【発明の名称】防振光学系

Japanese Patent JP2722622

B2

A vibration-isolating optical system having an image stabilizing function, comprising: a fixed lens optical system having a plurality of lens groups which are arranged to be stationary in the vertical direction with respect to the optical axis; and a vibration-isolating compensating optical system disposed adjacently to the image of the fixed lens optical system and arranged to be movable in a direction intersecting the optical axis, wherein the vibration-isolating compensating optical system is constituted by, in sequence order from the portion adjacent to the object, a first factor formed by a double convex positive lens, a second factor formed by a negative lens whose concave surface confronts the object, and a third factor formed by a positive lens. The vibration-isolating compensating optical system is arranged so as to meet the following relationships, assuming that the power (the reciprocal of the focal length) of the overall body of the vibration-isolating compensating optical system is phi , the power of the first factor is phi 1, the power of the second factor is phi 2 and the combination power of the first factor and the second factor is phi 12: ¦ phi 12¦