Patent EP0431886A2 successfully refreshed from Google Patents.
EP0431886A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Liquid crystal projection color display apparatus
Assignee: Panasonic Holdings Corp
•
Filing: 1990-12-04
•
Granted: —
•
Expires: 2010-12-04
Abstract
Abstract In a liquid crystal projection color display apparatus having three liquid crystal display devices used for red, green and blue lights, each liquid crystal display device has a liquid crystal display panel and a microlens array disposed on the light-source side or the light-source and screen sides of the liquid crystal display panel. The microlens array has a controllable refractive power by applying an electric power. An electric voltage is applied between transparent electrodes formed on both surfaces of a microlens array so that the refractive power of the microlens array can be made a value adapted to suit the corresponding one of red, green and blue lights.
Inventors
- 👤 Akira Otsuka
- 👤 Shin-Ichiro Ishihara
- 👤 Yoshito Miyatake
- 👤 Sadayoshi Hotta
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 02:45
CPC Classifications
G; G09; G09F; G09F13/00; H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3102; H04N9/3105; H04N9/3141; H04N9/315; H04N9/3152
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
152 words
A projection color display apparatus for imaging a color image comprising: Light source means for outputting three primary color lights, red, green and blue as an approximately parallel light; three liquid crystal display device means each for passing said three primary color lights thereby to form an optical image in accordance with an image signal; and projection lens means each for projecting said optical image on a screen; said three liquid crystal display device means each including a liquid crystal display panel having a plurality of pixels arranged in a matrix, a microlens array arranged on the light-source side of said liquid crystal display panel and having a plurality of microlenses formed in a matrix and a refractive power controllable by an electric field, and electric field application means for applying an electric field to said microlens array thereby to make each of said plurality of microlenses of a predetermined refractive power.
Claim 2
Dependent Claim
47 words
A projection color display apparatus as claimed in claim 1, wherein said electric field application means comprises a first and second transparent electrodes formed respectively on both surfaces of said microlens array, and voltage application means for applying a voltage between said first and second transparent electrodes.
Claim 3
Dependent Claim
180 words
A projection color display apparatus for imaging a color image comprising: Light source means for outputting three primary color lights, red, green and blue as an approximately parallel light; three liquid crystal display device means each for passing said three primary color lights thereby to form an optical image in accordance with an image signal; and projection lens means each for projecting said optical image on a screen; said three liquid crystal display device means each including a liquid crystal display panel having a plurality of pixels arranged in a matrix, a first microlens array and a second microlens array respectively disposed on the light-source side and the screen side of said liquid crystal panel and having a plurality of microlenses formed in a matrix and refractive powers controllable by an electric field, and electric field application means for applying an electric field to each of said first and second microlens arrays thereby to make each of said plurality of microlenses of a predetermined refractive power, thus being capable of outputting an approximately parallel light from said second microlens array.
Claim 4
Dependent Claim
52 words
A projection color display apparatus as claimed in claim 3, wherein said electric field application means comprises a first and second transparent electrodes formed respectively on both surfaces of each of said first and second microlens arrays, and voltage application means for applying a voltage between said first and second transparent electrodes.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.