In-plane field type liquid crystal display device with delta arrangement of three primary color pixels

• US 5,760,857 A
• Filed: 08/05/1996
• Issued: 06/02/1998
• Est. Priority Date: 08/21/1995
• Status: Expired due to Term

• Current Assignee: Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Hitachi, Ltd.
• Inventors: Yanagawa, Kazuhiko, Ohta, Masuyuki, Ashizawa, Keiichiro, Ogawa, Kazuhiro, Yanai, Masahiro
• Primary Examiner(s): Gross, Anita Pellman
• Assistant Examiner(s): Duong, Tai V.
• Application Number:
  US08/692,524
• Time in Patent Office: 666 Days
• Field of Search: 349/42, 349/109, 349/43, 349/143, 349/144, 349/145, 349/106, 349/108, 345/88, 345/92
• US Class Current: 349/43
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]

Abstract

A so-called in-plane electric field type color liquid crystal display device employs the following configuration in order to minimize smear. Groups of row-direction arrayed unit pixels are staggered one-half pitch of the unit pixels from the adjacent row-direction arrayed unit pixel groups. Three adjoining unit pixels are selected from two adjacent row-direction arrayed unit pixel groups so that they straddle these two unit pixel groups, and the three selected adjoining unit pixels are assigned three primary colors respectively.

Claims

1. A liquid crystal display device comprising opposing two substrates, at least one which is transparent, a liquid crystal layer interposed therebetween, a pixel electrode and a counter electrode formed on at least one of the two substrates in an area corresponding to each of unit pixels, scan signal lines each common to one group of row-direction arrayed unit pixels, switching devices turned on by a scan signal supplied to the associated scan signal line, video signal lines each common to one group of column-direction arrayed unit pixels and used to supply a video signal to the associated pixel electrodes;

wherein a light transmittance of the liquid crystal layer is changed by an electric field generated between pixel electrode and the counter electrode, the electric field having components almost parallel to the transparent substrate surface;

wherein the two groups of row-direction arrayed unit pixels are each staggered one half-pitch of the unit pixels from the adjacent groups;

wherein the scan signal lines and the counter signal lines are formed linear and the video signal lines extend in a zigzag and are located on one side of each group of column-direction arrayed unit pixels, each video signal line being common for one group of column-direction arrayed unit pixels; and

wherein the column-direction arrayed unit pixels connected through thin film transistors to the associated video signal line are arranged on each side of the video signal line alternately.

4. A liquid crystal display device according to claim 1, 2 or 3, wherein three adjoining unit pixels selected from the adjacent groups of row-direction arrayed unit pixels are arranged to straddle the adjacent groups and are assigned three primary colors respectively.

2. A liquid crystal display device comprising opposing two substrates, at least one which is transparent, a liquid crystal layer interposed therebetween, a pixel electrode and a counter electrode formed on at least one of the two substrates in an area corresponding to each of unit pixels, scan signal lines each common to one group of row-direction arrayed unit pixels, switching devices turned on by a scan signal supplied to the associated scan signal line, video signal lines each common to one group of column-direction arrayed unit pixels and used to supply a video signal to the associated pixel electrodes, and counter signal;

wherein a light transmittance of the liquid crystal layer is changed by an electric field generated between pixel electrode and the counter electrode, the electric field having components almost parallel to the transparent substrate surface;

wherein the two groups of row-direction arrayed unit pixels are each staggered one half-pitch of the unit pixels from the adjacent groups; and

wherein the scan signal lines are formed linear, and the video signal lines extend linearly in such a way that the column-direction arrayed unit pixels of each group are successively positioned at the center of and on one side of the video signal line alternately, each video signal line being common for one group of column-direction arrayed units pixels.

3. A color liquid crystal display device according to claim 2, wherein the unit pixels through the center of which the video signal line passes each have a counter electrode and a pixel electrode formed on both sides of the video signal line, and an electric field having components almost parallel to the transparent substrate surface is generated between the counter electrode and the pixel electrode supplied with a video signal through a thin film transistor to change a light transmittance of the liquid crystal layer.

5. A liquid crystal display device comprising:

a pair of substrates, at least one of which is transparent;

a liquid crystal layer interposed between said pair of substrates;

at least one polarizer in optical relationship with said liquid crystal layer;

scan signal lines formed in a row-direction over one substrate of said pair of substrates;

other lines formed in a row-direction over said one substrate;

video signal lines formed over said one substrate and crossed by said scan signal lines with an insulating layer therebetween, each of said video signal lines including at least first and second electrically connected portions, wherein said first portions extend in a column-direction, and said second portions are formed inside areas between outer edges of said scan signal lines away from said other lines and outer edges of said other lines away from said scan signal lines in a plan view;

a plurality of unit pixels formed by adjoining said video signal lines and said scan signal lines, said scan signal lines each common to one group of row-direction arrayed unit pixels of said plurality of unit pixels, and said video signal lines each common to one group of column-direction arrayed unit pixels of said plurality of unit pixels, wherein the groups of row-direction arrayed unit pixels are each staggered one-half pitch of the unit pixels from the adjacent groups; and

each of said plurality of unit pixels comprises a switching element connected to one of said video signal lines, at least a pixel electrode connected to said switching element, at least a counter electrode formed over said one substrate so that a light transmittance of said liquid crystal display device is changed by an electric field generated between said pixel electrode and said counter electrode, said electric field having a component substantially parallel to a surface of said liquid crystal layer.

