Method to control point spread function of an image

• US 7,742,239 B2
• Filed: 03/17/2003
• Issued: 06/22/2010
• Est. Priority Date: 03/17/2002
• Status: Expired due to Term

• Current Assignee: Aptiv Technologies AG
• Original Assignee: PureDepth Limited (Aptiv PLC)
• Inventors: Evanicky, Daniel, Bell, Gareth Paul, Searle, Mark John, Engel, Gabriel Daemon
• Primary Examiner(s): Schwartz; Jordan M.
• Application Number:
  US10/508,726
• Publication Number:
  US 20060103951A1
• Time in Patent Office: 2,654 Days
• Field of Search: 359/737, 359/599, 359/609
• US Class Current: 359/737
• CPC Class Codes: G02B 27/46 Systems using spatial filters
• CPC Class Codes: G02F 1/133504 Diffusing, scattering, diffracting elements associated to illuminating devices G02F1/133606

Abstract

A method of controlling the point spread function of an image projected with said image being diffused by a filter; said point spread function is a result of the application of spatial filter(s) on said image; with said control of the point spread function effected by varying the distance between such image and said spatial filter(s) and varying the bidirectional scattering transmission function of the spatial filter(s). Said spatial filter may be a holographic diffuser, which by method of manufacture has a well defined bi-directional scattering transmission spread function. Control of said spread function is particularly useful to maintain image quality while abating moiré interference in situations where two periodic patterns are layered causing moiré interference.

Claims

1. A method of controlling a point spread function of an object, said method comprising:

determining at least one characteristic of an optical component of a multi-component display, said multi-component display further comprising a first display screen and a second display screen, wherein said first and second display screens overlap as viewed by a viewer;

determining a distance from an origin of said object to a position based upon said at least one characteristic; and

positioning said optical component at said position for controlling said point spread function of said object.

2. The method of claim 1, wherein said object comprises a displayed image.

3. The method of claim 1 further comprising:

adjusting said at least one characteristic of said optical component; and

determining an undated position for said optical component based upon a new value of said at least one characteristic.

4. The method of claim 1, wherein said origin is associated with said first display screen, and wherein said object is displayed on said first display screen.

5. The method of claim 1, wherein said determining said distance comprises determining said distance based upon a refractive index of a display screen selected from a group consisting of said first display screen and said second display screen.

6. The method of claim 1, wherein said first and second display screens are selected from a group consisting of a liquid crystal display, an organic light emitting diode display, and a transparent organic light emitting diode display.

7. The method of claim 1, wherein said at least one characteristic of said optical component is associated with optical transmission through said optical component.

8. The method of claim 1, wherein said optical component is selected from a group consisting of a spatial filter, a prismatic filter, a spatial diffuser, and a holographic diffuser.

9. The method of claim 1, wherein said positioning said optical component at said position further comprises positioning said optical component at said position for altering an optical characteristic associated with said object, and wherein said optical characteristic is selected from a group consisting of Moiré

interference and blurriness.

10. A method of controlling a point spread function of an object, said method comprising:

determining at least one characteristic of an optical component of a projection system, said projection system operable to project an image onto an image layer;

determining a distance from an origin of said object to a first position based upon said at least one characteristic; and

positioning said optical component at said first position for controlling said point spread function of said object and further wherein said position reduces Moiré

interference without over-blurring said image.

11. The method of claim 10, wherein said object comprises a projected object generated by said projection system.

12. The method of claim 10, further comprising:

adjusting said at least one characteristic of said optical component; and

re-positioning said optical component at a second position based upon a second value of said at least one characteristic.

13. The method of claim 10, wherein said at least one characteristic of said optical component is associated with optical transmission through said optical component.

14. The method of claim 10, wherein said optical component is selected from a group consisting of a spatial filter, a prismatic filter, a spatial diffuser, and a holographic diffuser.

15. A method of controlling a point spread function of an object, said method comprising:

determining at least one characteristic of an optical component of a projection system, said projection system operable to project an image onto an image layer;

determining a distance from an origin of said object to a first position based upon said at least one characteristic;

positioning said optical component at said first position for controlling said point spread function of said object;

adjusting said at least one characteristic of said optical component; and

re-positioning said optical component at a second position based upon a second value of said at least one characteristic for further controlling said point spread function of said object.

16. The method of claim 15, wherein said object comprises a projected object generated by said projection system.

17. The method of claim 15, wherein said at least one characteristic of said optical component is associated with optical transmission through said optical component.

18. The method of claim 15, wherein said optical component is selected from a group consisting of a spatial filter, a prismatic filter, a spatial diffuser, and a holographic diffuser.

19. The method of claim 15, wherein said positioning said optical component at said position further comprises positioning said optical component at said first position for altering an optical characteristic associated with said object, and wherein said optical characteristic is selected from a group consisting of Moiré

interference and blurriness of said object.