Hitachi Displays, Ltd.

Hitachi Device Engineering Co., Ltd.

Other

Renesas Technology Corp.

Hitachi Ulsi Systems Co., Ltd.

Hitachi, Ltd.

Masashi Nakamura

Hiroyuki Nitta

Nobuhiro Takeda

Masahiro Tanaka

Tsutomu Furuhashi

Atsuhiro Higa

Satoru Tsunekawa

Koji Shida

Takashi Takahashi

Hiroyuki Matsumoto

Hiroshi Kurihara

Nobuyuki Koganezawa

Hirobumi Koshi

Teruaki Odaka

Teruyuki Odaka

A display device includes a pixel array having a plurality of pixels, a plurality of first signal lines and a plurality of second signal lines. A first driving circuit outputs scanning signals to the plurality of first signal lines, and a second driving circuit outputs display signals to the plurality of second signal lines. Each pixel of the plurality of pixels is operated in a normally black-displaying mode, the first driving circuit repeats a first step of sequentially selecting N lines of the plurality of first signal lines and a second step of selecting Z lines of the plurality of first signal lines that are separate from the N lines, where N and Z are natural numbers, and the second driving circuit repeats outputting N times the display signals and outputting one time a blanking signal which masks an image displayed on corresponding pixels.

Display device and driving method thereof

A display device includes a plurality of gate lines, at least one data line, and a plurality of pixels connected to the plurality of gate lines and the at least one data line. The display device is configured to perform a first step of sequentially selecting N lines of the plurality of gate lines, and sequentially outputting N times display signals to the data line, and to perform a second step of selecting Z lines of the plurality of gate lines at one time, and outputting one time a blanking signal, where N and Z are natural numbers at least equal to 2. The Z lines are separate from the N lines, and the first step and the second step are repeatedly performed.

An image sensor such as the conventional CMOS image sensor, in which automatic controls including so-called automatic iris control and white balance adjustment for adjusting the sensor sensitivity, namely the charge accumulation time in each pixel, according to the brightness of the image sensing ambience are performed, involves the problem that, when the frame rate of the image sensor is slowed to save power consumption, the operation of the automatic control systems will also become slower and the image quality deteriorates. In the invented image sensor system using a CMOS image sensor, while a CMOS image sensor is operated at the full frame rate all the time, a circuit for processing image signals from the CMOS image sensor is operated at a speed close to that of full frame processing only when the power supply is turned on or when the image sensing ambience varies and switched to a lower frame processing speed when automatic controls, including iris control, have become stabilized.

Image sensor system using CMOS image sensor and image sensor apparatus using CMOS image sensor

Turning on and off of the light source illuminating an object to be imaged is judged based on brightness changes in small and large areas set up in the frame and an electric charge storage time for each pixel is set up to be equal to the turning-on-and-off period of the light source or an integral multiple thereof. The charge storage time is changed over responsive to the turning-on-and-off period of the light source or the integral multiple thereof to set up a stored light amount for each pixel stepwise and difference in the stored light amount between steps is interpolated by continuous gain control of read-out signals of pixels.

Imaging system using solid-state CMOS imaging device

A display device of the present invention prevents the deterioration of display quality even when input video data are changed. In a matrix type display device, lines of video data are inputted to the data driver circuit one after another for every horizontal scanning period of the video data. The data driver circuit alternately repeats (i) a first step for generating a display signal corresponding to each one of the lines of the video data one after another for every fixed period and outputting the display signal to the pixel array N-times (N being a natural number equal to or greater than 2) and (ii) a second step for generating a display signal which makes the luminance of the pixels lower than the luminance of the pixel in the first step for the fixed period and outputting the display signal to the pixel array M-times (M being a natural number smaller than N). The scanning driver circuit alternately repeats (i) a first selection step for selecting the plurality of pixel rows for every Y rows (Y being a natural number smaller than the N/M) sequentially from one end to another end of the pixel array along the second direction in the first step and (ii) a second selection step for selecting the plurality of pixel rows other than the pixel rows (Y&#xd7;N) selected in the first selection step for every Z rows (Z being a natural number not smaller than N/M) sequentially from one end to another end of the pixel array along the second direction in the second step. Further, the outputting of N pieces of display signals in the first step and the outputting of M pieces of display signals in the second step are performed in response to periods which are obtained by evenly dividing the N-pieces of the horizontal scanning periods which are sequentially outputted into (N+M) pieces of periods.

