Projection system with an offset lens array to reduce vertical banding
AssigneeAurora Systems, Inc.
InventorsMatthew F. Bone, Isabella T. Lewis
Life of this patent
Estimating the term…
Abstract
The mechanism of and a solution to the problem of vertical banding in projection systems is disclosed. An offset lens array includes a plurality of lens elements arranged in a plurality of rows that are offset with respect to one another. The offset lens array is incorporated in an illuminator for a projection system. The asymmetrical arrangement of the rows of lens elements in the array with respect to a seam in a color separation element of the projection system substantially reduces the vertical banding in the projected image.
Claims17
An illumination system comprising:
- a light source for emitting a beam of light;
- a first lens array including a plurality of lens elements arranged in a plurality of rows, at least two of said rows of lens elements being horizontally offset with respect to one another;
- a second lens array including a plurality of lens elements arranged as the elements of said first lens array, said second lens array disposed a spaced distance from said first lens array, such that each lens element of said first lens array focuses a portion of said beam of light through a corresponding lens element of said second lens array;
- and
- a polarization conversion element disposed adjacent said second lens array to polarize the portions of said light beam passing through said second lens array;
- and
- wherein
- starting with a top row of said first lens array, each successive row of said lens elements is horizontally offset with respect to the preceding row of said lens elements by the same distance, thereby forming nonvertical columns of lens elements in said first lens array;
- starting with a top row of said second lens array, each successive row of said lens elements is horizontally offset with respect to the preceding row of said lens elements by the same distance, thereby forming nonvertical columns of lens elements in said second lens array;
- and
- said polarization conversion element is rotated about an axis passing through said first lens array, said second lens array, and said polarizing conversion element such that the polarizing channels of said polarization conversion elements align with said nonvertical columns of said lens elements.
An illumination system comprising:
- a light source for emitting a beam of light;
- a first lens array including a plurality of lens elements arranged in a plurality of rows, at least two of said rows of lens elements being horizontally offset with respect to one another;
- and
- a second lens array including a plurality of lens elements arranged as the elements of said first lens array, said second lens array disposed a spaced distance from said first lens array, such that each lens element of said first lens array focuses a portion of said beam of light through a corresponding lens element of said second lens array;
- and
- wherein adjacent rows of said lens elements of said first array are horizontally off set with respect to one another;
- and
- wherein adjacent rows of said lens elements of said second lens array are horizontally offset with respect to one another.
A projection system comprising:
- an illumination source for emitting an illumination beam, said illumination source including a lens array having a plurality of lens elements;
- and
- a color separating element for separating said illumination beam into a plurality of colored illumination beams, said color separating element having a seam therein;
- and
- wherein said lens array is arranged asymmetrically with respect to said seam.
Dependencies are inferred from the claim text.