Obviousness
Combinations of prior art that suggest the claimed invention would have been obvious under 35 U.S.C. § 103.
Extensions
Patent term adjustments, term extensions, continuations, divisionals, family members, and expiration dates.
Derivative works
Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.