Holographic printer

• US 7,324,248 B2
• Filed: 11/02/2005
• Issued: 01/29/2008
• Est. Priority Date: 12/10/1999
• Status: Expired due to Fees

• Current Assignee: XYZ Imaging, Inc.
• Original Assignee: XYZ Imaging, Inc.
• Inventors: Vergnes, Florian Michel Robert, Brotherton-Ratcliffe, David, Rodin, Alexey, Grichine, Mikhail
• Primary Examiner(s): AMARI, ALESSANDRO V
• Application Number:
  US11/265,473
• Publication Number:
  US 20070030544A1
• Time in Patent Office: 818 Days
• Field of Search: 359/9, 359/22, 359/23, 359/24, 359/25, 359/35
• US Class Current: 359/22
• CPC Class Codes: G03H 1/0891 Processes or apparatus adapted to convert digital holographic data into a hologram G03H1/2294 takes precedence
• CPC Class Codes: G03H 1/16 using Fourier transform G03H1/10, G03H1/12, G03H1/14 take precedence; analogue computers G06G, e.g. G06G7/19
• CPC Class Codes: G03H 1/24 using white light , e.g. rainbow holograms
• CPC Class Codes: G03H 1/268 Holographic stereogram
• CPC Class Codes: G03H 2001/0216 Optical components G03H2001/0224, G03H1/0256 take precedence; corresponding details, see subgroups of G03H2223/00
• CPC Class Codes: G03H 2001/0413 for recording transmission holograms
• CPC Class Codes: G03H 2001/0415 for recording reflection holograms
• CPC Class Codes: G03H 2001/0428 Image holography, i.e. an image of the object or holobject is recorded G03H1/0406 takes precedence; holographic microscope G03H2001/005
• CPC Class Codes: G03H 2001/0473 Particular illumination angle between object or reference beams and hologram
• CPC Class Codes: G03H 2001/2263 Multicoloured holobject
• CPC Class Codes: G03H 2001/2265 Achromatic holobject
• CPC Class Codes: G03H 2001/2268 Rainbow hologram
• CPC Class Codes: G03H 2001/2273 Pseudo-dynamic holobject, e.g. due to angle multiplexing and viewer motion
• CPC Class Codes: G03H 2001/2685 One step recording process
• CPC Class Codes: G03H 2001/269 Two and more than two steps recording process
• CPC Class Codes: G03H 2001/2695 Dedicated printer holographic printers G03H1/0476
• CPC Class Codes: G03H 2001/306 Tiled identical sub-holograms
• CPC Class Codes: G03H 2210/22 2D SLM object wherein the object beam is formed of the light modulated by the SLM SLM per se G03H2001/0224
• CPC Class Codes: G03H 2210/40 Synthetic representation, i.e. digital or optical object decomposition
• CPC Class Codes: G03H 2210/42 from real object, e.g. using 3D scanner
• CPC Class Codes: G03H 2210/441 : Numerical processing applied to the object data other than numerical propagation synthesizing propagation G03H1/0808
• CPC Class Codes: G03H 2210/454 : into planes
• CPC Class Codes: G03H 2222/22 : Spatial coherence
• CPC Class Codes: G03H 2222/33 : Pulsed light beam
• CPC Class Codes: G03H 2222/50 : Geometrical property of the irradiating beam
• CPC Class Codes: G03H 2223/19 : Microoptic array, e.g. lens array

Abstract

A method and apparatus for producing holograms may use a computer generated 3-D model or data generated using multiple 2-D camera images taken of a real 3-D object or scene. The data is digitally processed and displayed on a high resolution spatial light modulator (SLM). A low energy pulsed laser records composite holograms on a holographic emulsion using a special optical design. Restricted or full parallax master transmission or reflection type composite holograms, known as H1 holograms, may be created that can be copied using traditional methods to produce full or single color rainbow white-light transmission holograms, achromatic white-light transmission holograms or single or full-color white-light reflection holograms. Alternatively, full or single color rainbow white-light transmission composite holograms, achromatic white-light transmission composite holograms or single or full-color white-light reflection composite holograms may be directly written without passing through the intermediate stage of the H1 transmission hologram.

Claims

1. A holographic printer for directly writing 1-step white-light viewable holograms, comprising:

a pulsed laser source arranged to produce a laser beam at a first wavelength, said laser beam being split into an object beam and a reference beam which is mutually coherent with said object beam;

a spatial light modulator wherein, in use, said object beam illuminates said spatial light modulator;

a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator; and

automatic spatial coherence varying means for automatically varying the spatial coherence of said object beam so as to control the diameter of said object beam at the Fourier plane of said lens system.

2. The holographic printer of claim 1, wherein said automatic spatial coherence varying means is arranged upstream of said spatial light modulator.

