Hitachi, Ltd.

Kimitoshi Oogiichi

Takanori Nakayama

Kuniyuki Matsunaga

Hitoshi Komeno

Masahiko Suzuki

Masataka Natori

Hikaru Ito

Hikaru Itou

Kazuya Nakamura

Hiroshi Ookawara

A liquid crystal display device, or more particularly, an active matrix type liquid crystal display device having a pixel electrode formed in a pixel field defined on one of two transparent substrates opposed to each other with a liquid crystal layer between them. The pixel electrode is overlapped a signal line, which is formed in a portion of the one transparent substrate coincident with a black matrix, with a dielectric between them. The width of the overlap is set to a value satisfying a condition that an electric field induced between the signal line and pixel electrode will not invade into the pixel field defined with the black matrix. Owing to the structure, inhomogeneous luminance caused by a source electrode of a thin film transistor can be avoided. Moreover, inhomogeneous luminance caused by a capacitive element can be avoided.

Liquid crystal display device

A liquid crystal display device can readily achieve uniformization of the threshold voltages of individual thin film transistors in spite of its simple construction. The liquid crystal display device includes gate signal lines juxtaposed in one direction, drain signal lines juxtaposed to intersect with the gate signal lines, thin film transistors which are respectively formed in areas each surrounded by the gate signal lines and the drain signal lines and are driven by supply of scanning signals from the gate signal lines, pixel electrodes to which video signals from the drain signal lines are to be supplied via the respective thin film transistors, a first terminal for applying voltages to the respective gate signal lines via diodes, and a second terminal for applying voltages to the respective drain signal lines via diodes.

A liquid crystal display device has an insulating first substrate, a plurality of pixels, a plurality of image signal lines, a plurality of scanning signal lines, first and second common wirings disposed on the first substrate outside the display area constituted by a plurality of the pixels, a first electrostatic protection circuit disposed between the first common wiring and the scanning signal line for causing static electricity occurring in the scanning signal line, a second electrostatic protection circuit disposed between the second common wiring and the image signal line for causing static electricity occurring in the image signal line to flow through the second common wiring, a transparent second substrate opposing the surface of the first substrate on which the first and second common wirings are disposed, through a liquid crystal layer, and a conductor disposed between the first and second substrates for electrically connecting electrodes disposed on the second substrate to terminals disposed on the first substrate, wherein the first and second common wirings are electrically connected by a conductor member made of the same material as that of the conductor.

Liquid crystal display device with protection circuit for electrostatic

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Mobara, Japan

Kimitoshi Oogiichi