Projection lens unit
AssigneeKonica Minolta Opto, Inc.
InventorsAtsuo Masui, Tokuji Matsuda, Kohei Wataru
Life of this patent
Estimating the term…
Abstract
A projection lens system 1A enlarges and projects onto a screen 8, via a plurality of lenses G1 to G16, image light emitted from, a light source 4 and modulated by DMDs 3r to 3b. A movable lens barrel 25 holds the lens G16, having positive power, which is positioned closest to the DMDs 3r to 3b. An outer tube 24 holds the movable lens barrel 25 to enable movement in the optical axis direction. Through thermal deformation at the time of an increase in temperature, the bimetal member 27 moves the movable lens barrel 25 in the optical axis direction so as to recede from the image formation devices which are the DMDs 3r to 3b.
Claims24
A projection lens unit comprising:
- a projection lens system which enlarges and projects image light from an image formation device onto a screen;
- and a lens barrel which holds lenses of the projection lens system, wherein
- the lens barrel comprises:
- a movable lens barrel which holds one or a plurality of lenses, among the lenses of the projection lens system, having positive power and positioned closest to a side of the image formation device;
- a holding tube which holds the movable lens barrel so as to be movable in an optical axis direction;
- a reference surface perpendicular to the optical axis;
- a thermal deformation member including a bimetal member which is deformed so as to increase a thickness thereof at the time of a temperature increase and which is disposed between the reference surface and the movable lens barrel;
- and
- an elastic member which presses the movable lens barrel and the bimetal member in the optical axis direction toward the image formation device against the reference surface.
A projection lens unit comprising a projection lens system which enlarges and projects light from an image formation device onto a screen and a lens barrel which holds lenses of the projection lens system, wherein the lens barrel comprises:
- a movable lens barrel which holds one or a plurality of lenses, among the lenses of the projection lens system, having positive power and positioned closet to a side of the imager formation device;
- a holding tube which holds the movable lens barrel so as to be movable in an optical axis direction;
- a reference surface perpendicular to the optical axis;
- a thermal deformation member including a bimetal member which is deformed so as to decrease thickness thereof at the time of a temperature increase and which is disposed between the reference surface and the movable lens barrel;
- and
- an elastic member which presses the movable lens barrel and the bimetal member in the optical axis direction toward the screen against the reference surface.
A projection lens unit comprising:
- a projection lens system which enlarges and projects image light from an image formation device onto a screen;
- and a lens barrel which holds lenses of the projection lens system, wherein the lens barrel comprises:
- a movable lens barrel which holds one or a plurality of lenses, among the lenses of the projection lens system, having positive power and positioned closest to a side of the image formation device;
- a holding tube which holds the movable lens barrel, so as to be movable in an optical axis direction;
- and
- a thermal deformation member which, through thermal deformation at the time of a temperature increase, moves the movable lens barrel in the optical axis direction so as to recede from the image formation device;
- and
- a rotation-halting mechanism which impedes rotation of the movable lens barrel about the optical axis relative to the holding tube, and which enables setting of the rotational position of the movable lens barrel about the optical axis relative to the holding tube to a plurality of positions.
Dependencies are inferred from the claim text.