IMAGE DISPLAY DEVICE HAVING BACKLIGHT

• US 20080276109A1
• Filed: 05/01/2008
• Published: 11/06/2008
• Est. Priority Date: 05/02/2007
• Status: Abandoned Application

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: YOSHIDA, Tomonori
• Application Number:
  US12/113,529
• Publication Number:
  US 20080276109A1
• Time in Patent Office: Days
• US Class Current: 713/323
• CPC Class Codes: G09G 2310/063 Waveforms for resetting the whole screen at once
• CPC Class Codes: G09G 2320/04 Maintaining the quality of display appearance
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2320/0633 by amplitude modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2330/022 in absence of operation, e.g. no data being entered during a predetermined time
• CPC Class Codes: G09G 2330/04 Display protection
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336

Abstract

An image display device 1 includes, in a cabinet 2, a liquid crystal display 3 for displaying a video signal, a backlight 6 for irradiating the liquid crystal display 3, a power supply unit 8 for supplying power to the backlight 6, a microcomputer 4 for controlling the power supply, and a temperature sensor 5 for measuring temperature in the cabinet 2 and connected to the microcomputer 4. The microcomputer 4 can be selectively shifted between a standby mode of supplying power only to the microcomputer 4 and the temperature sensor 5 and stopping power supply to other electronic parts and a pseudo standby mode of displaying no image on the liquid crystal display 3 while maintaining light-on of the backlight 6. The microcomputer 4 has a switching function of shifting to the pseudo standby mode when it is determined in the standby mode that temperature data from the temperature sensor 5 is equal to or less than a first threshold value at which dew condensation in the cabinet 2 or an operation failure in an internal electronic part occurs.

Claims

1. An image display device comprising, in a cabinet:

a display for displaying a video signal;

a backlight for irradiating the display;

a power supply unit for supplying power to the backlight;

a microcomputer for controlling the power supply; and

sensor means for measuring temperature in the cabinet and connected to the microcomputer,

wherein the microcomputer can be selectively shifted between a standby mode of supplying power only to the microcomputer and the sensor means and stopping power supply to other electronic parts and a pseudo standby mode of displaying no image by transmitting a dark signal to the display while maintaining light-on of the backlight, and

the microcomputer has a switching function of shifting to the pseudo standby mode when it is determined in the standby mode that temperature data from the sensor means is equal to or less than a temperature corresponding to a first threshold value.

2. The image display device according to claim 1, wherein the microcomputer has a switching function of shifting to the standby mode when it is determined in the pseudo standby mode that temperature data from the sensor means is equal to or higher than a temperature corresponding to a second threshold value, and

the second threshold value indicates a value of temperature higher than the first threshold value.

3. The image display device according to claim 1, wherein the first threshold value is a temperature value at which dew condensation in the cabinet or an operation failure in an internal electronic part occurs.

7. The image display device according to claim 1, wherein the cabinet is hermetically closed and adapted to the outdoor use.

4. An image display device comprising, in a cabinet:

a display for displaying a video signal;

a backlight for irradiating the display;

a power supply unit for supplying power to the backlight a microcomputer for controlling the power supply; and

sensor means for measuring humidity in the cabinet and connected to the microcomputer,

wherein the microcomputer can be selectively shifted between a standby mode of supplying power only to the microcomputer and the sensor means and stopping power supply to other electronic parts and a pseudo standby mode of displaying no image by transmitting a dark signal to the display while maintaining light-on of the backlight, and

the microcomputer has a switching function of shifting to the pseudo standby mode when it is determined in the standby mode that humidity data from the sensor means is equal to or higher than a humidity corresponding to a first threshold value.

5. The image display device according to claim 4, wherein the microcomputer has a switching function of shifting to the standby mode when it is determined in the pseudo standby mode that humidity data from the sensor means is equal to or lower than a humidity corresponding to a second threshold value, and

the second threshold value indicates a value of humidity lower than the first threshold value.

6. The image display device according to claim 4, wherein the first threshold value is a humidity value at which dew condensation in the cabinet or an operation failure in an internal electronic part occurs.

8. The image display device according to claim 4, wherein the cabinet is hermetically closed and adapted to the outdoor use.