Patent ID: 6154312
Filing Date: 2000-11-28
Classification: G02B

Abstract:
An objective lens switching device comprising:a turret on which a plurality of objective lenses are mountable;drive means for electrically revolving the turret;transfer means for transferring a revolving force from the drive means to the turret;engaging means for accurately positioning one of the plurality of objective lenses on an optical axis of an optical apparatus;operating means for inputting an objective lens switching command; andcontrol means for controlling rotation of the drive means according to the switching command input by the operating means,wherein one of the plurality of objective lenses is selected and positioned on the optical axis of the optical apparatus,wherein the objective lens switching device further comprises engagement detecting means for detecting that a revolution position of the turret is in an engagement range of the engaging means, and angle detecting means for detecting an angular displacement of the drive means, andwherein the control means performs braking of the drive means to drive the turret at a low speed after the angle detecting means detects a first angle of revolution which is smaller than a necessary angle of revolution of the turret according to the switching command input by the operating means, and then the control means performs braking to completely stop the drive means after the angle detecting means detects a second angle of revolution larger than the first angle of revolution.