3. The holographic printer of claim 1, wherein said spatial light modulator is translatable.

4. The holographic printer of claim 1, wherein said automatic spatial coherence varying means comprises an adjustable telescope and a microlens array.

5. The holographic printer of claim 4, wherein said adjustable telescope is arranged to create an approximately collimated variable diameter laser beam that illuminates said microlens array.

6. The holographic printer of claim 5, wherein said adjustable telescope may be adjusted so as to vary the diameter of the object beam at the Fourier plane.

7. The holographic printer of claim 1, further comprising means for modifying images sent to said spatial light modulator so as to at least partially correct for inherent optical distortions of said lens system.

8. The holographic printer of claim 1, wherein said lens system has an effective field of view selected from the group consisting of:

(i) greater than 70 degrees;

(ii) greater than 75 degrees;

(iii) greater than 80 degrees; and

(iv) at least 85 degrees.

9. The holographic printer of claim 1, wherein the Fourier plane of said lens system is located downstream of said lens system.

10. The holographic printer of claim 9, wherein the Fourier plane of said lens system is located at least 2 mm downstream of said lens system.

11. The holographic printer of claim 1, wherein said laser source is arranged to additionally produce laser beams at second and third wavelengths.

12. The holographic printer of claim 11, wherein said first, second and third wavelengths each differ from one another by at least 30 nm.

13. The holographic printer of claim 1, further comprising a second pulsed laser source for producing a laser beam at a second wavelength.

14. The holographic printer of claim 13, further comprising a second lens system for use at said second wavelength.

15. The holographic printer of claim 14, further comprising a third pulsed laser source for producing a laser beam at a third wavelength.

16. The holographic printer of claim 15, further comprising a third lens system for use at said third wavelength.

17. The holographic printer of claim 16, wherein said first, second and third wavelengths each differ from one another by at least 30 nm.

18. A method of directly writing 1-step white-light viewable holograms, comprising:

providing a pulsed laser source arranged to produce a laser beam at a first wavelength;

splitting said laser beam into an object beam and a reference beam which is mutually coherent with said object beam;

illuminating a spatial light modulator with said object beam;

providing a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator; and

automatically varying the spatial coherence of said object beam so as to control the diameter of said object beam at the Fourier plane of said lens system.

19. A holographic printer for directly writing 1-step white-light viewable holograms, comprising:

a pulsed laser source arranged to produce a laser beam at a first wavelength, said laser beam being split into an object beam and a reference beam which is mutually coherent with said object beam;

a spatial light modulator wherein, in use, said object beam illuminates said spatial light modulator;

a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator; and

a positioning stage for positioning a photosensitive medium at the Fourier plane of said lens system.

20. The holographic printer of claim 19, wherein said spatial light modulator is translatable.

21. The holographic printer of claim 19, wherein the Fourier plane of said lens system is located downstream of said lens system.

22. The holographic printer of claim 21, wherein the Fourier plane of said lens system is located at least 2 mm downstream of said lens system.

23. The holographic printer of claim 19, wherein said laser source is arranged to additionally produce laser beams at second and third wavelengths.

24. The holographic printer of claim 23, wherein said first, second and third wavelengths each differ from one another by at least 30 nm.

25. The holographic printer of claim 19, further comprising a second pulsed laser source for producing a laser beam at a second wavelength.

26. The holographic printer of claim 25, further comprising a second lens system for use at said second wavelength.

27. The holographic printer of claim 26, further comprising a third pulsed laser source for producing a laser beam at a third wavelength.

28. The holographic printer of claim 27, further comprising a third lens system for use at said third wavelength.

29. The holographic printer of claim 28, wherein said first, second and third wavelengths each differ from one another by at least 30 nm.

30. A method of directly writing 1-step white-light viewable holograms, comprising:

providing a pulsed laser source arranged to produce a laser beam at a first wavelength;

splitting said laser beam into an object beam and a reference beam which is mutually coherent with said object beam;

illuminating a spatial light modulator with said object beam;

providing a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator; and

positioning a photosensitive medium at the Fourier plane of said lens system.

31. A holographic printer for directly writing 1-step white-light viewable holograms, comprising:

a pulsed laser source arranged to produce a laser beam at a first wavelength, said laser beam being split into an object beam and a reference beam which is mutually coherent with said object beam;

a spatial light modulator wherein, in use, said object beam illuminates said spatial light modulator;

a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator, wherein said lens system has an effective field of view selected from the group consisting of;

(i) greater than 70 degrees;

(ii) greater than 75 degrees;

(iii) greater than 80 degrees; and

(iv) at least 85 degrees; and

a positioning stage for positioning a photosensitive medium at the Fourier plane of said lens system.

