Pass-through reflective projection display

• US 5,639,151 A
• Filed: 02/16/1996
• Issued: 06/17/1997
• Est. Priority Date: 02/16/1996
• Status: Expired due to Term

• Current Assignee: Videotronic Systems
• Original Assignee: Videotronic Systems
• Inventors: McNelley, Steve H., Machtig, Jeffrey S.
• Primary Examiner(s): DOWLING, WILLIAM C
• Application Number:
  US08/602,336
• Time in Patent Office: 487 Days
• Field of Search: 353/72, 353/73, 353/74, 353/75, 353/77, 353/78, 353/98, 353/99, 353/119, 353/122, 353/28, 353/10, 359/629, 359/630, 359/636, 359/631, 379/52, 379/202, 348/14, 348/15, 348/20
• US Class Current: 353/98
• CPC Class Codes: G03B 15/10 using back-projection, i.e. blending artificial background with real foreground
• CPC Class Codes: G03B 17/54 with projector
• CPC Class Codes: G03B 21/10 Projectors with built-in or built-on screen
• CPC Class Codes: G03B 21/28 Reflectors in projection beam in illumination beam G03B21/2066
• CPC Class Codes: H04N 5/642 Disposition of sound reproducers
• CPC Class Codes: H04N 7/144 camera and display on the same optical axis, e.g. optically multiplexing the camera and display for eye to eye contact
• CPC Class Codes: H04N 9/3141 Constructional details thereof details not peculiar to the presence of an electronic spatial light modulator G03B21/14

Abstract

An improved desktop projection display system which effectively utilizes desk top space by producing an image that appears to be at the rear edge of the desk. The display is compact because it uses a transparent-reflective panel (i.e., beamsplitter) to reflect a screen image through the same space occupied by the projection beam. This is achieved by projecting through a transparent-reflective panel, angled at approximately 45 degrees to the projection beam, onto a front projection screen located on the desk surface. An image formed on the front projection screen is then reflected by the transparent-reflective panel creating the appearance to the observer that the reflected front projection screen is positioned toward the rear of the desk surface. This invention greatly improves desktop display ergonomics for large display viewing by providing a sufficient distance between the observer seated at a desk and the display image. It is also possible to position a camera behind the transparent-reflective panel at the apparent position of the reflected screen image thus ensuring teleconferencing eye contact. The present invention, though ideal for desk top use, may also be incorporated into devices such as laptop computers or configured in kiosks or used in a manner similar to big screen projection televisions.

Claims

1. A pass-through reflective projection display system comprising:

projector means for projecting an image beam;

a front projection image screen for making the image beam visible as an image; and

a transparent-reflective panel disposed so the image beam from the projector means strikes the transparent-reflective panel and is transmitted therethrough to reach the front projection image screen forming a visible image, the transparent-reflective panel angled relative to the front projection image screen for reflecting the visible image formed thereon so that an observer gazing toward a front projection image screen-facing side of the panel will perceive a reflection of the visible image as appearing at a distance beyond the transparent-reflective panel.

2. The display system as defined in claim 1 further comprising a speaker for sound reproduction wherein the speaker is disposed on a side of the transparent-reflective panel from which the observer views the image and wherein the speaker is aimed towards the transparent-reflective panel so that sound produced by the speaker is reflected by the panel and seems to emanate from the reflection of the image.

3. The display system as defined in claim 1, wherein the front projection image screen is formed with three-dimensional relief.

4. The display system as defined in claim 1, wherein the transparent-reflective panel is bowed so as to alter proportions of the reflection of the front projection image screen.

5. The display system as defined in claim 1, wherein apparent contrast of the reflection is enhanced by providing a light absorbing background against which the observer views the reflection the background disposed on a side of the transparent-reflective panel opposite the observer.

6. The display system as defined in claim 1, wherein a directional image blocker is disposed between the front projection image screen and the transparent-reflective panel to obscure the image on the front projection image screen when the observer looks directly at the front projection image screen.

7. The display system as defined in claim 1, wherein a first polarizer is disposed between the front projection image screen and the transparent-reflective panel and a second polarizer is disposed between the observer and the transparent-reflective panel to obscure the image on the front projection image screen when the observer looks directly at the front projection image screen.

8. The display system as defined in claim 1 further comprising a camera disposed on a side of the transparent-reflective panel opposite the observer for obtaining an image of the observer.

9. The display system as defined in claim 1 further comprising a substantially opaque housing, the housing being substantially open along a surface thereof to allow the observer to view the front projection image screen-facing surface of the panel.

10. The display system as defined in claim 9, wherein the housing further comprises means for collapsing the housing into a compact unit for transporting the display system.

