Claims
- 1. A method of designing a broadband diffractive diffuser comprising:
- generating a first diffractive diffuser pattern at a design wavelength; and
- modifying the first diffractive diffuser pattern to provide light at a wavelength other than the design wavelength with more phasor vectors at zero order than light at the design wavelength, said modifying including generating a second diffractive diffuser pattern and adding phases of said second diffuser pattern to corresponding phases of said first diffractive diffuser pattern, wherein said first diffractive diffuser pattern forms an undersized desired output, said second diffractive diffuser pattern forms a spot, and a modified pattern formed by adding phases of said second diffractive diffuser pattern and said first diffractive diffuser pattern generates a desired output.
- 2. The method according to claim 1, wherein said modifying includes performing an operation between regions of said first diffractive diffuser pattern which present a zero phase shift and said second different diffractive diffuser pattern.
- 3. The method according to claim 2, wherein said generating said second diffractive diffuser pattern includes rotating said first diffractive diffuser pattern.
- 4. The method according to claim 2, wherein said operation is an add operation.
- 5. The method according to claim 1, wherein said generating includes iterative computer optimizing.
- 6. The method according to claim 1, wherein said generating includes splitting the diffuser into regions having a phase shift of .pi. and regions having a phase shift of zero at the design wavelength, and said modifying includes splitting regions having a phase shift of zero into regions having a phase shift of zero and regions having a phase shift of 2.pi. at the design wavelength.
- 7. The method according to claim 6, wherein at least one of said splittings is even.
- 8. The method according to claim 6, wherein at least one of said splittings results in amorphous regions.
- 9. The method according to claim 6, wherein said splittings include a pixel-by-pixel search.
- 10. The method according to claim 1, wherein said generating and modifying are performed on a computer to form a computer generated hologram.
- 11. The method according to claim 1, further comprising photolithographically creating a modified diffractive diffuser pattern output by said modifying.
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation in part of U.S. application Ser. No. 08/770,524 filed on Dec. 20, 1996 entitled "Beam Homogenizer", now U.S. Pat. No. 5,850,300, the entire contents of which are hereby incorporated by reference.
US Referenced Citations (18)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0 744 664 A2 |
Nov 1996 |
EPX |
Continuation in Parts (1)
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Number |
Date |
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Parent |
770524 |
Dec 1996 |
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