Invalidity dossier
US 6392727
Reduced reflectance polarized display
Current assignee: Honeywell Inc
Added 9/23/2026, 3:10:53 PM
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Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 6,392,727 B1
Title: Reduced reflectance polarized display
Patent number / application: US 6,392,727 B1; Application US09/224,591
Inventors: Brent D. Larson; Elias S. Haim
Assignee / current assignee (as listed): Honeywell Inc.; Honeywell International Inc. Original assignee: Honeywell International Inc.
Key dates: Priority date 1998-12-31; filing date 1998-12-31; publication (grant) date 2002-05-21; anticipated expiration 2018-12-31. Legal status listed as "Expired – Lifetime." (The source notes legal status is an assumption, not a legal conclusion.)
Purpose: The invention "relates to displays, and more particularly, to methods and apparatus for reducing unwanted reflections in displays." In a conventional polarized display, reflections at boundaries between the cover glass, the air gap, and the front polarizer add to the overall reflectance. Prior remedies—antireflection coatings, index-matching adhesives, and added filters—can affect liquid crystal cell-gap uniformity, complicate repairs, suffer aging and adhesive shrinkage, attenuate display output, raise cost, cause color shifts, or raise environmental concerns.
Plain-language scope: The display adds an "auxiliary polarizer" (preferably an absorbing polarizer, similar in type to the front polarizer and preferably aligned in the same direction) disposed between the front gap and the cover glass, adjacent to the cover glass in front of the display. Light transmitted through the display passes the polarizer; light reflected after passing through the polarizer is further attenuated when it intercepts the polarizer again. Reflections from interfaces between the auxiliary polarizer and front polarizer are described as reduced by around 50%. This lowers overall reflections or relaxes the reflectance requirements for antireflection coatings on the front and auxiliary polarizers. The cover glass may also carry an antireflection material on its rear surface. Components are described as conventional LCD parts; the display may be monochrome gray-scale, binary, color, or another type, and the backlight may be omitted for a reflective configuration.
Source: https://patents.google.com/patent/US6392727/en
What the excerpt does not establish: It does not provide the full claims, complete specification text (the excerpt is explicitly partial), the full list of cited prior art, prosecution history, or the omitted portions of the description; figures are referenced but not reproduced in the supplied text.
Generated 10/1/2026, 9:51:45 PM
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Litigation summary
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Assignment history
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Prior art
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Obviousness
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Derivative works
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