Sony Corporation

Hiroaki Ichikawa

Kenichi Kikuchi

Yoshiharu Nakajima

Toshikazu Maekawa

Norimasa Furukawa

Kimio Hatajiri

Yoshitoshi Kida

Masumitsu Ino

Naoyuki Itakura

Satofumi Koike

Shizuo Nishihara

Tetsuro Ochi

Yasunori Sato

Katsuhide Uchino

Yuji Hayashi

Hisashi Kadota

Masayuki Iida

Hiroyoshi Tsubota

Takao Furusato

A display apparatus includes display means for displaying an image, a light source that irradiates light to the display means, and control means for controlling the quantity of light of the light source with pulse width modulation. The control means controls the quantity of light of the light source based on the ratio of the light-on period with pulse width modulation to the light-off period when the light source is turned off.

Display apparatus, quantity-of-light adjusting method for display apparatus and electronic equipment

A liquid crystal display apparatus and backlight adjustment method are provided. Backlight luminance sensorsA toD are disposed in the vicinity of four outer corners of an effective screen of an LCD panel. Each of the backlight luminance sensorsA toD detects the luminance of each of three primary colors. A backlight unit is composed of a three-primary LED array and a light diffusion unit. Transistors of the backlight luminance sensors and transistors of a pixel portion are formed on the same substrate in the same process. When a transistor is irradiated with backlight in its sufficient off region, an off current occurs due to light excitation. Since the value of the off current corresponds to the luminance of the rays of backlight that irradiates the transistor, the luminance of the backlight is detected with an output voltage into which the off current is converted. As a result, the luminance of the backlight is kept constant.

Liquid crystal display apparatus and backlight adjustment method

The disclosure includes various embodiments including, for example:

Display unit and backlight unit

The present invention is directed to a drive apparatus for a backlight unit () in which plural LED (Light Emitting Diode) elements are cascade-connected every three primary colors, which comprises a signal generating unit () for generating a signal having an arbitrary amplitude, an adjustment unit () for adjusting light emission quantities of groups of LED elements () on the basis of the signal which has been generated by the signal generating unit (), a voltage applying unit () for applying a predetermined voltage every the groups of LED elements (), light emission quantity detecting units () for detecting quantities of rays of light which have been emitted from the groups of LED elements (), calorific value detecting units () for detecting calorific values emitted from the groups of LED elements in accordance with the voltage which has been applied to the voltage applying unit (), and a control unit () for controlling the signal generating unit () on the basis of light emission quantities which have been detected by the light emission quantity detecting units () and calorific values which have been detected by the calorific value detecting units ().

Apparatus and method for driving backlight unit

The present invention prevents extension of the time period from powering on a device to convergence of chromaticity of emitted white light on a certain chromaticity, irrespective of the temperature when the device is powered on. A color liquid crystal display apparatus includes a liquid crystal display unit, a backlight employing LEDs of red, green and blue as its light source, a drive unit for driving the LEDs of each color, a temperature sensor for sensing the temperature of the LEDs, and a chromaticity sensor for sensing the chromaticity of white light emitted from the LEDs. The drive unit supplies a current to the LEDs to drive them, and implements feedback control of the amount of current for the LEDs of each color based on a value sensed by the chromaticity sensor so that the white light has a certain chromaticity. Furthermore, upon powering on the backlight, the drive unit retrieves initial current values of the LEDs of each color from a non-volatile memory, and corrects the initial current values according to a value sensed by the temperature sensor to activate the LEDs of each color with the corrected value.

Backlight device, method of driving backlight and liquid crystal display apparatus

In the present invention, during anH period excluding a blanking period (HB) constituting a line display period, pixel data pulses of RGB (B toR) are successively supplied for each color to corresponding signal lines for the color display of one pixel line. A control circuit () of select switches connected to the signal lines (-to-) supplies permission pulses (B toR) for the supply of data to signal lines when displaying one color among RGB to select switches (TMG), and turns on the select switch (TMG) of the signal line corresponding to another color to be displayed later in the same line display period during the period of this application by a precharge pulse (G orR) having a time duration shorter than the supply time of the pixel data of the other color (Tor T) to previously precharge the signal line of the other color to the predetermined potential. Due to this, sufficient precharging of a signal line, which became difficult due to an increase of a load capacitance of the signal line due to higher definition of the image display device and an increase in the speed of a drive clock thereof, can be achieved.

