Invalidity dossier
US 5828488
Reflective polarizer display
Current assignee: 3M Innovative Properties Co
Added 9/23/2026, 2:33:13 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
US 5,828,488 A — Reflective Polarizer Display
Title: Reflective polarizer display
Patent number: US5828488A
Application number: US08/402,349
Assignee/current assignee: Minnesota Mining and Manufacturing Co (original); 3M Innovative Properties Co (current, per the source)
Priority date: 1993-12-21
Filing date: 1995-03-10
Publication/grant date: 1998-10-27
Status: Expired – Lifetime (anticipated expiration 2015-10-27)
Purpose and plain-language scope (as the excerpt shows): The reference is directed to a display incorporating a reflective polarizer. The title and classification entries place it among layered products and polarising optical elements—specifically polarisers formed as thin sheets or foils including multiple thin layers (multilayer stacks), including organic/polymeric layers, and birefringent or phase-retarding elements. Classification also links it to liquid crystal display construction, notably structural association of cells with optical devices and reflective polarizers. On its face, the excerpt indicates a display arrangement in which a reflective polarizer is used with a liquid crystal cell. The prior-art keywords listed are "reflective polarizer," "light," "brightness enhanced," "surface material," and "structured surface," suggesting the described subject matter involves brightness enhancement and a structured surface in combination with the reflective polarizer.
Inventors: Andrew J. Ouderkirk; Olester Benson, Jr.; Sanford Cobb, Jr.; James M. Jonza; Michael F. Weber; David L. Wortman; Carl A. Stover.
Source: https://patents.google.com/patent/US5828488/en
What the excerpt does not establish: It contains no claims, abstract, or detailed description. It therefore does not establish the actual claim scope, the specific layer structures or materials, how the reflective polarizer and structured surface cooperate, or the exact relationship to a backlight or liquid crystal cell. It also does not establish the content of the later family filings listed (e.g., US6804058B1, US6888675B2, US7321464B2, US7852560B2). This overview relies solely on the supplied text.
Generated 10/1/2026, 9:52:13 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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