6. A liquid crystal display device comprising:

a pair of substrates, at least one of which is transparent;

a liquid crystal layer interposed between said pair of substrates;

at least one polarizer in optical relationship with said liquid crystal layer;

scan signal lines formed in a row-direction over one substrate of said pair of substrates;

counter signal lines formed in a row-direction over said one substrate;

video signal lines formed over said one substrate and crossed by said scan signal lines with an insulating layer therebetween, each of said video signal lines including at least first and second electrically connected portions, wherein said first portions extend in a column-direction, and said second portions-are formed inside areas between outer edges of said scan signal lines away from said counter signal lines and outer edges of said counter signal lines away from said scan signal lines in a plan view;

a plurality of unit pixels formed by adjoining said video signal lines and said scan signal lines, said scan signal lines each common to one group of row-direction arrayed unit pixels of said plurality of unit pixels, said counter signal lines each common to one group of row-direction arrayed unit pixels of said plurality of unit pixels, and said video signal lines each common to one group of column-direction arrayed unit pixels of said plurality of unit pixels;

wherein the groups of row-direction arrayed unit pixels are each staggered one-half pitch of the unit pixels from the adjacent groups; and

each of said plurality of unit pixels comprises a switching element connected to one of said video signal lines, at least a pixel electrode connected to said switching element, at least a counter electrode connected to one of said counter signal lines so that a light transmittance of said liquid crystal display device is changed by an electric field generated between said pixel electrode and said counter electrode, said electric field having a component substantially parallel to the surface of said liquid crystal layer.

7. A liquid crystal display device according to claim 6, wherein each of said second portions of video signal lines is separated with a space from said scan signal lines and said counter signal lines in a plan view.

8. A liquid crystal display device according to claim 6, wherein at least two counter electrodes are connected to one of said counter signal lines in each of said unit pixels, and said first portions of said video signal lines are positioned between two counter electrodes in adjoining unit pixels.

9. A liquid crystal display device according to claim 8, wherein at least said counter electrodes and said pixel electrode extend in a column-direction.

10. A liquid crystal display device according to claim 6, wherein the column-direction arrayed unit pixels are connected through thin film transistors to the associated video signal line are arranged on one side of the video signal line.

11. A liquid crystal display device according to claim 6, wherein the column-direction arrayed unit pixels are connected through thin film transistors to the associated video signal line and are arranged on each side of the video signal line alternately.

12. A liquid crystal display device according to claim 6, wherein three adjoining unit pixels selected from the adjacent groups of row-direction arrayed unit pixels are arranged to straddle the adjacent groups and are assigned three primary colors respectively.

13. A liquid crystal display device comprising:

a pair of substrates, at least one of which is transparent;

a liquid crystal layer interposed between said pair of substrates;

at least one polarizer in optical relationship with said liquid crystal layer;

scan signal lines formed in a row-direction over one substrate of said pair of substrates;

counter signal lines formed in a row-direction over said one substrate;

video signal lines formed over said one substrate and crossed by said scan signal lines with an insulating layer therebetween, and extended in a column-direction; and

a plurality of unit pixels formed by adjoining said video signal lines and said scan signal lines, said scan signal lines each common to one group of row-direction arrayed unit pixels of said plurality of unit pixels, and said video signal lines each common for one group of column direction arrayed unit pixels, wherein said column-direction arrayed unit pixels are successively positioned at the center of and on one side of one of said video signal lines alternately, and wherein the groups of row-direction arrayed unit pixels are each staggered one-half pitch of one unit pixel from the adjacent groups; and

each of said plurality of unit pixels comprises a switching element connected to one of said video signal lines, at least a pixel electrode connected to said switching element, at least a counter electrode connected to one of said counter signal lines so that a light transmittance of said liquid crystal display device is changed by an electric field generated between said pixel electrode and said counter electrode, said electric field having a component substantially parallel to the surface of said liquid crystal layer.

14. A liquid crystal display device according to claim 13, wherein the unit pixels having said one of said video signal lines passing through the center thereof each have a counter electrode and a pixel electrode formed on both sides of the video signal line and extended in a column-direction.

15. A liquid crystal display device according to claim 14, wherein at least two counter electrodes are connected to one of said counter signal lines in each of said unit pixels, and said video signal lines are positioned between two counter electrodes in adjoining unit pixels.

16. A liquid crystal display device according to claim 13 or 15, wherein three adjoining unit pixels selected from the adjacent groups of row-direction arrayed unit pixels are arranged to straddle the adjacent groups and are assigned three primary colors respectively.

