US5400069A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Eye contact video-conferencing system and screen
Assignee: University of California
•
Filing: 1993-06-16
•
Granted: 1995-03-21
•
Expires: 2013-06-16
Abstract
Abstract Our video-conferencing system comprises stations which are remotely located from one another and interconnected by a transmission system. Each station includes a camera, a projector, and a screen, which is simultaneously translucent with respect to the projector and transparent with respect to the camera. The projector as well as the camera are placed behind and in line with the screen, thus allowing greater viewing reciprocity and eye-contact and projecting a stronger feeling of reality to the video-conferencing parties. Our screen includes segments which discriminates between projected light and light to be captured by the camera based upon polarization or angle.
Inventors
- 👤 David A. Braun
- 👤 Terence J. Nelson
- 👤 Lanny S. Smoot
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:31
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/14; H04N7/141; H04N7/142; H04N7/144
Claims Analysis
Total Claims: 43
Claim 1
Independent Claim
62 words
A video-conferencing system comprising a plurality of stations interconnected by a transmission system, each station including a screen for displaying images, said screen being simultaneously transparent and translucent; a camera located behind said screen for generating a video signal of images captured through said screen; and a projector for projecting images, said projected images being diffused at, and displayed on, said screen.
Claim 2
Dependent Claim
62 words
A video-conferencing system comprising a plurality of stations interconnected by a transmission system, each station including a screen for displaying images, said screen being simultaneously transparent and translucent; a camera located behind said screen for generating a video signal of images captured through said screen; and a projector for projecting images, said projected images being diffused at, and displayed on, said screen.
Claim 3
Dependent Claim
72 words
A video-conferencing system comprising a plurality of stations interconnected by a transmission system, each station including a screen for displaying images, said screen being simultaneously transparent and translucent; a camera located behind said screen for generating a video signal of images captured through said screen; a projector for displaying projected images on said screen, and means located between said camera and said screen for blocking said projected images from entering said camera.
Claim 4
Dependent Claim
72 words
A video-conferencing system comprising a plurality of stations interconnected by a transmission system, each station including a screen for displaying images, said screen being simultaneously transparent and translucent; a camera located behind said screen for generating a video signal of images captured through said screen; a projector for displaying projected images on said screen, and means located between said camera and said screen for blocking said projected images from entering said camera.
Claim 5
Dependent Claim
34 words
The video-conferencing system of claim 2 wherein said blocking means is polarizing in a particular direction of polarization and blocks said projected images having a direction of polarization substantially orthogonal to said particular direction.
Claim 6
Dependent Claim
45 words
The video-conferencing system of claim 3 further comprising polarizing means located between said projector and said screen, said polarizer means having a direction of polarization orthogonal to said particular direction and passing said projected images having a direction of polarization orthogonal to said particular direction.
Claim 7
Dependent Claim
83 words
A video-conferencing system comprising a plurality of stations interconnected by a transmission system, each station including a screen for displaying images, said screen being simultaneously transparent and translucent, wherein said screen comprises a plurality of segments of polarizing material, alternate ones of said segments being positioned adjacent to one another and having orthogonal directions of polarization; a camera located behind said screen for generating a video signal of images captured through said screen; and a projector for displaying projected images on said screen.
Claim 8
Dependent Claim
83 words
A video-conferencing system comprising a plurality of stations interconnected by a transmission system, each station including a screen for displaying images, said screen being simultaneously transparent and translucent, wherein said screen comprises a plurality of segments of polarizing material, alternate ones of said segments being positioned adjacent to one another and having orthogonal directions of polarization; a camera located behind said screen for generating a video signal of images captured through said screen; and a projector for displaying projected images on said screen.
Claim 9
Dependent Claim
50 words
The video-conferencing system of claim 5 wherein said segments comprise translucent segments having a direction of polarization substantially parallel to the direction of polarization of said projected images and transparent segments having a direction of polarization substantially parallel to the direction of polarization of said images captured by said camera.
