Reflective color light filter and method of manufacture

• US 5,267,060 A
• Filed: 05/19/1992
• Issued: 11/30/1993
• Est. Priority Date: 09/28/1990
• Status: Expired due to Fees

• Current Assignee: Rockwell International Corporation
• Original Assignee: Rockwell International Corporation
• Inventors: Colton, Russell F.
• Primary Examiner(s): NOT, DEFINED
• Application Number:
  US07/887,112
• Time in Patent Office: 560 Days
• Field of Search: 350/3.7, 350/3.75, 350/3.76, 350/162.19, 350/162.2, 359/25, 359/15, 359/22, 359/589, 359/590, 359/24, 250/226
• US Class Current: 359/15
• CPC Class Codes: G02B 5/203 having holographic or diffractive elements diffraction gratings per se G02B5/18; holographic elements per se G02B5/32; generating the spectrum using diffraction elements G01J3/18
• CPC Class Codes: G02B 5/32 Holograms used as optical elements
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G03H 1/26 Processes or apparatus specially adapted to produce multiple sub- holograms or to obtain images from them, e.g. multicolour technique
• CPC Class Codes: G03H 2001/0415 for recording reflection holograms
• CPC Class Codes: G03H 2222/18 RGB trichrome light
• CPC Class Codes: G03H 2223/12 Amplitude mask, e.g. diaphragm, Louver filter
• CPC Class Codes: G03H 2250/34 Colour layer

Abstract

A color matrix display including a color matrix reflective filter (10) having groups of reflective red, green and blue (R, G, B) color elements (12) arranged in subgroups (20). The elements (12) of each color group (R, B, G) in each subgroup (20) are aligned with pixel subgroups of a matrix control element or LCD (18). The color elements (12) of the reflective filter transmit light (26) of their associated color to an aligned pixel associated with that color and reflect back (30) light of other colors to a reflective light assembly (16) for reuse. The color matrix reflective filter (10) is made by selectively exposing selected areas of a holographic optical element, or HOE, with a light of colors other than the color desired to be transmitted by that element (12) of that selected area.

Claims

1. A color filter comprising:

a holographic optic element substrate;

a planar plurality of first reflective color filter elements each having an illuminated side and an opposing viewer side, disposed on said substrate, for selectively transmitting light therethrough of a first predetermined bandwidth, from said illuminated side to said viewer side, so that, said first predetermined bandwidth can be perceived by a viewer;

said plurality of first reflective color elements reflecting all light other than said first predetermined bandwidth in a direction away from said elements on said illuminated side;

a planar plurality of second reflective color filter elements each having an illuminated side and an opposing viewer side, disposed on said substrate, for selectively transmitting light therethrough of a second predetermined bandwidth, from said illuminated side to said viewer side, so that, said second predetermined bandwidth can be perceived by a viewer;

said plurality of second reflective color filter elements reflecting all light other than said second predetermined bandwidth in a direction away from said elements on said illuminated side; and

,

said second predetermined bandwidth being different from said first predetermined bandwidth, so that, said plurality of first reflective color filter elements do not pass any light therethrough having a wavelength which is equal to a wavelength of light that is passed through said plurality of second reflective color filter elements.