Patent ID: 6690518
Filing Date: 2004-02-10
Classification: G02B

Abstract:
A camera-attachment lens system that is provided behind an objective optical system, and is arranged to relay a real image formed by said objective optical system, and to re-form a real image, said camera-attachment lens system comprising a positive condenser lens and a positive image-forming lens system, in this order from said objective optical system;wherein said camera-attachment lens system satisfies the following conditions: 1.52.4 0.080.16 1.65â€ƒwherein fa designates the combined focal length of said condenser lens and said image-forming lens system without any intervening lenses; fco designates the focal length of said condenser lens; DO designates the distance, along the optical axis, from said image-forming plane of said objective optical system to the most objective-optical-system side surface of said condenser lens; and Nco designates the refractive index of the condenser lens.