Invalidity dossier
US 5359691
Backlighting system with a multi-reflection light injection system and using microprisms
Current assignee: BRITEVIEW TECHNOLOGIES Inc
Added 9/23/2026, 3:45:40 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 — US 5359691 A
Title: "Backlighting system with a multi-reflection light injection system and using microprisms"
Patent number / application: US 5359691 A; application US 08/049,509.
Assignee / inventors: Original assignee Briteview Technology Inc.; current assignee listed as Briteview Technologies Inc / Briteview Technology Inc. Inventors: Chen-Yu Tai and Han Zou.
Key dates (as listed; dates are stated assumptions, not legal conclusions):
- Priority date: 1992-10-08 (priority claimed from US 07/958,238).
- Filing date: 1993-04-19.
- Publication/grant: 1994-10-25.
- Anticipated expiration: 2012-10-08. Status: Expired – Lifetime.
- Related priority filings listed: CN 94191827 A (1994-04-15), PCT/US1994/004153 (1994-04-15), JP 6080251 A (1994-04-19).
Purpose and plain-language scope (from supplied text): The patent concerns a backlighting system intended for a liquid crystal display. It combines a "multi-reflection light injection system" for getting light into a light pipe (coupling-in) with "microprisms" (described as 2-D arrangements of prisms, protrusions, indentations, or roughened surfaces) for coupling light back out of a planar, plate-like light guide toward the display. Related concepts in the text include grooves/prisms used for coupling-in, structures varying in density/size/shape/depth along the guide to give homogeneous output intensity, and possible polarization effects.
Classification: Primarily G02B6/00–G02B6/0061 (planar light guides; coupling-in and coupling-out means; microprism arrays), with G02F1/1335 (liquid-crystal constructional arrangements).
Source: https://patents.google.com/patent/US5359691/en
What the excerpt does not establish: It provides only the front-matter, classification, and abstract/keyword-level material — the omitted body means the excerpt does not establish the actual claims, their exact wording or breadth, the detailed description, embodiments, or drawings. It also does not establish the number of claims, claim dependencies, or prosecution history. No litigation, ownership-transfer, validity, or prior-art analysis is made here.
Generated 10/1/2026, 9:51:23 PM
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Litigation summary
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Proceedings on file (0)
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PTAB challenges
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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
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Obviousness
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Extensions
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Derivative works
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