Illumination device and display device including the same

• US 8,982,165 B2
• Filed: 08/09/2012
• Issued: 03/17/2015
• Est. Priority Date: 08/11/2011
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Yabuta, Junko
• Primary Examiner(s): Tran, Thuy Vinh
• Assistant Examiner(s): Kaiser, Syed M
• Application Number:
  US13/570,707
• Publication Number:
  US 20130038212A1
• Time in Patent Office: 950 Days
• Field of Search: 315/113, 345/102, 345/204, 345/207, 345/690
• US Class Current: 345/690
• CPC Class Codes: G02F 1/133601 for spatial active dimming
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133611 including means for improving the brightness uniformity
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/24 using electrical feedback from LEDs or from LED modules

Abstract

An illumination device includes a light source in which a plurality of light emitting elements are arranged, a luminous intensity controller configured to control luminous intensities of the plurality of light emitting elements separately in groups of one or more light emitting elements, and a predetermined correction table indicating temperature distribution characteristics corresponding to position information of the plurality of light emitting elements in the light source. The luminous intensity controller controls the luminous intensities of the plurality of light emitting elements corresponding to the position information based on the temperature distribution characteristics of the correction table.

Claims

1. An illumination device comprising:

a light source in which a plurality of light emitting elements are arranged;

a luminous intensity controller configured to control luminous intensities of the plurality of light emitting elements separately in groups of one or more light emitting elements; and

a predetermined correction table indicating temperature distribution characteristics corresponding to position information of the plurality of light emitting elements in the light source, wherein

the luminous intensity controller controls the luminous intensities of the plurality of light emitting elements corresponding to the position information in accordance with the temperature distribution characteristics of the correction table, and

the luminous intensity controller controls the luminous intensities of the plurality of light emitting elements based on temperature differences between temperature settings at positions corresponding to the plurality of light emitting elements in the temperature distribution characteristics of the correction table, and a reference temperature which is used as a reference for a luminous intensity control of controlling the luminous intensity.

2. The illumination device according to claim 1, wherein

the luminous intensity controller decreases the luminous intensities of any one or more of the plurality of light emitting elements that have characteristics indicating a negative correlation between the temperature and the luminous intensity and have a lower temperature setting than the reference temperature, by an amount corresponding to the temperature difference.

3. The illumination device according to claim 1, wherein

the luminous intensity controller increases the luminous intensities of any one or more of the plurality of light emitting elements that have characteristics indicating a negative correlation between the temperature and the luminous intensity and have a higher temperature setting than the reference temperature, by an amount corresponding to the temperature difference.

4. The illumination device according to claim 2, wherein

the reference temperature is a highest temperature setting in the temperature distribution characteristics.

5. The illumination device according to claim 1, further comprising:

a plurality of light emitting element groups each including the plurality of light emitting elements, wherein

the plurality of light emitting elements in the plurality of light emitting element groups emit light having colors that differ among the plurality of light emitting element groups,

the light source emits light having a predetermined color by combining light beams of the plurality of light emitting elements in the plurality of light emitting element groups, and

the luminous intensity controller controls the luminous intensities of the plurality of light emitting elements in each of the plurality of light emitting element groups, separately in groups of one or more light emitting elements.

6. A display device comprising the illumination device according to claim 1.

7. The display device according to claim 6, wherein

a display image of the display device is divided into sub-regions, and the luminous intensity controller controls the luminous intensities of any one or more of the plurality of light emitting elements that correspond to each of the sub-regions based on a lightness or darkness of the each of the sub-regions.