Patent ID: 6179447
Filing Date: 2001-01-30
Classification: F21V,G02B,G03B

Abstract:
A light distribution lens for a strobe which is located in front of a strobe light emitter, comprising:a convex surface which is provided on one surface of said light distribution lens; anda convex Fresnel surface which is provided on the other opposing lens surface of said light distribution lens;wherein said Fresnel surface is provided with annuluses, each being defined by a cylindrical surface having an axis coincident with an optical axis of said light distribution lens and a conical surface to define a wedge shape in cross section;wherein said light distribution lens satisfies the following relationship;.theta..ltoreq.10 Hwherein H represents the distance, in millimeters, of each annulus of the convex Fresnel surface from the optical axis, and .theta. represents an angle, in degrees, defined by a wedge surface of each annulus and a plane perpendicular to the optical axis, respectively.