Patent US6025938A successfully refreshed from Google Patents.
US6025938A
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Beam homogenizer
Assignee: Avago Technologies International Sales Pte Ltd
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Filing: 1998-09-25
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Granted: 2000-02-15
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Expires: 2018-09-25
Abstract
Abstract A beam homogenizer that minimizes undesired intensity variations at the output plane caused by sharp breaks between facets in previous embodiments. The homogenizer includes a hologram made up of irregularly patterned diffractive fringes. An input beam illuminates at least part of the hologram. The hologram transmits a portion of the input beam onto an output plane. In doing so, the energy of the input beam is spatially redistributed at the output plane into a homogenized output beam having a preselected spatial energy distribution at the output plane. Thus, the illuminated portion of the output plane has a shape predetermined by the designer of the homogenizer.
Inventors
- 👤 Alan D Kathman
- 👤 Michael R. Feldman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:34
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/02; G02B5/0205; G02B5/0252; G02B27/00; G02B27/09; G02B27/0905; B; B23; B23K; B23K26/00; B23K26/02; B23K26/06; B23K26/064; B23K26/0643; B23K26/0648; B23K26/066; B23K26/0665; G02B19/00; G02B19/0004; G02B19/0009; G02B19/0014; G02B19/0033; G02B19/0047; G02B19/0052; G02B19/0057; G02B19/0095; G02B27/0927; G02B27/0938; G02B27/0944; G02B5/0273; G02B5/0278; G02B5/18; G02B5/1814; G02B5/1819; G02B5/1847; G02B5/1857; G02B5/32; G03; G03F; G03F7/00; G03F7/70; G03F7/70058; G03H; G03H1/00; G03H1/22; G03H1/2286; H; H04; H04B; H04B10/00; H04B10/50; G03H1/02; G03H1/0236; G03H1/04; G03H1/08; G03H1/0841; G03H2001/085; G03H1/26; G03H1/30; G03H2001/303; G03H2222/00; G03H2222/35; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
48 words
A diffractive element comprising: a computer-generated hologram comprising irregularly patterned diffractive fringes and having a phase-transmittance pattern in which a Fourier transform of the phase transmittance pattern is more uniform than a Fourier transform of a phase transmittance pattern of a lens array over a predetermined target region.
Claim 2
Dependent Claim
48 words
A diffractive element comprising: a computer-generated hologram comprising irregularly patterned diffractive fringes and having a phase-transmittance pattern in which a Fourier transform of the phase transmittance pattern is more uniform than a Fourier transform of a phase transmittance pattern of a lens array over a predetermined target region.
Claim 3
Dependent Claim
49 words
The diffractive element of claim 1, wherein said computer-generated hologram converts an input beam illuminating at least part of said hologram into an output beam having a preselected energy distribution including a spatial energy distribution that has a relatively uniform spatial energy magnitude and a preselected spatial energy shape.
Claim 4
Dependent Claim
36 words
The diffractive element of claim 1, wherein said computer-generated hologram converts an input beam illuminating at least part of said hologram into an output beam having a preselected energy distribution and said input beam is collimated.
Claim 5
Dependent Claim
17 words
The diffractive element of claim 1, wherein said diffractive fringes are made up of plateaus and vias.
Claim 6
Dependent Claim
23 words
The diffractive element of claim 1, wherein said phase transmittance pattern of the computer-generated hologram is relatively uniform over the predetermined target region.
Claim 7
Dependent Claim
192 words
A beam homogenizer for converting a input beam having a non-uniform spatial energy distribution into an output beam having a substantially uniform spatial energy distribution at an output plane while minimizing the intensity variation caused by breaks between facets, the beam homogenizer comprising: an array of facet areas, an input beam illuminating at least some of the facet areas, and each thusly illuminated facet transmitting a majority of the portion of the input beam incident thereupon so that at a target located at an output plane, the majority of the portion of the input beam transmitted through each of said illuminated facet areas overlaps the portion of the input beam transmitted through at least one other illuminated facet, whereby the energy of the input beam is spatially redistributed at the output plane into a homogenized output beam having a preselected spatial energy distribution at the output plane, wherein the array of facet areas is a computer generated hologram, relatively insensitive to fluctuations in positioning of the input beam for incidence thereupon and to spatial energy distributions within the input beam, and wherein said facet areas are comprised of irregularly patterned diffractive fringes.
