The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 02, 2003
Filed:
Mar. 30, 2001
Keiji Hayashi, Kawasaki, JP;
Takeshi Gotoh, Kawasaki, JP;
Toshihiro Suzuki, Kawasaki, JP;
Hisashi Yamaguchi, Kawasaki, JP;
Tetsuya Kobayashi, Kawasaki, JP;
Tetsuya Hamada, Kawasaki, JP;
Mari Sugawara, Kawasaki, JP;
Fujitsu Display Technologies Corporation, Kawasaki, JP;
Abstract
The invention relates to a backlight unit for liquid crystal displays, etc.; and its object is to provide a backlight unit not involving the problem that the emitted light leaks out of the optical waveguide, even when the space around the cold-cathode tubes in the light source unit for it is filled with a liquid of which the refractive index is nearly the same as that of the glass material that forms the outer wall of the cold-cathode tubes. The backlight unit comprises a housing which houses cold-cathode tubes therein and of which the inner surface is coated with a light reflector a transparent liquid filled in the housing and an optical waveguide made of a transparent substance and having a light-emitting surface S. The reflective surface of the light reflector has a cross-section profile of X-T-U-V-W-Y, on which the light emitted by the cold-cathode tubes is reflected, and the thus-reflected light is led to the light-emitting surface S of the optical waveguide at an incident angle not smaller than the critical angle to the surface S.