Projection optical device
AssigneeMinolta Co., Ltd.
InventorSoh Ohzawa
Life of this patent
Estimating the term…
Abstract
A projection optical device includes a projection optical system for projecting an image of an object plane onto a screen without forming an intermediate real image. The projection optical system includes a coaxial first lens group to be arranged relatively near the object plane, a coaxial second lens group to be arranged relatively near the screen, and a stop arranged between the first and second lens groups. The second lens group has an optical axis inclined with respect to an optical axis of the first lens group. A magnification .beta.1 of the first lens group satisfies a relationship of .vertline.1/.beta.1.vertline.<0.05. The second lens group is angularly deviated from the first lens group around a position of the stop.
Claims20
A projection optical device comprising a projection optical system for projecting an image of an object plane onto a screen without forming an intermediate real image, wherein said projection optical system includes a coaxial first lens group to be arranged relatively near the object plane, a coaxial second lens group to be arranged relatively near said screen, and a stop arranged between said first and second lens groups, said second lens group has an optical axis inclined with respect to an optical axis of said first lens group, and a magnification .beta.1 of said first lens group satisfies a relationship of .vertline.1/.beta.1.vertline.<0.05.
A projection optical device for projecting an image of an object plane onto a screen without forming an intermediate real image, comprising:
- information providing means for providing information to the object plane;
- a coaxial first lens group to be arranged relatively near the object plane;
- a coaxial second lens group to be arranged relatively near the screen and having an optical axis inclined with respect to an optical axis of said first lens group;
- a stop arranged between said first and second lens groups;
- and
- said screen onto which the information on the object plane provided by said information providing means is projected,
- a magnification .beta.1 of said first lens group satisfying a relationship of .vertline.1/.beta.1.vertline.<0.05.
A projection optical device having a projection optical system for projecting an image of an object plane onto a screen, said projection optical system comprising, from the object plane side:
- a first lens group to be arranged relatively near the object plane;
- a second lens group to be arranged relatively near the screen;
- and
- a stop arranged between said first and second lens groups,
- wherein at least one of said first and second lens groups is angularly deviatable, and
- wherein said angularly deviatable lens group is operable to turn for turning one of an image plane and the object plane while maintaining a constant distortion of the image plane.
A projection optical device for projecting an image of an object plane onto a screen, comprising:
- information providing means for providing information to the object plane;
- a first lens group to be arranged relatively near the object plane;
- a second lens group to be arranged relatively near the screen;
- a stop arranged between said first and second lens groups;
- and
- wherein said screen onto which the information on the object plane provided by said information providing means is projected, and
- at least one of said first and second lens groups is angularly deviatable, and said angularly deviatable lens group being operable to turn for turning one of an image plane and the object plane while maintaining a constant distortion.
Dependencies are inferred from the claim text.