Patent ID: 6560032
Filing Date: 2003-05-06
Classification: G02B

Abstract:
A low magnification liquid immersion objective lens system which uses an immersion liquid having a refractive index ND within a range defined by a condition (1) shown below, comprising in order from the object side, a first lens unit having positive refractive power and at least another lens unit, and satisfying the following conditions (2), (3) and (4):1.34&lE;ND&lE;1.80â€ƒâ€ƒ(1) &bgr;&lE;15â€ƒâ€ƒ(2) WDL&lE;0.35 mmâ€ƒâ€ƒ(3) |fÂ·&bgr;/fG1|&lE;40â€ƒâ€ƒ(4) wherein a reference symbol &bgr; represents a magnification of said objective lens system, a reference symbol WDL designates a working distance of said objective lens system, a reference symbol fG1 represents a focal length of the first lens unit and a reference symbol f designates a focal length of said objective lens system.