On-screen channel display

• US 4,081,797 A
• Filed: 02/21/1975
• Issued: 03/28/1978
• Est. Priority Date: 11/03/1972
• Status: Expired due to Term

• Current Assignee: Packard Bell NEC Inc. (Acer, Inc.)
• Original Assignee: Heath Company
• Inventors: Olson, John Emery
• Primary Examiner(s): Trafton, David L.
• Application Number:
  US05/551,918
• Time in Patent Office: 1,131 Days
• Field of Search: 340/324 AD, 178/DIG. 6, 178/DIG. 15, 358/192
• US Class Current: 348/570
• CPC Class Codes: G09G 1/165 Details of a display terminal using a CRT, the details relating to the control arrangement of the display terminal and to the interfaces thereto details suitable for both CRT and flat panel G09G5/003; specific for a flat panel G09G3/2092
• CPC Class Codes: G09G 2320/08 Arrangements within a display terminal for setting, manually or automatically, display parameters of the display terminal
• CPC Class Codes: H04N 5/45 Picture in picture , e.g. displaying simultaneously another television channel in a region of the screen

Abstract

An on-screen television display including means internally of the receiver for generating characters to indicate the channel number, time of day or other data. The system includes circuit means responsive to the horizontal and vertical sync signals of a television receiver for positioning and timing of the display. BCD data is coupled to a character generator, and the output of the character generator is then multiplexed with positioning and timing signals. The multiplexed output is coupled to a video interface which supplies the video signal to the cathode ray tube.

Claims

1. A system for displaying a character indicating the channel being received on the raster of a broadcast television receiver comprising:

means for developing coded data indicative of the character to be displayed, decoding means having a plurality of inputs and outputs, means for coupling the coded data to given inputs of said decoding means, said decoding means being a device for developing signals on a predetermined combination of outputs in response to each selected coded input, circuit means for processing the signal on each of said outputs of said decoder into a given line segment generated video signal and comprising means for multiplexing the outputs of said decoding means in accordance with the line of scan of the beam of the cathode ray tube of said broadcast television receiver, and means for adding the generated video signal in a video circuit of said broadcast television receiver to develop a character display on the raster of the television receiver in addition to any other signal being processed by said video circuit.

2. A display system in accordance with claim 1 wherein said decoding means comprises a seven segment decoder.

3. A display system in accordance with claim 2 wherein a line counter is provided to count horizontal scans of the cathode ray beam and wherein the output of said counter is coupled to said multiplexer to control the same.

4. A display system in accordance with claim 1 wherein said decoder is a seven segment decoder and wherein means are provided to gate the data output of said decoder which represent the vertical segments of the character to be displayed during given horizontal scans of the beam of the cathode ray tube.

5. A system ,in accordance with claim 1 including timing circuit means, means for multiplexing coded data representing each of said characters in accordance with timing signals from said timing circuit means, a seven segment decoder for decoding said multiplexed data, and means for using said decoded data to apply a video signal to the cathode ray tube of the television receiver.

6. A display system in accordance with claim 5 wherein there is provided an oscillator, means for keying the operation of the oscillator to the horizontal sync of the television receiver, and a counter for counting an output of said oscillator and for producing said timing signals.

7. A channel number display system in accordance with claim 6 wherein said data multiplexer has units digits gates and tens digits gates, said timing signal multiplexing data between said units and tens digits gates into at least four output lines, and means for coupling said multiplexed data to inputs of said seven segment decoder.

8. A channel number display system in accordance with claim 7 wherein means are provided to blank the display system output for a time interval between the switching of said data multiplexer from the units digits gates to the tens digits gates to provide spacing between the units and tens characters on the raster of the cathode ray tube.

9. A channel number display system in accordance with claim 8 wherein select means are provided to select one of a greater number of variable character displays, said means including a BCD signal responsive select circuit.

10. A channel number display system in accordance with claim 9 wherein said select means includes a four-six character select circuit for selecting either four or six character display.

11. A system for displaying a character on the raster of a television receiver comprising:

means for developing coded data indicative of the character to be displayed, a seven segment decoder, means for coupling the coded data to the input of the seven segment decoder, means for using the output of the seven segment decoder to illuminate a seven segment display on the raster of a cathode ray tube, and wherein three outputs of the seven segment decoder represent the horizontal segments of the character to be displayed and the remaining four outputs represent the vertical segments thereof, and wherein there is provided a multiplexer, a horizontal scan counter, means for coupling the counter outputs to the multiplexer, means for coupling the three horizontal segment outputs to the multiplexer, a timing counter, means for using the timing counter to gate the four vertical segment outputs during each scan associated with the character display, and means for coupling the four gated vertical segment outputs to the multiplexer.

12. A display system in accordance with claim 11 wherein there is provided an oscillator, means for keying the oscillator to the horizontal scan of the cathode ray beam, said oscillator having a frequency substantially higher than the horizontal line frequency of the cathode ray tube, means for coupling the output of the oscillator to the timing counter to control the same.

