Wide field of view projection lenses for compact projection lens systems employing pixelized panels
First Claim
1. A projection lens for forming an image of an object, said projection lens having a focal length f0 and consisting in order from its image side of:
- (A) a first lens unit having a focal length f1 and comprising;
(i) a lens element having a focal length fE1; and
(ii) at least one aspherical surface for correction of distortion; and
(B) a second lens unit having a focal length f2 and consisting in order from its image side of;
(i) a first lens subunit having a focal length f2S1; and
(ii) a second lens subunit separated from the first lens subunit by an airspace and having a focal length f2S2, said second lens subunit comprising;
(a) at least one aspherical surface for correction of spherical aberration, and (b) means for providing axial color correction for the lens system;
wherein;
2 Assignments
0 Petitions
Accused Products
Abstract
A projection lens for use with LCD panels is provided. The lens has a first lens unit which includes a strong negative lens element having an aspherical surface which provides distortion correction, and a second lens unit which includes a first lens subunit separated by an airspace from a second lens subunit, wherein the first lens subunit has a strong positive power and the second lens subunit has a weaker power. The second lens subunit can include a negative lens element, followed by a positive lens element, followed by a plastic lens element having an aspherical surface. The projection lens has a field of view of at least 35° so that the overall projection lens system has a compact size.
120 Citations
16 Claims
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1. A projection lens for forming an image of an object, said projection lens having a focal length f0 and consisting in order from its image side of:
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(A) a first lens unit having a focal length f1 and comprising;
(i) a lens element having a focal length fE1; and
(ii) at least one aspherical surface for correction of distortion; and
(B) a second lens unit having a focal length f2 and consisting in order from its image side of;
(i) a first lens subunit having a focal length f2S1; and
(ii) a second lens subunit separated from the first lens subunit by an airspace and having a focal length f2S2, said second lens subunit comprising;
(a) at least one aspherical surface for correction of spherical aberration, and (b) means for providing axial color correction for the lens system;
wherein;
- View Dependent Claims (6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
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2. A projection lens for forming an image of an object, said projection lens having a focal length f0 and consisting in order from its image side of:
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(A) a first lens unit having a focal length f1 and comprising;
(i) a lens element having a focal length fE1; and
(ii) at least one aspherical surface for correction of distortion; and
(B) a second lens unit having a focal length f2 and consisting in order from its image side of;
(i) a first lens subunit having a focal length f2S1; and
(ii) a second lens subunit separated from the first lens subunit by an airspace and having a focal length f2S2, said second lens subunit consisting in order from its image side of;
(a) a negative lens element, (b) a positive lens element, and (c) a plastic lens element having at least one aspherical surface;
wherein;
- View Dependent Claims (3, 4, 5)
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Specification