Liquid-crystal colour display

Abstract: In a liquid-crystal color display having a pair of light-transmitting substrates disposed opposite each other sandwiching a liquid crystal layer between them and color selecting members (R,G,B) and a light blocking member (6) provided on one of the pair of light-transmitting substrates, light-transmitting pixel electrodes are disposed on the liquid crystal layer side of one of the light-transmitting substrates; the pixel electrodes disposed adjacent to each other correspond to different color selecting members and are formed extending into each other's display area in alternating fashion. Accordingly, display patterns formed by adjacent pixel electrodes are allowed to overlap each other, thus making it possible to increase the number of display patterns per unit display area.

Description: BACKGROUND OF THE INVENTION 1. FIELD OF THE INVENTION The present invention relates to a colour liquid crystal display. 2. DESCRIPTION OF THE PRIOR ART It is known to provide a colour liquid crystal display in which, as shown in Fig.4, display patterns are formed by portions where transparent comb electrodes 21 and 22 on the SEG (segment) side, serving as display electrodes, overlap transparent electrodes 23 and 24 on the COM (common) side, respectively. Each element of the SEG-side display electrode 21 faces a red color filter (not shown), while each element of SEG-side display electrode 22 faces a green color filter (not shown). The display patterns are independent, the comb electrodes being individually connected to different signal lines. In the above prior art colour liquid crystal display, however, as shown in Fig.5, the display area C where display patterns are defined by the SEG-side display electrode 21 is separated from the display area D where display patterns are defined by the SEG-side display electrode 22, and the display areas C and D cannot be brought in contact with each other or made to overlap. It is therefore not possible to make a plurality of display patterns overlap each other within one display area, the resulting problem being an inability to further increase the number of display patterns per unit display area. SUMMARY OF THE INVENTION It is accordingly an object of the invention to provide a colour liquid crystal display which permits a plurality of predetermined display patterns to overlap each other within one display area and thereby achieves an increase in the number of display patterns per unit display area. According to the present invention, a colour liquid crystal display comprises: a plurality of colour selection members for transmitting light of specific colours respectively and extending over an entire display region of the device; first display electrodes defining a first predetermined image pattern to be displayed in a first display area of said region, said first display electrodes arranged in correspondence with ones of the colour selection members which select a first colour; and second display electrodes defining a second predetermined image pattern to be displayed in a second display area of said region, said second display electrodes arranged in correspondence with ones of the colour selection members which select a second colour; wherein said first and second display areas overlap each other only partially in a boundary region in which portions of the first and second display electrodes are arranged so as to extend into each other's display area in an alternating fashion. According to the present invention, since the display electrodes disposed adjacent to each other are formed extending into each other's display area in alternating fashion, display patterns formed by the adjacent display electrodes are made to overlap each other within one display area. Therefore, the number of display patterns per unit display area can be increased. BRIEF DESCRIPTION OF THE DRAWINGS Fig.1 is a detail drawing of an essential portion of a colour liquid crystal display in one embodiment of the invention; Fig.2 is a diagram showing how display areas overlap each other in the embodiment; Fig.3 is a plan view showing colour filters and a mask in accordance with the embodiment; Fig.4 is a detail drawing of an essential portion of a prior art colour liquid crystal display; and Fig.5 is a drawing showing display areas in the prior art colour liquid crystal display. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Now referring to the drawings, the preferred embodiment of the invention is described below. As shown in Fig.1, in this embodiment, transparent comb electrodes 1 and 2, formed on the SEG-side and serving as display electrodes, are disposed facing a red colour filter R and a green colour filter G, respectively. The reference sign B indicates a blue colour filter. Two light-transmitting substrates, one on the SEG side and the other on the COM side, are disposed opposite each other sandwiching a liquid crystal layer (not shown) therebetween. The colour filters, red R, green G, and blue B, are disposed over one entire surface of the SEG-side light-transmitting substrate,that is the surface facing the liquid crystal layer. The SEG-side transparent comb electrodes 1 and 2 are formed on the liquid crystal layer side of the SEG-side light-transmitting substrate. The SEG-side transparent comb electrodes 1 and 2 are arranged extending into each other's area in alternating fashion. Also, the SEG-side transparent electrodes 1 and 2 share a COM-side electrode 3 disposed opposite them across the liquid crystal layer (not shown) and form two different display patterns, upper and lower, respectively driven independently of each other. In Fig.3 there is shown a mask 6 which serves as a light-blocking member formed extending between the colour filters R, G, B. In this embodiment, production of the above display patterns is achieved by applying varying voltages to the SEG-side transparent comb electrodes 1, 2 and the COM-Side electrode 3 and thereby varying the molecular alignment in the liquid crystal layer. Also, in this embodiment, overlapping portions 5 are formed where the display area defined by the SEG-side transparent electrode 1 overlaps the display area defined by the SEG-side transparent electrode 2. That is, in the colour liquid crystal display of this embodiment, since the display area A, where the red display pattern defined by the SEG-side transparent electrode 1 is formed, overlaps the display area B where the green display area defined by the SEG-side transparent electrode 2 is formed, the number of display patterns per unit display area can be increased. The invention may be embodied in other specific forms without departing from the scope thereof as defined by the claims.

Claims: A colour liquid crystal display comprising: a plurality of colour selection members (R,G,B) for transmitting light of specific colours respectively and extending over an entire display region of the device; first display electrodes (1) defining a first predetermined image pattern to be displayed in a first display area of said region, said first display electrodes arranged in correspondence with ones of the colour selection members which select a first colour; and second display electrodes (2) defining a second predetermined image pattern to be displayed in a second display area of said region, said second display electrodes arranged in correspondence with ones of the colour selection members which select a second colour; wherein said first and second display areas overlap each other only partially in a boundary region (5) in which portions of the first and second display electrodes are arranged so as to extend into each other's display area in an alternating fashion. A colour liquid crystal display according to claim 1, wherein the first and second display electrodes (1,2) each have the form of a comb, the end portions of the teeth of which are interleaved in said boundary region (5). A colour liquid crystal display according to claim 1 or claim 2, wherein the first and second display electrodes (1,2) are opposed by the same common electrode (3). A colour liquid crystal display according to any of claims 1 to 3, wherein a light-blocking member (6) is interposed between the adjacent colour selection members. A colour liquid crystal display according to any of claims 1 to 4, wherein the colour selection members are colour filters selecting three colours, red (R), green (G) and blue (B).

Inventors: AKIMOTO KAZUHIKO, FUKUTANI HIROSHI, ITO KUNIHIKO, SHIOJI MITSUAKI, AKIMOTO, KAZUHIKO, FUKUTANI, HIROSHI, ITO, KUNIHIKO, SHIOJI, MITSUAKI
Applicants: SHARP KK, SHARP KABUSHIKI KAISHA
Application year: 1991
Main classification: G02F1
IPC codes: G02F1