Video projection device having a converter lens attachably and detachably provided
AssigneeKonica Minolta Opto, Inc.
InventorsTokuji Matsuda, Shigeru Sawamura
Life of this patent
Estimating the term…
Abstract
A video projection device has one of a plurality of types of projection lenses replaceably loaded and projects a video on a screen at a fixed position. The video projection device includes: a converter lens which is composed of a plurality of lenses, which is afocal as a whole, and which is detachably provided in front of the projection lens to convert projection magnification; and a gap adjustment mechanism changing a predetermined gap in the converter lens to a setting in accordance with at least one of a projection distance to the screen and the type of the projection lens loaded.
Claims14
A video projection device having one of a plurality of types of projection lenses replaceably loaded and projecting a video on a screen at a fixed position, the video projection device comprising:
- a converter lens comprising a plurality of lenses and being afocal as a whole, the converter lens detachably provided in front of the projection lens to convert projection magnification;
- and
- a gap adjustment mechanism changing a predetermined gap in the converter lens to a setting in accordance with at least one of a projection distance to the screen and the type of the projection lens loaded,
- wherein a video displayed on a video display element based on an electrical video signal is projected on the screen, and
- wherein, in accordance with an aspect ratio of video resources, the converter lens is attached and detached, and also a video region displayed on the video display element is changed.
A video projection device having one of a plurality of types of projection lenses replaceably loaded and projecting a video on a screen at a fixed position, the video projection device comprising:
- a converter lens comprising a plurality of lenses and being afocal as a whole, the converter lens detachably provided in front of the projection lens to convert projection magnification;
- and
- a gap adjustment mechanism changing a predetermined gap in the converter lens to a setting in accordance with at least one of a projection distance to the screen and the type of the projection lens loaded,
- wherein the converter lens is a wide converter lens comprising a front group having negative-negative optical power arrangement and a rear group having positive-negative-positive optical power arrangement, both arrangements being in order from a screen side.
Dependencies are inferred from the claim text.