Patent ID: 6744563
Filing Date: 2004-06-01
Classification: G02B

Abstract:
A collimating lens, comprisinga lens having at least one aspherical surface, wherein the collimating lens is used in a wavelength range of 1.2 &mgr;m to 1.7 &mgr;m and satisfies the following conditions: 226&lE;x&lE;456 and y&lE;1.8, wherein where x is an infrared distribution indicator defined byx=(n(1.55)âˆ’1)/(n(1.45)âˆ’n(1.65)), y is an index of refraction at a wavelength of 1.55 &mgr;m shown by y=n(1.55), and n(a) is an index of refraction at wavelength of a.