32. A method of directly writing 1-step white-light viewable holograms, comprising:

providing a pulsed laser source arranged to produce a laser beam at a first wavelength;

splitting said laser beam into an object beam and a reference beam which is mutually coherent with said object beam;

illuminating a spatial light modulator with said object beam;

providing a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator, wherein said lens system has an effective field of view selected from the group consisting of;

(i) greater than 70 degrees;

(ii) greater than 75 degrees;

(iii) greater than 80 degrees; and

(iv) at least 85 degrees; and

positioning a photosensitive medium at the Fourier plane of said lens system.

33. A holographic printer for directly writing 1-step white-light viewable holograms, comprising:

a pulsed laser source arranged to produce a laser beam at a first wavelength, said laser beam being split into an object beam and a reference beam which is mutually coherent with said object beam;

a spatial light modulator wherein, in use, said object beam illuminates said spatial light modulator;

a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator, wherein said lens system has an effective field of view selected from the group consisting of;

(i) greater than 70 degrees;

(ii) greater than 75 degrees;

(iii) greater than 80 degrees; and

(iv) at least 85 degrees; and

means for modifying images sent to said spatial light modulator so as to at least partially correct for inherent optical distortions of said lens system.

34. A method of directly writing 1-step white-light viewable holograms, comprising:

providing a pulsed laser source arranged to produce a laser beam at a first wavelength;

splitting said laser beam into an object beam and a reference beam which is mutually coherent with said object beam;

illuminating a spatial light modulator with said object beam;

providing a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator, wherein said lens system has an effective field of view selected from the group consisting of;

(i) greater than 70 degrees;

(ii) greater than 75 degrees;

(iii) greater than 80 degrees; and

(iv) at least 85 degrees; and

modifying images sent to said spatial light modulator so as to at least partially correct for inherent optical distortions of said lens system.

35. A holographic printer for directly writing 1-step white-light viewable holograms, comprising:

a pulsed laser source arranged to produce a laser beam at a first wavelength, said laser beam being split into an object beam and a reference beam which is mutually coherent with said object beam;

a spatial light modulator wherein, in use, said object beam illuminates said spatial light modulator;

a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator;

means for modifying images sent to said spatial light modulator so as to at least partially correct for inherent optical distortions of said lens system; and

a positioning stage for positioning a photosensitive medium at the Fourier plane of said lens system.

36. A method of directly writing 1-step white-light viewable holograms, comprising:

providing a pulsed laser source arranged to produce a laser beam at a first wavelength;

splitting said laser beam into an object beam and a reference beam which is mutually coherent with said object beam;

illuminating a spatial light modulator with said object beam;

providing a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator;

modifying images sent to said spatial light modulator so as to at least partially correct for inherent optical distortions of said lens system; and

positioning a photosensitive medium at the Fourier plane of said lens system.

37. A holographic printer for directly writing 1-step white-light viewable holograms, comprising:

a pulsed laser source arranged to produce a laser beam at a first wavelength, said laser beam being split into an object beam and a reference beam which is mutually coherent with said object beam;

a spatial light modulator wherein, in use, said object beam illuminates said spatial light modulator;

a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator, wherein said lens system has an effective field of view selected from the group consisting of;

(i) greater than 70 degrees;

(ii) greater than 75 degrees;

(iii) greater than 80 degrees; and

(iv) at least 85 degrees.

38. A method of directly writing 1-step white-light viewable holograms, comprising:

providing a pulsed laser source arranged to produce a laser beam at a first wavelength;

splitting said laser beam into an object beam and a reference beam which is mutually coherent with said object beam;

illuminating a spatial light modulator with said object beam; and

providing a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator, wherein said lens system has an effective field of view selected from the group consisting of;

(i) greater than 70 degrees;

(ii) greater than 75 degrees;

(iii) greater than 80 degrees; and

(iv) at least 85 degrees.

39. A holographic printer for directly writing 1-step white-light viewable holograms, comprising:

a pulsed laser source arranged to produce a laser beam at a first wavelength, said laser beam being split into an object beam and a reference beam which is mutually coherent with said object beam;

a spatial light modulator wherein, in use, said object beam illuminates said spatial light modulator;

a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator; and

means for modifying images sent to said spatial light modulator so as to at least partially correct for inherent optical distortions of said lens system.

40. A method of directly writing 1-step white-light viewable holograms, comprising:

providing a pulsed laser source arranged to produce a laser beam at a first wavelength;

splitting said laser beam into an object beam and a reference beam which is mutually coherent with said object beam;

illuminating a spatial light modulator with said object beam;

providing a lens system for writing a holographic pixel of a hologram on to a photosensitive medium, said lens system being arranged downstream of said spatial light modulator; and

modifying images sent to said spatial light modulator so as to at least partially correct for inherent optical distortions of said lens system.