Projection television system employing optics through which transmitted infrared television signals are received

• US 5,170,258 A
• Filed: 10/29/1991
• Issued: 12/08/1992
• Est. Priority Date: 11/06/1990
• Status: Expired due to Fees

• Current Assignee: Deutsche ITT Industries GmbH
• Original Assignee: Deutsche ITT Industries GmbH
• Inventors: Micic, Ljubomir, Heberle, Klaus
• Primary Examiner(s): Groody, James J.
• Assistant Examiner(s): METJAHIC, SAFET
• Application Number:
  US07/784,494
• Time in Patent Office: 406 Days
• Field of Search: 358/60, 358/113, 358/56, 358/64, 358/93, 358/230, 358/231, 358/237, 359/350, 359/113, 359/129, 359/131, 359/143
• US Class Current: 348/744
• CPC Class Codes: H04N 9/3179 Video signal processing therefor

Abstract

A projection television system includes a projection unit having an optical element through which infrared television signals are received. The received signals are processed to provide a television image display which is projected for viewing. Received television signals from a TV station or cable are converted to infrared signals and transmitted along a given axis of an infrared transmission link extending between an infrared transmitter, remotely positioned from the projection unit, to an infrared detector, located in the projection unit. The detector converts the infrared TV signal into a video signal which signal is processed by the projection receiver to provide the image for display. The infrared transmitter, the optical element and the detector are aligned along a given axis which is also the optical axis of the system.

Claims

1. A projection television system comprising:

means for transmitting an infrared television signal along a given axis; and

a projection television means including projection optics adapted to receive said transmitted infrared signal via said optics, including means for converting said received signal via said optics into an image signal and for returning said image signal to be displayed at a remote location through said projection optics.

2. The projection television system according to claim 1, wherein said optics are aligned on said given axis which axis is the optical axis for said system.

3. The projection television system according to claim 1, wherein said projection television means includes means for converting said received signal into a television image display, which image display is projected via said projection optics to a remote location.

4. The projection television system according to claim 2, further including a projection screen positioned at said remote location and adapted to display said image.

5. The projection television system according to claim 2, wherein said means for transmitting is located below said projection television means wherein said optical axis is at a given angle with respect to the horizontal.

6. The projection television system according to claim 1, wherein said infrared television signal is a digitized composite color signal.

7. The projection television system according to claim 2, wherein said means for converting includes an infrared detector for converting said transmitted infrared signal into an electrical television signal.

8. The projection television system according to claim 6, wherein said infrared detector is a photodiode detector.

9. The projection television system according to claim 1, wherein means for transmitting includes three spatially separated transmitter diodes which transmit R, G and B signals, respectively, together with synchronizing signals, and that the projection unit contains three correspondingly spatially separated infrared detectors.

10. The projection television system according to claim 6, wherein said infrared detector is a multiple split element, and that from the individual output signals of the multiple split element, a signal is derived which corresponds to the distortion of the projected image.

11. The projection television system according to claim 10, including means responsive to the output signals of said multiple split element to provide a control signal which serves to automatically correct the distortion of said projected image.