11. The display system as defined in claim 9, wherein the projector means comprises a projector removably mounted within the housing and wherein the housing further comprises means for removing the projector for use independent of the display system.

12. The display system as defined in claim 9 further comprising a camera disposed on a side of the transparent-reflective panel opposite the observer for obtaining an image of the observer, wherein the camera is removably disposed within the housing and wherein the housing further comprises means for removing the camera for use independent of the display system.

13. A pass-through reflective projection display system with a video conferencing eye contact feature comprising:

projector means for projecting an image beam;

a front projection image screen for making the image beam visible as an image;

a transparent-reflective panel disposed so the image beam from the projector means strikes the transparent-reflective panel and is transmitted therethrough to reach the front projection image screen forming a visible image thereon, the transparent-reflective panel angled relative to the front projection image screen for reflecting the visible image so that an observer gazing toward a front projection image screen-facing side of the panel will perceive a reflection of the visible image as appearing at a distance beyond the transparent-reflective panel; and

a camera disposed on a side of the transparent-reflective panel opposite the observer for obtaining an image of the observer.

14. The display system as defined in claim 13 further comprising a speaker for sound reproduction wherein the speaker is disposed on a side of the transparent-reflective panel from which the observer views the image and wherein the speaker is aimed towards the transparent-reflective panel so that sound produced by the speaker is reflected by the panel and seems to emanate from the reflection.

15. The display system as defined in claim 13, wherein the front projection image screen is formed with three-dimensional relief.

16. The display system as defined in claim 13, wherein the transparent-reflective panel is bowed so as to alter proportions of the reflection of the front projection image screen.

17. The display system as defined in claim 13, wherein apparent contrast of the reflection is enhanced by providing a light absorbing surface against which the observer views the reflection, the background disposed on the side of the transparent reflective panel opposite the observer.

18. The display system as defined in claim 13, wherein a directional image blocker is disposed between the front projection image screen and the transparent-reflective panel to obscure the image on the front projection image screen when the observer looks directly at the front projection image screen.

19. The display system as defined in claim 13, wherein a first polarizer is disposed between the front projection image screen and the transparent-reflective panel and a second polarizer is disposed between the observer and the transparent-reflective panel to obscure the image on the front projection image screen when the observer looks directly at the front projection image screen.

20. The display system as defined in claim 13 further comprising a substantially opaque housing, the housing being substantially open along a surface thereof to allow the observer to view the front projection image screen-facing surface of the panel.

21. The display system as defined in claim 20, wherein the housing further comprises means for collapsing the housing into a compact unit for transporting the display system.

22. The display system as defined in claim 20, wherein the projector means comprises a projector removably mounted within the housing and wherein the housing further comprises means for removing the projector for use independent of the display system.

23. The display system as defined in claim 20, wherein the camera is removably disposed within the housing and wherein the housing further comprises means for removing the camera for use independent of the display system.

24. A reflected image projection display system comprising:

projector means for projecting an image beam;

a screen for making the image beam visible as an image, the screen having three-dimensional relief for modifying the visible image; and

a transparent-reflective panel disposed so the image beam from the projector means strikes the transparent-reflective panel and is transmitted therethrough to reach the screen forming a visible image, the transparent-reflective panel angled relative to the image beam for reflecting the visible image so that an observer gazing toward a screen-facing surface of the panel will perceive the visible image as appearing at a distance beyond the transparent-reflective panel.

25. The image projection display system of claim 24 further comprising a camera disposed on a side of the transparent-reflective panel opposite that facing the observer for obtaining an image of the observer viewing the display.

26. A reflected image projection display system comprising:

projector means for projecting an image beam;

a screen for making the image beam visible as an image;

a transparent-reflective panel disposed so the image beam from the projector means strikes the transparent-reflective panel and is transmitted therethrough to reach the screen forming a visible image, the transparent-reflective panel angled relative to the image beam for reflecting the visible image so that an observer gazing toward a screen-facing surface of the panel will perceive the visible image as appearing at a distance beyond the transparent-reflective panel; and

image blocking means to obscure the image on the screen when the observer looks directly at the screen.

27. The image display of claim 26, wherein the image blocking means is provided by a directional image blocking film disposed between the transparent-reflective panel and the screen.

28. The image display of claim 26, wherein the image blocking means is provided by a first polarizer disposed between the transparent-reflective panel and the screen and a second polarizer disposed between the observer and the transparent-reflective panel.

29. The image display of claim 26, wherein the image blocking means is provided by angling the screen away from the observer.

30. The image display system of claim 26 further comprising a camera disposed on a side of the transparent-reflective panel opposite that facing the observer for obtaining an image of the observer viewing the display.

31. The display system as defined in claim 26, wherein an adjustable ledge shields the screen from direct view.