Image display device, image display panel, panel drive device, and method of driving image display panel

Liquid crystal display and backlight adjusting method

When a data processing circuit is formed on an insulating substrate by using TFTs, it is difficult to process a data signal having a high data rate, such as digital display data, at a high speed. In a data processing circuit formed on an insulating substrate by using TFTs, a data signal having a small voltage amplitude input in series is increased in level to a data signal having a large voltage amplitude by a level shift circuit (), the serial data signal having the large voltage amplitude is converted to parallel data signals by a serial-parallel conversion circuit (), and then, the parallel data signals are reduced in level to data signals having a small voltage amplitude by level shift circuits (A andB). Therefore, high-speed processing can be applied to digital data signals at a low power consumption.

Data processing circuit, display apparatus, and portable terminal

The screen is exempt from variation in brightness due to uneven temperature distribution. The color liquid crystal display unit has a color display panel of transmissive type and a backlight unit placed behind the color display panel. The backlight unit has a plurality of LEDs connected in series, the drive unit to drive the LEDs in correspondence with the LEDs, and the temperature sensor to detect the temperature of LEDs. The groups of LEDs are arranged in regions where the display unit has the same temperature. The drive unit controls current to be supplied to LEDs in response to temperature detected by the temperature sensor so that the LEDs retain the constant brightness even when the LEDs fluctuate in temperature.

A light source device capable of further reducing fluctuations in the intensity or the like of illumination light with a simple configuration is provided. The light source device may include a light source including a plurality of lighting sections controllable independently of one another; a drive means for driving the light source so that the lighting sections are sequentially turned on; a light-sensing device receiving light from the light source in which the lighting sections are sequentially turned on; and a control means for controlling the drive means on the basis of a light receiving signal obtained by the light-sensing device from a specific lighting section so as to control the light emission amount of each lighting section.

Light source for LCD with individually controlled sections

A display device able to select a driving capability corresponding to a plurality of resolutions, able to be driven in accordance with the purpose, and able to realize a lower power consumption, and a method of driving the same, providing a vertical drive circuit for processing for successively scanning scan lines in a row direction by scan pulses and successively selecting pixel circuits connected to the scan lines in units of rows in a VGA mode and for processing for successively scanning the scan lines for every adjacent plurality of scan lines in the row direction and successively selecting pixel circuits connected to the plurality of scan lines in units of the plurality of rows in a QVGA mode.

Display device and method of driving same

A backlight driving device for controlling driving of a backlight device for display, the backlight device generating predetermined white light by mixing light from a plurality of light emitting diodes of three or more colors, the backlight driving device including: storing device for storing an initial amount of current and a predetermined multiplication coefficient for each color; light quantity detecting device for detecting a light quantity for each color; and controlling device for adjusting an amount of current passed through the light emitting diodes of each color by feedback control on a basis of a detection output from the light quantity detecting device with an amount of current obtained by multiplying the initial amount of current by the predetermined multiplication coefficient as an initial value, whereby the predetermined white light is generated; wherein when a difference between the amount of current after the feedback control and the initial amount of current exceeds a predetermined threshold value, the controlling device updates the multiplication coefficient according to the amount of current after the feedback control.

Backlight driving device, backlight driving method, and liquid crystal display device

In the structure in which an input signal IN and a reverse-phase signal XIN thereof are externally input, an external IC is required for generating the reverse-phase signal XIN, and the number of required input signal terminals is two. A level shift circuit formed on an insulating substrate, such as a glass substrate, using transistors with large characteristic variations, for example, TFTs with high thresholds Vth, includes a complementary generator unit () driven by a first power supply (VCC) having an amplitude voltage equal to the amplitude voltage of a signal externally input from the substrate to generate complementary signals from a single-phase input signal IN. The complementary signals generated by the complementary generator unit () are level-shifted by a level shift unit (). Therefore, it is no longer necessary to externally input the reverse-phase signal XIN.

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Kanagawa, Japan

Hiroaki Ichikawa