Liquid crystal display apparatus having a film layer including polyaniline

• US 5,689,320 A
• Filed: 05/03/1995
• Issued: 11/18/1997
• Est. Priority Date: 04/28/1993
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Okada, Shinjiro, Miyata, Hirokatsu, Inaba, Yutaka, Shinjo, Katsuhiko, Katakura, Kazunori, Kaneko, Shuzo
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): MILLER, CHARLES LELAND
• Application Number:
  US08/433,066
• Time in Patent Office: 930 Days
• Field of Search: 359/56, 349/122, 349/184, 349/135
• US Class Current: 349/135
• CPC Class Codes: G09G 2310/0227 related to multiple interlacing, i.e. involving more fields than just one odd field and one even field
• CPC Class Codes: G09G 2310/06 Details of flat display driving waveforms
• CPC Class Codes: G09G 2310/061 for resetting or blanking
• CPC Class Codes: G09G 2310/065 Waveforms comprising zero voltage phase or pause
• CPC Class Codes: G09G 2320/0209 Crosstalk reduction, i.e. to reduce direct or indirect influences of signals directed to a certain pixel of the displayed image on other pixels of said image, inclusive of influences affecting pixels in different frames or fields or sub-images which constitute a same image, e.g. left and right images of a stereoscopic display
• CPC Class Codes: G09G 2320/0247 Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/2014 by modulation of the duration of a single pulse during which the logic level remains constant
• CPC Class Codes: G09G 3/207 by domain size control G09G3/3637 takes precedence
• CPC Class Codes: G09G 3/3637 with intermediate tones displayed by domain size control domain size control in flat matrix panels other than liquid crystal displays having memory effects G09G3/207

Abstract

A liquid crystal display device having a matrix of pixels in driven for gradational display with better temperature compensation and better flicker suppression by a driving method, wherein (a) a first voltage signal is applied to a pixel on a selected scanning line, the first voltage signal including a clear pulse, a writing pulse of a polarity opposite to that of the clear pulse and a correction pulse of a polarity opposite to that of the writing pulse, (b) a second voltage signal is applied to an associated pixel on a subsequent scanning line, the second voltage signal including a clear pulse, a writing pulse and a correction pulse of which polarities are respectively opposite to corresponding pulses of the first voltage signal, and (c) the correction pulse applied to the pixel on the selected scanning line is determined based on gradation data for the associated pixel on the subsequent scanning line, and the writing pulse applied to the pixel on the selected scanning line is determined based on gradation data for the pixel on the selected scanning line and the above-determined correction pulse.

Claims

1. A liquid crystal apparatus, comprising a liquid crystal device of the type comprising a pair of oppositely disposed electrode plates having thereon a group of scanning electrodes and a group of data electrodes, respectively, and a ferroelectric liquid crystal layer disposed between the pair of electrode plates so as to form a pixel at each intersection of the scanning electrodes and data electrodes;

and drive means including scanning signal application means and data signal application means for writing plural times in each pixel to form a domain wall separating regions of different optical states in the pixel to effect a desired gradational display,

wherein a film layer comprising polyaniline and having a volume resistivity of 10⁴ -10⁸ ohm.cm is disposed between the ferroelectric liquid crystal layer and at least one of the scanning electrodes and the data electrodes.

2. A liquid crystal apparatus comprising a liquid crystal device of the type comprising a pair of oppositely disposed electrode plates having thereon a group of scanning electrodes and a group of data electrodes, respectively, and a ferroelectric liquid crystal layer disposed between the pair of electrode plates so as to form a pixel at each intersection of the scanning electrodes and data electrodes;

and drive means including scanning signal application means and data signal application means for writing plural times in each pixel to form a domain wall separating regions of different optical states in the pixel to effect a desired gradational display,

wherein a film layer comprising polyaniline and having a volume resistivity of 10⁴ -10⁸ ohm.cm is disposed between the ferroelectric liquid crystal layer and at least one of the scanning electrodes and the data electrodes,

said film layer has a laminate structure comprising at least two layers including an organic layer disposed on a side of the liquid crystal layer for alignment control of the liquid crystal and an inorganic layer disposed on a side of the electrodes, and

said organic layer comprises polyaniline.