Lighting device and display device

Patent metadata

Field	Value
Publication number	US-2018024290-A1
Application number	US-201615551760-A
Country	US
Kind code	A1
Filing date	Feb 12, 2016
Priority date	Feb 19, 2015
Publication date	Jan 25, 2018
Grant date	—

Abstract

A lighting device includes a light guide plate 14 having a light exit surface 14A. having a substantially circular shape and a light entrance surface 14C extending along an entire periphery of an outer edge of the light exit surface 14A, an LED 31A opposite the light entrance surface 14C, and an LED 32A that is opposite the light entrance surface 14C and is connected in parallel to the LED 31A and the LED 32A is arranged opposite from the LED 31A with having a center C1 of the light exit surface 14A therebetween,

First claim

1 . A lighting device comprising:
a light guide plate having a light exit surface having a substantially circular shape and a light entrance surface extending along an entire periphery of an outer edge of the light exit surface; a first light source opposite the light entrance surface; and a second light source opposite the light entrance surface, the second light source that is connected in parallel to the first light source or connected to a power supply different from a power supply that is connected to the first light source, the second light source arranged opposite from the first light source with having a center of the light exit surface therebetween.

2 . The lighting device according to claim 1 , wherein
the first light source includes first light sources that are arranged in a circumferential direction of the light entrance surface, the first light sources are connected in series, the second light source includes second light sources that are arranged in the circumferential direction of the light entrance surface, and the second light sources are connected in series,

3 . The lighting device according to claim 2 , wherein the first light sources and the second light sources are arranged alternately in the circumferential direction of the light entrance surface.

4 . The lighting device according to claim 2 , wherein
the first light sources are arranged at equal intervals in an annular shape having a center corresponding to the center of the light exit surface and a number of the first light sources is an odd number, and the second light sources are arranged at equal intervals in an annular shape having a center corresponding to the center of the light exit surface and a number of the second light sources is an odd number,

5 . The lighting device according to claim 2 , wherein
the first light sources and the second light sources are at least included in light sources, a total number of the light sources is an even number, and the light sources are arranged at equal intervals in an annular shape having a center corresponding to the center of the light exit surface.

6 . The lighting device according to claim 2 wherein
the first light sources and the second light sources are at least included in light sources,
a total number of the light sources is an odd number,
the light sources are arranged at equal intervals in an annular shape having a center corresponding to the center of the light exit surface, and
a value obtained by (R 1 *circumference of ratio)/N is 10 mm or less, R 1 is a distance between each of the light sources and the center of the light exit surface, and N is the total number of the light sources.

7 . A display device comprising:
the lighting device according to claim 1 ; and a display panel display with using light from the lighting device.

Assignees

• Sharp Kk

Inventors

• Watanabe Hisashi
• Yuki Ryuzo
• Kadowaki Shinya
• Murata Mitsuhiro
• Ishida Takeshi
• Masuda Takeshi

Classifications

• G02B6/0068 Primary

  Arrangements of plural sources, e.g. multi-colour light sources · CPC title

• G02B6/0091

  of the light source relative to the light guide (G02B6/0021 takes precedence) · CPC title

• G02B6/005

  provided by one optical element, or plurality thereof, placed on the light output side of the light guide · CPC title

• G02B6/0083 Primary

  Details of electrical connections of light sources to drivers, circuit boards, or the like · CPC title