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:
Jan. 17, 2012
Filed:
Mar. 27, 2007
Sadanori Yamanaka, Tsukuba, JP;
Yoshinobu Ono, Tsukubamirai, JP;
Kazumasa Ueda, Tsuchiura, JP;
Sumitomo Chemical Company, Limited, Tokyo, JP;
Abstract
The present invention provides a light emitting device. The light emitting device has a light distribution in which a light distribution I (θ, φ) obtained when light emitted from a chip of the light emitting device is directly measured is not dependent on a direction φ and is substantially represented by I (θ, φ)=I (θ). I (θ, φ) represents a light intensity distribution in a direction (θ, φ), θ represents an angle from a direction of a normal to a light extraction surface of the light emitting device (0≦θ≦90°), φ represents a rotation angle around the normal (0≦φ≦360°), and I (θ) represents a monotone decreasing function with which 0 is approached when θ=90° is satisfied. In the light emitting device, of a structural body constructing the chip of the light emitting device, with regard to a size of a portion of the structural body which is transparent to light emitted from a light emitting layer, a ratio (an aspect ratio) between the size in a lateral direction and the size in a thickness direction is not less than 5 and a structure having a light scattering function is provided on a surface of the light emitting device chip or in an interior of the transparent portion of the structural body.