17. A liquid crystal display device comprising:

a pair of substrates, at least one of which is transparent;

a liquid crystal layer interposed between said pair of substrates;

at least one polarizer in optical relationship with said liquid crystal layer;

scan signal lines formed in a row-direction over one substrate of said pair of substrates;

counter signal lines formed in a row-direction over said one substrate;

video signal lines formed over said one substrate and crossed by said scan signal lines with an insulating layer therebetween, each of said video signal lines including at least first and second electrically connected portions, wherein said first portions extend in a column-direction, and said second portions extend in a row-direction between said scan signal lines and said counter signal lines in a plan view;

a plurality of unit pixels formed by adjoining said video signal lines and said scan signal lines, said scan signal lines each common to one group of row-direction arrayed unit pixels of said plurality of unit pixels, said counter signal lines each common to one group of row-direction arrayed unit pixels of said plurality of unit pixels, and said video signal lines each common to one group of column-direction arrayed unit pixels of said plurality of unit pixels;

wherein the groups of row-direction arrayed unit pixels are each staggered one-half pitch of the unit pixels from the adjacent groups;

each of said plurality of unit pixels comprises a switching element connected to one of said video signal lines, at least a pixel electrode connected to said switching element, at least a counter electrode connected to one of said counter signal lines so that a light transmittance of said liquid crystal display device is changed by an electric field generated between said pixel electrode and said counter electrode, said electric field having a component substantially parallel to the surface of said liquid crystal layer; and

wherein each of said second portions of video signal lines is separated with a space from said scan signal lines and said counter signal lines in a plan view.

21. A liquid crystal display device according to claim 17, 18, 19 or 20, wherein three adjoining unit pixels selected from the adjacent groups of row-direction arrayed unit pixels are arranged to straddle the adjacent groups and are assigned three primary colors respectively.

18. A liquid crystal display device comprising:

a pair of substrates, at least one of which is transparent;

a liquid crystal layer interposed between said pair of substrates;

at least one polarizer in optical relationship with said liquid crystal layer;

scan signal lines formed in a row-direction over one substrate of said pair of substrates;

counter signal lines formed in a row-direction over said one substrate;

video signal lines formed over said one substrate and crossed by said scan signal lines with an insulating layer therebetween, each of said video signal lines including at least first and second electrically connected portions, wherein said first portions extend in a column-direction, and said second portions extend in a row-direction between said scan signal lines and said counter signal lines in a plan view;

a plurality of unit pixels formed by adjoining said video signal lines and said scan signal lines, said scan signal lines each common to one group of row-direction arrayed unit pixels of said plurality of unit pixels, said counter signal lines each common to one group of row-direction arrayed unit pixels of said plurality of unit pixels, and said video signal lines each common to one group of column-direction arrayed unit pixels of said plurality of unit pixels;

wherein the groups of row-direction arrayed unit pixels are each staggered one-half pitch of the unit pixels from the adjacent groups;

each of said plurality of unit pixels comprises a switching element connected to one of said video signal lines, at least a pixel electrode connected to said switching element, at least a counter electrode connected to one of said counter signal lines so that a light transmittance of said liquid crystal display device is changed by an electric field generated between said pixel electrode and said counter electrode, said electric field having a component substantially parallel to the surface of said liquid crystal layer; and

wherein at least two counter electrodes are connected to one of said counter signal lines in each of said unit pixels, and said first portions of said video signal lines are positioned between two counter electrodes in adjoining unit pixels.

19. A liquid crystal display device according to claim 18, wherein at least said counter electrodes and said pixel electrode extend in a column-direction.

20. A liquid crystal display device comprising:

a pair of substrates, at least one of which is transparent;

a liquid crystal layer interposed between said pair of substrates;

at least one polarizer in optical relationship with said liquid crystal layer;

scan signal lines formed in a row-direction over one substrate of said pair of substrates;

counter signal lines formed in a row-direction over said one substrate;

video signal lines formed over said one substrate and crossed by said scan signal lines with an insulating layer therebetween, each of said video signal lines including at least first and second electrically connected portions, wherein said first portions extend in a column-direction, and said second portions extend in a row-direction between said scan signal lines and said counter signal lines in a plan view;

a plurality of unit pixels formed by adjoining said video signal lines and said scan signal lines, said scan signal lines each common to one group of row-direction arrayed unit pixels of said plurality of unit pixels, said counter signal lines each common to one group of row-direction arrayed unit pixels of said plurality of unit pixels, and said video signal lines each common to one group of column-direction arrayed unit pixels of said plurality of unit pixels;

wherein the groups of row-direction arrayed unit pixels are each staggered one-half pitch of the unit pixels from the adjacent groups;

each of said plurality of unit pixels comprises a switching element connected to one of said video signal lines, at least a pixel electrode connected to said switching element, at least a counter electrode connected to one of said counter signal lines so that a light transmittance of said liquid crystal display device is changed by an electric field generated between said pixel electrode and said counter electrode, said electric field having a component substantially parallel to the surface of said liquid crystal layer; and

wherein the column-direction arrayed unit pixels are connected through thin film transistors to the associated video signal line and are arranged on each side of the video signal line alternately.