Field sequential ferroelectric LCD having a single crystalline layer in which a plurality of circuit elements are formed

• US 5,617,229 A
• Filed: 08/25/1994
• Issued: 04/01/1997
• Est. Priority Date: 08/27/1993
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Ishii, Yutaka, Yamamoto, Yoshitaka, Shinomiya, Tokihiko, Tagawa, Akira, Koden, Mitsuhiro
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): Malinowski, Walter J.
• Application Number:
  US08/294,818
• Time in Patent Office: 950 Days
• Field of Search: 359/55, 359/56, 359/75, 359/82, 359/59, 359/53, 359/98, 359/66, 359/100
• US Class Current: 349/42
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G02F 1/133622 Colour sequential illumination
• CPC Class Codes: G02F 1/13475 in which at least one liquid crystal cell or layer is doped with a pleochroic dye, e.g. GH-LC cell G02F1/13476 takes precedence
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136277 formed on a semiconductor substrate, e.g. of silicon
• CPC Class Codes: G02F 1/141 using ferroelectric liquid crystals
• CPC Class Codes: G02F 2202/105 single crystal Si

Abstract

A liquid crystal display device includes: a first substrate having a single-crystalline silicon layer on one surface thereof; a transparent second substrate disposed opposite the first substrate, the surface of the first substrate having the single-crystalline silicon layer thereon facing the second substrate with a ferroelectric liquid crystal layer sandwiched therebetween; and a plurality of circuit elements formed in the single-crystalline silicon layer in a corresponding relationship to each of a plurality of pixel areas formed on the surface of the first substrate which faces the ferroelectric liquid crystal layer.

Claims

1. A liquid crystal display device comprising:

a first substrate having a single-crystalline silicon layer on one surface thereof;

a transparent second substrate disposed opposite the first substrate, the surface of the first substrate having the single-crystalline silicon layer thereon facing the second substrate with a ferroelectric liquid crystal layer sandwiched therebetween; and

a plurality of circuit elements formed in the single-crystalline silicon layer in a corresponding relationship to each of a plurality of pixel areas formed on the surface of the first substrate which faces the ferroelectric liquid crystal layer;

wherein the liquid crystal display device performs field sequential color display based on successive additive color mixing to obtain desired color at each pixel area.

2. The liquid crystal device recited in claim 1, wherein circuit elements for each pixel area include first and second transistors and a storage capacitor, a source or drain of the first transistor being connected to a gate of the second transistor and to the storage capacitor, and the second transistor being connected to supply a voltage to the pixel area.

3. A liquid crystal color display device that performs field sequential color display, comprising:

a color filter panel that permits high speed sequential switching of colors using a plurality of different color filters formed one on top of the other, where each color filter includes;

a first substrate having a single-crystalline silicon layer on one surface thereof; and

a transparent second substrate disposed opposite the first substrate, the surface of the first substrate having the single-crystalline silicon layer thereon facing the second substrate with a ferroelectric liquid crystal layer, including ferroelectric liquid crystal combined with a color dye, sandwiched therebetween; and

a plurality of circuit elements formed in the single-crystalline silicon layer in a corresponding relationship to each of a plurality of pixel areas formed on the surface of the first substrate which faces the ferroelectric liquid crystal layer,

and switching circuitry for selectively applying voltage to each of the color filters to sequentially generate light beams of different colors at each pixel area within one display frame time period.

4. The liquid crystal color display of claim 3, wherein the different colors include three primary colors red, green, and blue, the display frame time period is 1/30 second, and the switching circuitry displays images in each of the red, green, and blue colors at a frequency of 90 Hz so that each image is displayed in about 11 milliseconds or less.

5. A liquid crystal color display device as recited in claim 3, wherein circuit elements for each pixel area include first and second transistors and a storage capacitor, a source or drain of the first transistor being connected to a gate of the second transistor and to the storage capacitor, and the second transistor being connected to supply a voltage to the pixel area.