US 5,291,241 A · Optical device

Abstract

In an imaging apparatus, a magnified image of an object is formed on a predetermined plane through a plurality of lens groups. A plurality of filters are selectively inserted into the light path between the object and the predetermined plane. An optical device is provided in the imaging apparatus, in which the plurality of lens groups are driven as a unit along the optical axis while the positional relation among the respective lens groups are correspondingly changed, wherein at least one of the plurality of lens groups is independently driven along the optical axis. The plurality of lens groups are driven to move in accordance with a desired image magnification, and at-least-one of the plurality of lens groups is independently driven, depending upon the selected filter, so as to place the object image on the predetermined plane.

Claims20

Dependent claims

An optical device employed in an imaging apparatus in which an image of an object is formed on a predetermined plane through a plurality of lens groups, said plurality of lens groups being coaxially arranged and used for changing the magnification of said object image formed on said predetermined plane, a plurality of filters for respectively allowing predetermined colors of light to pass therethrough being selectively inserted into the light path between said object and said predetermined plane, said optical device comprising:

first drive means for driving said plurality of lens groups as a unit along the optical axis thereof while correspondingly changing the positional relation among the respective lens groups;
second drive means for independently driving at least one of said plurality of lens groups along said optical axis;
first control means for controlling said first and second drive means to drive said plurality of lens groups in accordance with a desired image magnification;
and
second control means for controlling said second drive means to drive said at-least-one of said plurality of lens groups, depending upon the selected filter, so as to place the object image on said predetermined plane.

2 more elements

An optical device for use in an imaging apparatus in which an image of an object is formed on a predetermined plane by a plurality of lens groups, a magnification of the image formed on the predetermined plane can be changed, including a plurality of filters for allowing predetermined colors of light to pass therethrough, a selected filter of the plurality of filters being selectively insertable into a light path between the object and the predetermined plane, said optical device comprising:

first means for driving said plurality of lens groups along an optical axis of said plurality of lens groups and for moving a predetermined lens group of said plurality of lens groups with respect to said plurality of lens groups along the optical axis;
second means, independent of said first means, for driving a specific lens group of said plurality of lens groups along the optical axis with respect to said plurality of lens groups;
first control means, for controlling said first and second drive means to drive said plurality of lens groups to change an image magnification to a predetermined image magnification;
and
second control means, for controlling said second drive means to drive said specified lens group of said plurality of lens groups, in accordance with insertion of a selected filter into the light path so as to form the image on the predetermined plane.

2 more elements

Dependencies are inferred from the claim text.

Optical device

Life of this patent

Optical device

Life of this patent

Abstract

Claims20