3-D imaging system

• US 20030146883A1
• Filed: 02/14/2001
• Published: 08/07/2003
• Est. Priority Date: 08/28/1997
• Status: Abandoned Application

• Current Assignee: Visualabs, Inc.
• Original Assignee: Visualabs, Inc.
• Inventors: Zelitt, Sheldon S.
• Application Number:
  US09/781,968
• Publication Number:
  US 20030146883A1
• Time in Patent Office: Days
• US Class Current: 345/6
• CPC Class Codes: G09G 3/003 to produce spatial visual effects
• CPC Class Codes: H04N 13/122 Improving the 3D impression of stereoscopic images by modifying image signal contents, e.g. by filtering or adding monoscopic depth cues H04N13/128 takes precedence
• CPC Class Codes: H04N 13/194 Transmission of image signals
• CPC Class Codes: H04N 13/305 using lenticular lenses, e.g. arrangements of cylindrical lenses
• CPC Class Codes: H04N 13/322 using varifocal lenses or mirrors

Abstract

The invention relates to a method of converting conventional 2-D imaging to 3-D imaging, by digitizing each scene to be converted, defining individual objects within the scene, assigning a specified depth to each object in the scene, scanning each pixel in the scene and assigning respective depth components to the pixels according to the specified depth.

Claims

1. A 2-dimensional display device on which an image formed by discrete pixels is presented, the display device having an array of optical elements aligned respectively in front of the pixels and means for individually varying the effective focal length of each optical element to vary the apparent visual distance from a viewer, positioned in front of the display device, at which each individual pixel appears, whereby a 3-dimensional image is created, characterized in that each optical element (2) has a focal length which varies progressively along surfaces oriented generally parallel to the image, and characterized by means (18, 65) for displacing minutely within a pixel the location (5b, 6b, 7b) at which light is emitted according to a desired depth such that there is a corresponding displacement of an input location (5, 6, 7) of the light along an input surface of the optical element whereby the effective focal length is dynamically varied and the apparent visual distance (5a, 6a, 7a) from the viewer varies according to the displacement of the input location of light.

2. A display device as claimed in claim 1 characterized in that the optical elements (2) are refractory elements and the input surface is a refractory surface.

3. A display device as claimed in claim 2 characterized in that the refractory surfaces are shaped to provide the varying focal length.

4. A display device as claimed in claim 2 characterized in that the optical refractory elements (2) are each made of gradient index optical materials in which the index of refraction varies progressively along the refractory element to produce the varying focal length.

5. A display device as claimed in claim 2, 3 or 4 characterized in that the relationship between the displacement and the focal length is linear.

6. A display device as claimed in claim 2, 3 or 4 characterized in that the relationship between the displacement and the focal length is non-linear.

7. A display device as claimed in any of claims 2 to 6 characterized in that each optical refractory element (39) has a focal length which varies radially with respect to an optical axis of the optical refractory element, and the displacing means displaces radially within a pixel the location (40a, 41a, 42a) at which light is emitted.

8. A display device as claimed in any of claims 2 to 6 characterized in that each optical refractory element (2) is elongate and has a focal length which varies along its length from one end, and the display means displaces linearly within a pixel the point at which light is emitted.

9. A display device as claimed in any preceding claim characterized in that the display device includes one of a liquid crystal display device, electroluminescence device and plasma display device as a light source.

10. A display device as claimed in claim 8 characterized in that the display device includes a cathode ray tube (10) having thereon a plurality of elongate phosphor pixels and in that the means for displacing linearly within a pixels the location at which light is emitted comprises means (65) for displacing the electron beam along each phosphor pixel.

11. A display device as claimed in claim 10 characterized in that the electron beam is rectangular (66d) in cross-section.

12. A display device as claimed in claim 10 characterized in that the electron beam is oval (66c) in cross section.

13. A display device as claimed in claim 10, 11 or 12 characterized in that the pixels are arranged in rows and characterized in that the display device is a television receiver having means (58, 59, 61, 62, 63) for extracting a depth component for each pixel from a received signal and means (60) for adding the depth component to the conventional horizontal scan line to control the vertical level of the horizontal scan line pixel by pixel whereby a stepped raster scan line (20) is obtained.

