Sony Corporation

Saturn Licensing LLC

Kimio Hatajiri

Hiroaki Ichikawa

Kenichi Kikuchi

Katuhiko Nishikawa

Yoshinori Onoe

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

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

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 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

A general scanning-period converting device is equipped with two frame memories (first and second frames), and a video signal is written in any one of the frame memories (e.g., first memory) at a scanning period thereof while the video signal is repetitively read out from the other frame memory (e.g., second memory) in accordance with a synchronizing signal having a desired (target) shorter scanning period. When the write-in operation of the first frame memory is finished, the first frame memory is switched so as to carry out a read-out operation from an address thereof corresponding to a read-out address of the second frame memory at the finishing time of the write-in operation thereof, and the second frame memory which has carried out the read-out operation is switched so as to carry out the write-in operation.

Growing community of inventors

Kanagawa, Japan

Kimio Hatajiri