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:
May. 19, 2015
Filed:
Aug. 21, 2013
Chieko Hatashita, Kanagawa, JP;
Takayuki Nakamura, Kanagawa, JP;
Hiroshi Nakanuma, Kanagawa, JP;
Kentaroh Hagita, Miyagi, JP;
Chieko Hatashita, Kanagawa, JP;
Takayuki Nakamura, Kanagawa, JP;
Hiroshi Nakanuma, Kanagawa, JP;
Kentaroh Hagita, Miyagi, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An optical element using visible light from wavelengths λS to λL (λL>λS), is formed of a translucent material having refractive indexes nS and nL, respectively, for light having the wavelengths λS and λL. The optical element includes an incident face; an exit face; and a micro convexo-concave structure used as an anti-reflection structure (ARS), being formed at least one of the incident face and the exit face. An average distance P between adjacent micro convexo-concave structures satisfies condition (1) P≦0.8·λS/nS. Dimensionless parameters mS and mL satisfy condition (2) 0.8≦mS≦1.1 and condition (3) 0.8≦mL≦1.1. The parameters mS and mL, an average height H, the wavelengths λS and λL, and the refractive indexes nS and nL of the micro convexo-concave structure satisfy condition (4) mS·λS/(2·nS)≦H≦mL·λL/(2·nL).