A data driver of a display device alternately repeats a first step of sequentially generating a display signal corresponding to each one of the lines of image data for a fixed period and outputting the display signal to a pixel array N-times and a second step of generating a display signal which makes the luminance of pixels lower than the luminance of the pixel in the first step for the fixed period and of outputting the display signal to the pixel array M-times. A scanning driver circuit alternately repeats selecting a plurality of pixel rows for every Y rows sequentially from one end to another end of the pixel array along the second direction in the first step and selecting the plurality of pixel rows other than the pixel rows (Y&#xd7;N) sequentially from one end to another end of the pixel array for every Z rows along the second direction.

A hold-type display device for eliminating blurring without damaging the display brightness of moving images. The display device includes a pixel array including a plurality of pixels, a plurality of first signal lines, a plurality of second signal lines, a first driving circuit outputting scanning signals to the plurality of first signal lines, and a second driving circuit outputting display signals to the plurality of second signal lines. The first driving circuit repeats a step for sequentially selecting the first signal lines every Y lines for every N times and a step for selecting the first signal lines every Z lines for every M times which follows the N times. The second driving circuit repeats outputting N times the display signals and outputting M times a blanking signal which masks an image displayed on corresponding pixels.

In a display device having a pixel array in which a plurality of pixels are arranged two-dimensionally along a first direction and a second direction, each of the pixels includes a pair of electrodes applying a voltage to liquid crystals, respective groups of the pixels arranged along the first direction form a plurality of pixel-rows juxtaposed along the second direction, and respective groups of the pixels arranged along the second direction form a plurality of pixel-columns juxtaposed along the first direction, the present invention repeats a first step for selecting every Y rows of the pixel-rows sequentially along the second direction N-times and applying an image signal to one of the pair of electrodes provided for each one of the pixels belonging to the each Y rows of the pixel-rows as selected, and a second step for selecting every Z rows of the pixel-rows sequentially along the second direction M-times and applying a blanking signal to the one of the pair of electrodes provided for each one of the pixels belonging to the each Z rows of the pixel-rows as selected, alternately while the Y, the N, the Z, and the M are natural numbers satisfying relationship of M&#x3c;N and Y&#x3c;N/M&#x2266;Z, and another of the pair of electrodes in each of the pixels is kept at a reference voltage; and inverts polarity of the blanking signal supplied to each one of the pixel-columns in regard to the reference voltage to that of the image signal supplied to the each one of the pixel-columns subsequently to the blanking signal, so that horizontal stripes are prevented from appearing in a image displayed by the pixel array.

A liquid crystal drive circuit, which makes it possible to display low resolution display data on a high resolution liquid crystal panel while expanding and/or centering the display data, is provided. A multiscan control signal is inputted to a latch address control circuit and a data control circuit to control latch signals and the display data so as to latch single pixel data into a plurality of latches at the same time. The display data are latched with the expanding and/or centering operation, and outputted in synchronization with a line clock after being converted to gray scale voltages. Accordingly, it is possible to realize the lateral expansion and/or the centering operation. Further, it is also possible to realize a longitudinal expansion by adding a latch circuit between a latch circuit and a liquid crystal applied voltage generation circuit, and by outputting the data in synchronization with an expanded line clock.

Liquid crystal drive circuit and liquid crystal display apparatus

In a data transfer circuit, a hold signal generating circuit generates and outputs a hold signal Hold when transmission data is equal to transmission data one cycle before, and sets a 3-state output buffer for transmission data to high-impedance state, while, in a data reception circuit, when the hold signal Hold is valid, a data reception circuit outputs the reception data held, thereby power consumption in a data bus which is terminated with a terminal resistor is reduced.

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Chosei, Japan

Masashi Nakamura