Claim 10
Dependent Claim
22 words
The video-conferencing system of claim 6 wherein said translucent segments include a diffusing surface for scattering said projected images from said projector.
Claim 11
Dependent Claim
21 words
The video-conferencing system of claim 7 wherein said diffusing surface is located on a side of said screen opposite said projector.
Claim 12
Dependent Claim
35 words
The video-conferencing system of claim 6 wherein said camera has a field of view and said camera is aligned with said screen such that said field of view of said camera substantially fills said screen.
Claim 13
Dependent Claim
190 words
A video-conferencing system comprising a plurality of stations interconnected by a transmission system, each station including a screen for displaying images, said screen being simultaneously transparent and translucent, wherein said screen includes an isotropic sheet having a first index of refraction, a birefringent sheet having a roughened surface, having said first index of refraction with respect to said images captured through said screen and polarized in a first direction of polarization and having a second index of refraction with respect to projected images polarized substantially orthogonal to said first direction of polarization, and an index-matching material between said roughened surface of said birefringent sheet and said isotropic sheet, said material having said first index of refraction, wherein upon projected images polarized substantially orthogonal to said first direction of polarization entering the screen, said orthogonally-polarized projected images encounter an index mismatch between said roughened surface of said birefringent sheet and said index-matching material and are scattered to display the projected images on the screen; a camera located behind said screen for generating a video signal of images captured through said screen; and a projector for displaying projected images on said screen.
Claim 14
Dependent Claim
190 words
A video-conferencing system comprising a plurality of stations interconnected by a transmission system, each station including a screen for displaying images, said screen being simultaneously transparent and translucent, wherein said screen includes an isotropic sheet having a first index of refraction, a birefringent sheet having a roughened surface, having said first index of refraction with respect to said images captured through said screen and polarized in a first direction of polarization and having a second index of refraction with respect to projected images polarized substantially orthogonal to said first direction of polarization, and an index-matching material between said roughened surface of said birefringent sheet and said isotropic sheet, said material having said first index of refraction, wherein upon projected images polarized substantially orthogonal to said first direction of polarization entering the screen, said orthogonally-polarized projected images encounter an index mismatch between said roughened surface of said birefringent sheet and said index-matching material and are scattered to display the projected images on the screen; a camera located behind said screen for generating a video signal of images captured through said screen; and a projector for displaying projected images on said screen.
Claim 15
Dependent Claim
100 words
A video-conferencing system comprising a plurality of stations interconnected by a transmission system, each station including a screen for displaying images, said screen being simultaneously transparent and translucent, wherein said screen includes a first array of segments for transmitting light through said screen and a second array of segments which are adjacent to and alternating with said segments of said first array, said second array of segments for diffusing light on said screen; a camera located behind said screen for generating a video signal of images captured through said screen; and a projector for displaying projected images on said screen.
Claim 16
Dependent Claim
100 words
A video-conferencing system comprising a plurality of stations interconnected by a transmission system, each station including a screen for displaying images, said screen being simultaneously transparent and translucent, wherein said screen includes a first array of segments for transmitting light through said screen and a second array of segments which are adjacent to and alternating with said segments of said first array, said second array of segments for diffusing light on said screen; a camera located behind said screen for generating a video signal of images captured through said screen; and a projector for displaying projected images on said screen.
Claim 17
Dependent Claim
68 words
The video-conferencing system of claim 11, wherein said screen comprises a plurality of prisms which are abutting one another, each said prism having a first facet and a second facet, said first array of segments including said first facet of each said prism, said second array of segments including said second facet of each said prism, and said second facet of each said prism having a diffusing surface.
Claim 18
Dependent Claim
33 words
The video-conferencing system of claim 12, wherein said prisms are abutting to form a vertical plane, said projector and said camera being positioned at an angle of substantially 26° to said vertical plane.
Claim 19
Dependent Claim
27 words
The video-conferencing system of claim 11, wherein said first and second arrays of segments comprise parallel elongated segments of polarizing material in tight alignment with each other.