14. A display device as claimed in claim 2 characterized in that a minute interstitial gap is provided between the individual optical elements.

15. A display device as claimed in claim 14 characterized in that a black opaque material fills the interstitial gap.

16. A display device as claimed in claim 2 characterized in that the optical elements are provided as an embossed sheet of plastics material.

17. A display device as claimed in claim 2 characterized in that the optical elements are provided on a sheet of injection moulded plastics material.

18. A display device as claimed in claim 2 characterized in that each optical element is a compound device comprising at least two individual optical components (FIG. 1(b)).

19. A display device as claimed in claim 18 characterized in that the at least two individual optical components are provided as at least two embossed sheets of plastics material which are cemented together.

20. A display device as claimed in claim 18 characterized in that the at least two individual optical components are provided as at least two embossed sheets of plastics material which are secured together at their edges.

21. A display device as claimed in claim 8 characterized in that the display device is a viewer or projector for a photographic film transparency (14) and the means for displacing the point at which light is emitted comprises a mask applied to each pixel of the transparency such that a preselected transparent point (5c) is provided.

27. A display device as claimed in claim 1 characterized in that the optical elements are mirrors (76, 77) and the input surface is a reflecting surface.

28. A display device as claimed in claim 27 characterized in that each optical element comprises a plane mirror (76) and a concave mirror (77).

29. A display device as claimed in claim 28 characterized in that each plane mirror (76) is formed as one surface of a combined element (78) another surface of which forms a concave mirror (77) of an adjacent pixel.

30. A display device as claimed in claim 10, 11 or 12 characterized in that the display device is a computer monitor and computer based video driver electronics having means for extracting a depth component for each pixel from data received from a computer and means (19) for adding the depth component to the conventional horizontal scan line pixel by pixel whereby a stepped raster (20) is obtained.

22. A method of forming a 3-dimensional image from a 2-dimensional image display formed by discrete pixels comprising providing an array of optical elements respectively in alignment in front of the pixels and varying the effective focal length of each optical element to vary the apparent visual distance from a viewer positioned in front of the display at which each individual pixel appears, characterized in that each optical element has a focal length which varies progressively along surfaces oriented generally parallel to the image and in that varying the effective focal length of each optical element comprises the steps of displacing immediately within each pixel the location at which light is emitted from the 2-dimensional image, and passing the emitted light to optical elements, the location at which the emitted light impinges upon the optical elements determining the apparent depth of the pixel.

23. A method according to claim 22 characterized in that the optical elements are refractory elements and the light enters a refractory surface of the associated refractory element.

24. A method according to claim 22 characterized in that the optical elements are mirrors and the light engages a reflecting surface of the associated mirror.

25. A method according to claim 22, 23 or 24 characterized in that the step of displacing the location at which light is emitted from the 2-dimensional image, comprises displacing the point linearly at which light is emitted from the 2-dimensional image.

26. A method according to claim 22, 23 or 24 characterized in that the step of displaying the location at which light is emitted from the 2-dimensional image comprises displacing the location radially at which light is emitted from the 2-dimensional image.

31. A printed or photographic 2-dimensional image formed by discrete pixels and an array or microlenses aligned respectively with the pixels and applied to the 2-dimensional image, each microlens having a respective fixed focal length chosen to portray the associated pixel at a predetermined distance from the viewer.

32. A method of encoding a television broadcast signal comprising the steps of generating a depth signal for each pixel and adding the depth signal as a component of the broadcast signal.

33. A method of decoding a television broadcast signal encoded according to claim 32 comprising the step of extracting the depth signal component.

34. A method of encoding a television broadcast signal as claimed in claim 32 in which the step of generating the depth signal comprises a triangulation technique using two spaced cameras.

35. A method of encoding a television broadcast signal as claimed in claim 32 in which the step of generating the depth signal comprises the use of non-optical depth sensors.

36. A method of retrofitting 3-D information to conventional 2-D imaging, comprising the steps of digitizing each scene, defining individual objects in the scene, assigning a specified depth to each object in the scene, scanning each pixel in the scene and assigning respective depth components to the pixels according to the specified depth.