Optical system for observing equipment having image-vibration compensation system
AssigneeAsahi Kogaku Kogyo Kabushiki Kaisha
InventorsMoriyasu Kanai, Koichi Maruyama
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Abstract
An optical system for a binocular is provided with an objective optical system, an erecting system and an eyepiece. The objective optical system includes a front lens group having positive refractive power, and a rear lens group having negative refractive power. The rear lens group is capable of moving in a direction orthogonal to an optical axis to stabilize an image when the binocular is moved due to hand-held shaking of a user. The objective optical system satisfies the following condition: 0.2<m<4.0 where m is magnification of the rear lens group.
Claims3
An optical system for observing equipment having an image-vibration compensation system, said optical system including an objective optical system comprising:
- a front lens group having positive refractive power;
- and
- a rear lens group having negative refractive power, said lens groups being arranged in the order from an object side,
- wherein:
- said rear lens group is movable in a direction perpendicular to an optical axis of said objective optical system to compensate for a vibration of an image due to a hand-held shaking;
- said rear lens group consists of a single negative aspherical lens of which thickness at its periphery is smaller than that of a spherical lens having the same paraxial radius of curvature;
- and
- condition (1) is satisfied:
- 0.2<m<4.0 (1)
- where m is a magnification of said rear lens group.
An optical system for observing equipment having an image-vibration compensation system, said optical system including an objective optical system comprising:
- a front lens group having positive refractive power;
- and
- a rear lens group having negative refractive power, said lens groups being arranged in the order from an object side,
- wherein:
- said rear lens group is movable in a direction perpendicular to an optical axis of said objective optical system to compensate for a vibration of an image due to a hand-held shaking;
- wherein said rear lens group comprises a positive lens and a negative lens so that chromatic aberration of said rear lens group is corrected;
- and
- condition (1) is satisfied:
- 0.2<m<4.0 (1)
- where m is a magnification of said rear lens group.
Dependencies are inferred from the claim text.