High aperture LCD with insulating color filters overlapping bus lines on active substrate
AssigneeOIS Optical Imaging Systems, Inc.
InventorsJohn Z. Z. Zhong, Willem den Boer
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Abstract
A high aperture active matrix liquid crystal display (AMLCD) includes pixel electrodes in respective pixels which overlap adjacent address lines. The color filters are formed on the active substrate in a manner such that the filters also overlap the address lines and function as an insulating layer between the pixel electrodes and address lines in the areas of overlap. Accordingly, line-pixel capacitances are reduced and the resulting AMLCD is easier to manufacture. The total number of process step in manufacturing is reduced, and plate-to-plate (active to passive plate) alignment is much easier and less important.
Claims18
A high aperture color liquid crystal display including color filters, the display comprising:
- first and second substrates;
- a liquid crystal layer sandwiched between said first and second substrates;
- first and second different colored pixels, said first pixel including on said first substrate a first pixel electrode, a first insulating color filter, and a first thin-film transistor (TFT), and said second pixel including on said first substrate a second pixel electrode, a second insulating color filter, and a second TFT, wherein said first and second color filters are differently colored;
- said first and second pixel electrodes overlapping corresponding address lines in communication with respective TFTs so as to define a high aperture display, said overlapping forming areas of overlap;
- said first insulating color filter being at least partially disposed in an area of overlap in said first pixel between said first pixel electrode and an address line, said first color filter having a dielectric constant of less than about 5.0 and having a first contact hole defined therein that allows said first pixel electrode to be electrically connected to said first TFT;
- and
- said second insulating color filter being at least partially disposed in an area of overlap in said second pixel between said second pixel electrode and an address line, said second color filter having a dielectric constant less than about 5.0 and having a second contact hole defined therein that allows said second pixel electrode to be electrically connected to said second TFT.
A pixel having a photo-imageable color filter in a liquid crystal display, the pixel comprising:
- first and second substrates;
- a liquid crystal layer sandwiched between said first and second substrates;
- a thin film transistor (TFT) provided on said first substrate including a gate electrode, a drain electrode, and a source electrode;
- a first address line provided on said first substrate, said first address line in communication with said gate electrode;
- a second address line provided on said first substrate, said second address line in communication with said drain electrode;
- a pixel electrode provided on said first substrate, said pixel electrode overlapping at least a portion of said TFT and overlapping at least a portion of one of said address lines so as to define areas of overlap;
- a color filter insulating layer provided on said first substrate in said areas of overlap, said color filter insulating layer having a dielectric constant .di-elect cons. less than about 5.0 and a thickness of at least about 1.0 .mu.m in said areas of overlap;
- wherein said color filter includes a contact hole defined therein proximate said source electrode so that said pixel electrode electrically communicates with said source electrode through said contact hole;
- and
- wherein said color filter overlaps said address line(s) to a greater extent than does said pixel electrode.
Dependencies are inferred from the claim text.