IMAGE DISPLAY DEVICE

• US 20110221714A1
• Filed: 02/17/2011
• Published: 09/15/2011
• Est. Priority Date: 03/15/2010
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: KURIAKI, Makoto
• Granted Patent: US 8,570,317 B2
• Time in Patent Office: Days
• US Class Current: 345/204
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2330/045 Protection against panel overheating
• CPC Class Codes: G09G 3/02 by tracing or scanning a light beam on a screen

Abstract

There is provided an image display device including: a laser element that generates light for projecting and displaying an image on a display screen; a Peltier device unit that cools the laser element; a detecting unit that detects a temperature of the laser element; and a control unit that controls driving of the Peltier device unit so that a temperature detected by the detecting unit becomes a target temperature, wherein the control unit controls driving of the laser element to reduce a light output of the laser element when a driving rate of the Peltier device unit exceeds a threshold that indicates that the driving rate approaches a maximum value.

Claims

1. An image display device comprising:

a laser element that generates light for projecting and displaying an image on a display screen;

a Peltier device unit that cools the laser element;

a detecting unit that detects a temperature of the laser element; and

a control unit that controls driving of the Peltier device unit so that a temperature detected by the detecting unit becomes a target temperature, wherein

the control unit controls driving of the laser element to reduce a light output of the laser element when a driving rate of the Peltier device unit exceeds a threshold that indicates that the driving rate approaches a maximum value.

2. The image display device according to claim 1, further comprising:

a second detecting unit that detects a light output of the laser element; and

a projection display unit that receives light output from the laser element to project and display an image on the display screen, wherein

the control unit controls the projection display unit to project and display a warning on the display screen when a light output detected by the second detecting unit becomes lower than a second threshold.

3. The image display device according to claim 1, wherein the control unit controls the driving of the laser element to increase a light output of the laser element when a duration of a state, in which a driving rate of the Peltier device unit becomes lower than the threshold, is longer than a third threshold.

4. The image display device according to claim 2, wherein the control unit controls the driving of the laser element to increase a light output of the laser element when a duration of a state, in which a driving rate of the Peltier device unit becomes lower than the threshold, is longer than a third threshold.