Near real-time holographic display for remote operations

• US 5,227,898 A
• Filed: 12/02/1991
• Issued: 07/13/1993
• Est. Priority Date: 12/02/1991
• Status: Expired due to Term

• Current Assignee: Comp Sci Holdings LLC (Intellectual Ventures LLC)
• Original Assignee: Computer Sciences Corporation (DXC Technology Company)
• Inventors: Rhodes, William T., Iavecchia, Helene P., Huff, Lloyd
• Primary Examiner(s): Arnold, Bruce Y.
• Assistant Examiner(s): RYAN, JAY
• Application Number:
  US07/801,791
• Time in Patent Office: 589 Days
• Field of Search: 359/1, 359/9, 359/11, 358/90
• US Class Current: 359/9
• CPC Class Codes: G03H 1/28 superimposed holograms only
• CPC Class Codes: G03H 2001/2655 Time multiplexing, i.e. consecutive records wherein the period between records is pertinent per se
• 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 2210/454 into planes
• CPC Class Codes: G03H 2210/46 for subsequent optical processing G03H1/268 takes precedence
• CPC Class Codes: G03H 2260/12 Photopolymer

Abstract

A near-real-time holographic display for operations at a remote work site where a three dimensional database is collected with a laser range scanner. The database is then divided into discrete two dimensional segments or depth planes. A holographic recording material is then sequentially exposed to multiple depth planes through a stack of three spatial light modulators in a multiplane exposure process. This procedure is repeated for all depth planes in the database. The holographic recording material is then rapidly developed for viewing of the remote work site in a holographic image that simulates natural vision.

Claims

1. A method of presenting a holographic display of a remote work site comprising;

creating a database of three dimensional surface points of said remote work site;

dividing said database into a plurality of two dimensional depth planes;

exposing a near-real-time holographic recording material with each of said two dimensional depth planes;

developing said holographic recording material to produce a full-parallax three-dimensional image of said remote work site;

viewing said full-parallax three-dimensional image;

whereby a near-real-time hologram image simulating natural vision is provided for remote manipulation of an object.

2. The method according to claim 1 in which said database is created by;

scanning said remote work site with a laser range scanner;

collecting the three dimensional surface points of said remote work site.

3. The method according to claim 2 in which said plurality of depth planes said database is divided into is between 20 and 80.

4. The method according to claim 2 in which said database is divided into depth planes of approximately 3 mm depth separation.

5. The method according to claim 1 in which said holographic recording material is exposed through one or more spatial light modulators.

6. The method according to claim 5 in which said holographic recording material is exposed through a plurality of spatial light modulators arranged in a stack.

7. The method according to claim 6 in which said holographic recording material is exposed through a stack of three spatial light modulators.

8. The method according to claim 7 in which said holographic material is exposed simultaneously with groups of two dimensional depth planes.

9. The method according to claim 8 in which said holographic material is sequentially exposed simultaneously with said groups of two dimensional depth planes until all depth planes have been used.

10. The method according to claim 9 in which said holographic recording material is exposed through a stack of spatial light modulators mounted on a micropositioning table;

said stack of spatial light modulators being repositioned after each multiple exposure.

11. The method according to claim 6 in which said developed holographic image is viewed by replacing said stack of spatial light modulators with a mirror.

12. The method according to claim 1 in which said holographic material is a thermoplastic holographic recording material.

13. The method according to claim 1 in which said holographic material is a photopolymer holographic material.

14. The method according to claim 13 in which said photopolymer holographic recording material is developed by illuminating the holographic recording material with ultraviolet light.

15. A system for presenting a holographic display of a remote work site in near-real-time comprising;

database creating means for creating a three dimensional database of a remote worksite;

dividing means dividing said database in a plurality of two dimensional depth planes;

holographic recording means;

exposing means for exposing said holographic recording means to said plurality of two dimensional depth planes;

developing means for developing said holographic recording means to produce a holographic image of said remote work site;

viewing means for viewing said holographic image;

whereby a near-real-time holographic image of said remote work site may be viewed for remote manipulation of an object.

16. The system according to claim 15 in which said database creating means comprises;

laser range scanning means for scanning said remote work site to collect three dimensional numerical data representing said remote work site.

17. The system according to claim 16 in which said laser range scanner is mounted on a micropositioning table for scanning said remote work site and sequentially repositioning said micropositioning table to move said laser range scanner after each scan.

18. The system according to claim 15 in which said exposing means comprises one or more spatial light modulators;

one or more of said two dimensional depth planes being applied to said one or more spatial light modulators;

whereby said one or more spatial light modulators act as a holographic object source.

19. The system according to claim 18 in which said one or more spatial light modulators is three spatial modulators in abutting relationship forming a stack.

20. The system according to claim 19 in which said two dimensional depth planes are sequentially applied in groups of three, one each to each spatial light modulator in said stack until said holographic recording material has been exposed to all two dimensional depth planes.

21. The system according to claim 19 including a micropositioning table;

said stack of three spatial light modulators being mounted on said micropositioning table for repositioning after being exposed to each group of two dimensional depth planes.

22. The system according to claim 15 in which said holographic recording material is a thermoplastic holographic recording material.

23. The system according to claim 15 in which said holographic recording material is a photopolymer holographic recording material.

24. The system according to claim 23 in which said photopolymer recording material is developed by illuminating the photopolymer holographic recording material with ultraviolet light.

25. The system according to claim 15 in which said database is divided into segments that provide two dimensional depth planes representing approximately 3 mm in depth.

26. The system according to claim 15 in which said database is divided into segments that provide between 20 and 80 two dimensional depth planes.

27. The system according to claim 15 in which said developed holographic image is viewed by replacing said means for exposing said holographic recording material with a mirror.

28. The system according to claim 15 in which said laser range scanner is mounted on a micropositioning table for repositioning after each scan.