Active-matrix display device with added capacitance electrode wire and secondary wire connected thereto

• US 5,162,901 A
• Filed: 05/23/1990
• Issued: 11/10/1992
• Est. Priority Date: 05/26/1989
• 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: Saito, Hisashi, Tanaka, Hirohisa, Ujimasa, Hitoshi, Shimada, Yasunori
• Primary Examiner(s): Hille, Rolf
• Assistant Examiner(s): TRAN, MINH LOAN
• Application Number:
  US07/527,191
• Time in Patent Office: 902 Days
• Field of Search: 350/333, 350/334, 350/336, 340/784 C, 359/54, 359/59, 359/87, 359/88, 357/4, 357/23.7
• US Class Current: 349/39
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/13629 Multilayer wirings
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52

Abstract

An active-matrix display device having low-resistance added capacitance electrode wires in which single or plural secondary wires connected electrically to the added capacitance electrode wires reduce the apparent electrical resistance of the added capacitance electrode wires, which makes the time constant of the added capacitance electrode wires smaller, so that the charging characteristics of the added capacitance are improved and contrast and other display characteristics of the liquid crystal display device are improved.

Claims

1. An active-matrix display device comprising a pair of insulation substrates that face each other, picture element electrodes that are arranged in a matrix on an inner surface of one of said substrates, an added capacitance electrode wire made of a transparent conductive film that faces each of said picture element electrodes with at least one insulation film sandwiched therebetween, and a secondary wire that is disposed above said added capacitance electrode wire with an insulation film sandwiched therebetween, said insulation film having at least a connection groove by which said added capacitance electrode wire and said secondary wire are electrically connected to each other, an anode oxidation film being formed on said secondary wire and gate electrodes formed on said insulation film.

2. An active-matrix device according to claim 1 wherein the said gate electrodes are made of the same metal as that of the said secondary wire, and the said metal can be anodized.

3. An active-matrix display device comprising a pair of insulation substrates, a number of scanning lines that are disposed in a parallel manner on an inner surface of one of said substrates, a connection terminal that is formed at one end of each of said scanning lines, a number of added capacitance electrode wires each of which have electrical resistance and are arranged in a parallel manner between the adjacent scanning lines, said added capacitance electrode wires being made of a transparent conductive film, and a secondary wire for reducing the electric resistance of said added capacitance electrode wires,

wherein said scanning lines each of which is electrically connected to a connection terminal at its one end are disposed alternatively in the opposite direction in a parallel manner, and said secondary wire is composed of first parts that are electrically connected to said corresponding added capacitance electrode wires so as to be parallel to said scanning lines and second parts that electrically connect with said first parts of said secondary wire so that said secondary wire is positioned in a zigzag manner.

4. An active-matrix display device according to claim 3, wherein said secondary wire is positioned to be divided into plural portions.