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Projection lens for projection display systems

US8995062B2 · US · B2

Patent metadata
FieldValue
Publication numberUS-8995062-B2
Application numberUS-201113810894-A
CountryUS
Kind codeB2
Filing dateAug 9, 2011
Priority dateAug 27, 2010
Publication dateMar 31, 2015
Grant dateMar 31, 2015

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  1. Title

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  2. Abstract

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  3. Assignees and inventors

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  4. Key dates

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  5. First independent claim

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  6. CPC / IPC classifications

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  7. Citations and related patents

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Abstract

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Projection lens having improved properties such as a high throughput are described. In one embodiment, a projection lens is described comprising in sequential order from a screen side a first lens group, a second lens group of positive refractive power, and a third lens group of positive refractive power. At least one lens group has an aspheric surface. The ratio of the focal length of the projection lens (F) to the focal length of each of the lens groups (F 1 , F 2 , and F 3 ) is such that |F 1 /F|>5, 0.5<|F 2 /F|<0.9, and 1<F 3 /F<8. In another embodiment, a projection lens is described comprising in sequential order from a screen side a first lens group, a second lens group of positive refractive power, and a third lens group of positive refractive power. At least one lens group has an aspheric surface. The ratio of the focal length of the projection lens (F) to the focal length of each of the lens groups (F 1 , F 2 , and F 3 ) is such that |F 1 /F|>5, 0.5<|F 2 /F|<2.0, and 1.4<F 3 /F<8.

First claim

Opening claim text (preview).

What is claimed is: 1. A projection lens comprising the following components in sequential order from a screen side: (a) a first lens group; (b) a second lens group of positive refractive power; (c) a third lens group of positive refractive power; and at least one lens group has an aspheric surface; wherein F is the focal length of the projection lens; F 1 is the focal length of the first lens group; F 2 is the focal length of the second lens group; F 3 i…

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What does patent US8995062B2 cover?
Projection lens having improved properties such as a high throughput are described. In one embodiment, a projection lens is described comprising in sequential order from a screen side a first lens group, a second lens group of positive refractive power, and a third lens group of positive refractive power. At least one lens group has an aspheric surface. The ratio of the focal length of the proj…
Who is the assignee on this patent?
Yun Zhisheng, Willett Stephen J, 3M Innovative Properties Co
What technology area does this patent fall under?
Primary CPC classification G02B9/62. Mapped technology areas include Physics.
When was this patent published?
Publication date Tue Mar 31 2015 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
What related patents are in patentsdb?
We list 8 related publications on this page (citations in our corpus or others sharing the same primary CPC).