Claim 8
Dependent Claim
192 words
A beam homogenizer for converting a input beam having a non-uniform spatial energy distribution into an output beam having a substantially uniform spatial energy distribution at an output plane while minimizing the intensity variation caused by breaks between facets, the beam homogenizer comprising: an array of facet areas, an input beam illuminating at least some of the facet areas, and each thusly illuminated facet transmitting a majority of the portion of the input beam incident thereupon so that at a target located at an output plane, the majority of the portion of the input beam transmitted through each of said illuminated facet areas overlaps the portion of the input beam transmitted through at least one other illuminated facet, whereby the energy of the input beam is spatially redistributed at the output plane into a homogenized output beam having a preselected spatial energy distribution at the output plane, wherein the array of facet areas is a computer generated hologram, relatively insensitive to fluctuations in positioning of the input beam for incidence thereupon and to spatial energy distributions within the input beam, and wherein said facet areas are comprised of irregularly patterned diffractive fringes.
Claim 9
Dependent Claim
12 words
The beam homogenizer of claim 6 wherein the input beam is collimated.
Claim 10
Dependent Claim
38 words
The beam homogenizer of claim 6 wherein the transmitted portions of the input beam overlap at target areas located at the output plane, said target areas corresponding to a preselected spatial energy distribution desired at the output plane.
Claim 11
Dependent Claim
14 words
The beam homogenizer of claim 6 wherein said diffractive fringes comprise plateaus and vias.
Claim 12
Independent Claim
175 words
A method of homogenizing an input beam having an arbitrary spatial energy distribution at a first plane into an output beam with a preselected spatial energy distribution at a second plane while minimizing the intensity variation caused by breaks between sub-holograms, the method comprising the steps of: providing a holographic optical element comprising an array of computer generated sub-holograms, said sub-holograms having irregularly patterned diffractive fringes; fixedly positioning said holographic optical element at a first plane so that the input beam illuminates at least some of the computer generated sub-holograms, each illuminated computer generated sub-hologram expansively diffracting the portion of the input beam incident thereupon over an entire target at a second plane to superimpose the diffracted portions of all of the illuminated computer generated sub-holograms to form an output beam at the second plane, wherein the step of providing the holographic element comprises generating an array of sub-holograms that is relatively insensitive to fluctuations in positioning of an input beam for incidence on said array and to spatial energy distributions within the incident beam.
Claim 13
Independent Claim
175 words
A method of homogenizing an input beam having an arbitrary spatial energy distribution at a first plane into an output beam with a preselected spatial energy distribution at a second plane while minimizing the intensity variation caused by breaks between sub-holograms, the method comprising the steps of: providing a holographic optical element comprising an array of computer generated sub-holograms, said sub-holograms having irregularly patterned diffractive fringes; fixedly positioning said holographic optical element at a first plane so that the input beam illuminates at least some of the computer generated sub-holograms, each illuminated computer generated sub-hologram expansively diffracting the portion of the input beam incident thereupon over an entire target at a second plane to superimpose the diffracted portions of all of the illuminated computer generated sub-holograms to form an output beam at the second plane, wherein the step of providing the holographic element comprises generating an array of sub-holograms that is relatively insensitive to fluctuations in positioning of an input beam for incidence on said array and to spatial energy distributions within the incident beam.
Claim 14
Dependent Claim
11 words
The method of claim 10 wherein said input beam is collimated.
Claim 15
Dependent Claim
20 words
The method of claim 11 wherein said target corresponds to a preselected spatial energy distribution desired at the output plane.
References Cited (Backward Citations)
US4170396A
Cited
US4455061A
Cited
US4410237A
Cited
US4547037A
Cited
US4682841A
Cited
US5075800A
Cited
US4979791A
Cited
US5117476A
Cited
US5061025A
Cited
US5361149A
Cited
US5657138A
Cited
US5202775A
Cited
US5383000A
Cited
US5315427A
Cited
US5289298A
Cited
US5534386A
Cited
US5610733A
Cited
FR2716726A1
Cited
US5850300A
Cited
EP0744664A2
Cited
US5631721A
Cited
US5630661A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-02-14 | 2003-08-16 | 2004-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-02-14 | 2007-08-16 | 2008-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-02-14 | 2011-08-16 | 2012-02-15 | $7700.00 | Window Closed / Lapsed |