Claim 20
Dependent Claim
42 words
The video-conferencing system of claim 11, wherein said segments of said first and second arrays comprise a polarizer sheet, segments of one of said first and second arrays further having translucent crystals in conjunction with an epoxy to form a diffusing surface.
Claim 21
Dependent Claim
34 words
The video-conferencing system of claim 11, wherein said segments of said first and second arrays comprise a polarizer sheet, and one of said first and second arrays being layered with half-wave planar retarder material.
Claim 22
Dependent Claim
50 words
A video-conferencing station comprising a screen for displaying images, said screen being simultaneously transparent and translucent; a camera located behind said screen for generating a video signal of images captured through said screen; and a projector for projecting images, said projected images being diffused at, and displayed on, said screen.
Claim 23
Dependent Claim
50 words
A video-conferencing station comprising a screen for displaying images, said screen being simultaneously transparent and translucent; a camera located behind said screen for generating a video signal of images captured through said screen; and a projector for projecting images, said projected images being diffused at, and displayed on, said screen.
Claim 24
Dependent Claim
119 words
A video-conferencing station comprising a screen for displaying images, said screen being simultaneously transparent and translucent; a camera located behind said screen for generating a video signal of images captured through said screen; a projector for displaying projected images on said screen; a first polarizer, located between said projector and said screen and having a first direction of polarization, for passing said projected images from said projector which are aligned with said first direction of polarization; and a second polarizer, located between said camera and said screen and having a second direction of polarization which is substantially orthogonal to said first direction of polarization, for blocking said projected images having said first direction of polarization from entering said camera.
Claim 25
Dependent Claim
119 words
A video-conferencing station comprising a screen for displaying images, said screen being simultaneously transparent and translucent; a camera located behind said screen for generating a video signal of images captured through said screen; a projector for displaying projected images on said screen; a first polarizer, located between said projector and said screen and having a first direction of polarization, for passing said projected images from said projector which are aligned with said first direction of polarization; and a second polarizer, located between said camera and said screen and having a second direction of polarization which is substantially orthogonal to said first direction of polarization, for blocking said projected images having said first direction of polarization from entering said camera.
Claim 26
Dependent Claim
79 words
A video-conferencing screen for use in a video-conferencing station, which includes a camera and a projector, comprising a first set of segments having a diffusing surface for displaying an image projected from the projector; and a second set of segments through which the camera can capture an image at the station, wherein said first set of segments are translucent with respect to the projected image and said second set of segments are transparent with respect to said captured image.
Claim 27
Dependent Claim
79 words
A video-conferencing screen for use in a video-conferencing station, which includes a camera and a projector, comprising a first set of segments having a diffusing surface for displaying an image projected from the projector; and a second set of segments through which the camera can capture an image at the station, wherein said first set of segments are translucent with respect to the projected image and said second set of segments are transparent with respect to said captured image.
Claim 28
Dependent Claim
28 words
The video-conferencing screen of claim 19 wherein each said segment of said first set is positioned adjacent to said segments of said second sets in an alternating fashion.
Claim 29
Dependent Claim
44 words
The video-conferencing screen of claim 20 wherein said segments of said first set have a first direction of polarization and said segments of said second set have a second direction of polarization, said first direction of polarization being substantially orthogonal to said second direction.
Claim 30
Dependent Claim
32 words
The video-conferencing screen of claim 21 wherein each segment of said first and said second sets are physically distinct and laid adjacent to one another such that the segments are aligned edge-to-edge.
Claim 31
Dependent Claim
25 words
The video-conferencing screen of claim 21 wherein said first and said second sets of segments comprise a continuous polarizer sheet patterned using a photolithographic process.
Claim 32
Dependent Claim
25 words
The video-conferencing screen of claim 21 wherein said first and said second sets of segments comprise a polarizer sheet layered with half-wave planar retarder material.
