LIQUID CRYSTAL COLOR MODULATOR FOR ELECTRONIC IMAGING SYSTEMS

• US 3,569,614 A
• Filed: 04/10/1969
• Issued: 03/09/1971
• Est. Priority Date: 04/10/1969
• Status: Expired due to Term

• Current Assignee: Thomas F. Hanlon
• Original Assignee: Thomas F. Hanlon
• Inventors: Hanlon, Thomas F.
• Application Number:
  US04/814,941
• Time in Patent Office: 698 Days
• US Class Current: 348/791
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: H04N 3/12 by switched stationary formation of lamps, photocells or light relays
• CPC Class Codes: H04N 9/12 Picture reproducers H04N9/11 takes precedence

Abstract

This invention utilizes the principle that a nematic liquid crystal, which is normally clear and transparent, is darkened upon application of a voltage thereto and can be darkened sufficiently to prevent light from passing therethrough. In a three color system, the instant color modulator blocks out two unselected colors by applying voltage to the liquid crystal behind the unselected color filters thus permitting the selected color to pass through the transparent liquid crystal behind its filter.

Claims

2. A liquid crystal color modulator according to claim 1, wherein said three different colors consist of the additive colors red, blue and green.

3. A liquid crystal color modulator according to claim 1, wherein said three different colors consist of the subtractive colors cyan, yellow and magenta.

4. A liquid crystal color modulator according to claim 1, wherein said other side of said one of said plates is positioned facing toward said source of light.

5. A liquid crystal color modulator according to claim 1, said one of said plates comprising said second plate.

6. A liquid crystal modulator for electronic imaging systems in the form of a sandwichlike structure composed of a first transparent electrode plate having on one side thereof a continuous uninterrupted electrode, a second transparent electrode plate having on one side thereof a multiplicity of closely spaced horizontal electrode stripes, said plates being positioned closely spaced from each other with the electrode bearing sides thereof facing toward each other, the space between said plates being filled with a nematic liquid crystal, light obstructing means on either of said plates positioned in the horizontal planes of the spaces between said electrode stripes, branch leads connecting a first group of said electrode stripes comprising the first, fourth, seventh etc. electrode stripes to a first common lead, branch leads connecting a second group of said electrode stripes comprising the second, fifth, eighth etc. electrode stripes to a second common lead, branch leads connecting a third group of said electrode stripes comprising the third, sixth, ninth etc. electrode stripes to a third common lead, and a lead extending from said continuous electrode, whereby when voltages are applied sequentially between said last-named lead and three different pairs of said common leads the liquid crystal in the horizontal planes of two of said three groups are sequentially darkened while leaving transparent the liquid crystal in the horizontal planes of the remaining one of said three groups.