US 7,488,104 B2
Backlight unit and liquid crystal display device having the same
Tetsuya Hamada, Kanagawa (Japan); Toshihiro Suzuki, Kanagawa (Japan); and Masaru Ishiwa, Kanagawa (Japan)
Assigned to Sharp Kabushiki Kaisha, Osaka (Japan)
Filed on Nov. 21, 2006, as Appl. No. 11/562,181.
Application 11/562181 is a continuation of application No. PCT/JP2005/005952, filed on Mar. 29, 2005.
Claims priority of application No. 2004-151963 (JP), filed on May 21, 2004; application No. 2004-322184 (JP), filed on Nov. 05, 2004; and application No. 2005-053978 (JP), filed on Feb. 28, 2005.
Prior Publication US 2007/0153548 A1, Jul. 05, 2007
Int. Cl. F21V 8/00 (2006.01)
U.S. Cl. 362—616  [362/612; 362/631; 362/561] 56 Claims
OG exemplary drawing
 
1. A backlight unit comprising:
a discrete light source section, a reflecting section, a light guide section, a first optical mixing section, and a second optical mixing section; wherein
the reflecting section, the light guide section, the first optical mixing section, and the second optical mixing section are overlaid in this order;
the discrete light source section includes individual light sources having different spectra or different light emission quantities arranged near an incident plane of the light guide section;
a light drawing section configured to take a light propagating through the light guide section out on a reflecting section side or on a first optical mixing section side is provided on a surface of the light guide section facing the reflecting section or a surface facing the first optical mixing section;
the first optical mixing section is configured to mix color lights of different spectra or lights of different light quantities substantially in an in-plane direction to make the light uniform; and
the second optical mixing section is configured to mix lights at different angles in a same point in a plane to angularly realign the light to make a luminous light color and a luminous light quantity uniform in the plane.