Claim 33
Dependent Claim
40 words
The video-conferencing screen of claim 21 further comprising prisms having a plurality of facets wherein said first set of segments comprises a first facet of each prism and said second set of segments comprises a second facet of each prism.
Claim 34
Dependent Claim
161 words
A video-conferencing screen for use in a video-conferencing station, which includes a camera for generating a video signal of images captured through the screen and a projector for displaying projected images on the screen, comprising: an isotropic sheet having a first index of refraction; a birefringent sheet having a roughened surface, having said first index of refraction with respect to projected images polarized in a first direction of polarization, and having a second index of refraction with respect to projected images polarized substantially orthogonal to said first direction of polarization; and an index-matching material between said roughened surface of said birefringent sheet and said isotropic sheet, said material having said first index of refraction, wherein upon projected images polarized substantially orthogonal to said first direction of polarization entering the screen, said orthogonally-polarized projected images encounter an index mismatch between said roughened surface of said birefringent sheet and said index-matching material and are scattered to display the projected images on the screen.
Claim 35
Dependent Claim
161 words
A video-conferencing screen for use in a video-conferencing station, which includes a camera for generating a video signal of images captured through the screen and a projector for displaying projected images on the screen, comprising: an isotropic sheet having a first index of refraction; a birefringent sheet having a roughened surface, having said first index of refraction with respect to projected images polarized in a first direction of polarization, and having a second index of refraction with respect to projected images polarized substantially orthogonal to said first direction of polarization; and an index-matching material between said roughened surface of said birefringent sheet and said isotropic sheet, said material having said first index of refraction, wherein upon projected images polarized substantially orthogonal to said first direction of polarization entering the screen, said orthogonally-polarized projected images encounter an index mismatch between said roughened surface of said birefringent sheet and said index-matching material and are scattered to display the projected images on the screen.
Claim 36
Dependent Claim
16 words
The video-conferencing screen of claim 26 wherein said birefringent sheet is comprised of liquid crystal material.
Claim 37
Dependent Claim
57 words
A display screen for a video-conferencing system comprising a first array of segments for transmitting light through said screen and a second array of segments which are adjacent to and alternating with said segments of said first array, said second array of segments for diffusing light on said screen, whereby said screen is simultaneously transparent and translucent.
Claim 38
Dependent Claim
57 words
A display screen for a video-conferencing system comprising a first array of segments for transmitting light through said screen and a second array of segments which are adjacent to and alternating with said segments of said first array, said second array of segments for diffusing light on said screen, whereby said screen is simultaneously transparent and translucent.
Claim 39
Dependent Claim
23 words
A display screen of claim 28 wherein segments of said first array and segments of said second array have orthogonal directions of polarization.
Claim 40
Dependent Claim
27 words
A display screen of claim 29 wherein said first and second arrays of segments comprise parallel elongated segments of polarizing material in tight alignment with each other.
Claim 41
Dependent Claim
42 words
A display screen of claim 29 wherein said segments of said first and second arrays comprise a polarizer sheet, segments of one of said first and second arrays further having translucent crystals in conjunction with an epoxy to form a diffusing surface.
Claim 42
Dependent Claim
34 words
A display screen of claim 28 wherein said segments of said first and second arrays comprise a polarizer sheet and one of said first and second arrays being layered with half-wave planar retarder material.
Claim 43
Dependent Claim
21 words
A display screen of claim 28 wherein said first and second arrays of segments comprise prisms having a plurality of facets.
References Cited (Backward Citations)
US5028314A
Cited
US5029988A
Cited
US4890314A
Cited
US4965819A
Cited
US4928301A
Cited
US5050961A
Cited
US5121343A
Cited
US5113285A
Cited
US5239373A
Cited
US5117285A
Cited
US5317405A
Cited
US5243413A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-03-20 | 1998-09-19 | 1999-03-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-03-20 | 2002-09-19 | 2003-03-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-03-20 | 2006-09-19 | 2007-03-21 | $7700.00 | Window Closed / Lapsed |