13. A display system in accordance with claim 12 wherein means are provided to use the horizontal sync signal of the television receiver to enable said timing counter.

14. Apparatus for use with a television receiver, said receiver comprising a horizontal scanning circuit, a vertical scanning circuit, a video signal circuit, and a display device coupled to said scanning and video signal circuits, and creating a character on said display device in the form of line segments oriented in generally horizontal and vertical directions and superimposed over other information displayed thereon and comprising:

data means for developing coded data indicative of the character to be displayed;

decoding means having a plurality of outputs and producing at each of said outputs a signal representative of the presence of a corresponding line segment in the character to be displayed;

an oscillator coupled to said horizontal scanning circuit and synchronized to the operation of said horizontal scanning circuit and producing a signal at a frequency greater than the horizontal scanning frequency;

counting means coupled to the output of said oscillator and developing signals representative of the position of the horizontal scan;

gating means coupled to said decoding means and said counting means and gating said signals representative of the presence of a corresponding generally vertical line segment in response to the position of the horizontal scan;

matrix means for matrixing said gated signals representative of the presence of corresponding generally vertical line segments and said signals representative of corresponding generally horizontal line segments to form a plurality of line signals each representative of the video signal required to generate said character on said display device during a horizontal scan;

signal selection means for selecting one of said line signals in accord with the position of the vertical scan; and

combining means coupled to said video signal circuit for combining said selected line signal with a signal representative of said other information displayed on said display device.

15. The apparatus of claim 14 wherein said character is displayed in the form of the presence or absence of seven line segments and said decoding means comprises a seven segment decoder having seven outputs and producing at each of said outputs a signal representative of the presence of a corresponding one of said seven line segments in the character to be displayed.

16. The apparatus of claim 14 creating at least two characters on said display device wherein said data means develops coded data indicative of the characters to be displayed and said apparatus further comprises multiplex means coupled to said data means, said decoding means and said counting circuitry for applying to said decoding means coded data indicative of different characters to be displayed in response to the position of the horizontal scan.

17. The apparatus of claim 16 further comprising means for preventing the display of said characters for a time interval including the switching of said multiplex means to provide spacing between said characters.

18. The apparatus of claim 14 further comprising a time delay circuit coupled between said oscillator and said horizontal scanning circuit and preventing the operation of said oscillator until a predetermined time period has elapsed following the commencement of a horizontal scan.

19. Apparatus for use with a television receiver, said receiver comprising a first scanning circuit for scanning in a first direction, a second scanning circuit for scanning in a second direction generally perpendicular to said first direction, a video signal circuit, and a display device coupled to said scanning and video signal circuits, and creating a character on said display device in the form of line segments oriented in generally said first and second directions and superimposed over other information displayed thereon and comprising:

data means for developing coded data indicative of the character to be displayed;

decoding means having a plurality of outputs and producing at each of said outputs a signal representative of the presence of a corresponding line segment in the character to be displayed;

timing and gating means coupled to said decoding means and said first scanning circuit and gating said signals representative of the presence of a corresponding line segment in said second direction in response to the position of the scan in said first direction;

matrix means for matrixing said gated signals representative of the presence of corresponding line segments in said second direction and signals representative of corresponding line segments in said first direction to form a plurality of line signals each representative of the video signal required to generate said character on said display device during a scan in said first direction;

signal selection means for selecting one of said line signals in accord with the position of the scan in said second direction; and

combining means coupled to said video signal circuit for combining said selected line signal with a signal representative of said other information displayed on said display device.

20. A system for displaying at least two characters on the raster of a television receiver comprising:

an oscillator, means for keying the operation of the oscillator to the horizontal sync of the television receiver, a counter for counting an output of said oscillator and for producing timing signals, means for developing and multiplexing coded data representing each of said characters to be displayed in accordance with said timing signals, a seven segment decoder having a plurality of inputs and outputs for developing signals on a predetermined combination of said outputs in response to each selected coded input, means for coupling the coded data to given inputs of said decoder, circuit means for processing the signal on each of said outputs of said decoder into a given line segment generated video signal, and means for adding the generated video signal in the television receiver video circuit to develop a character display on the raster of the television receiver in addition to any other signal being processed by said video circuit.

21. A channel number display system in accordance with claim 20 wherein said data developing and multiplexing means has units digits gates and tens digits gates, said timing signal multiplexing data between said units and tens digits gates into at least four output lines, and means for coupling said multiplexing data to inputs of said seven segment decoder.

22. A channel number display system in accordance with claim 21 wherein means are provided to blank the display system output for a time interval between the switching of said data developing and multiplexing means from the units digits gates to the tens digits gates to provide spacing between the units and tens characters on the raster of the cathode ray tube.

23. A channel number display system in accordance with claim 22 wherein select means are provided to select one of a greater number of variable character displays, said means including a BCD signal responsive select circuit.

24. A channel number display system in accordance with claim 23 wherein said select means includes a four-six character select circuit for selecting either four or six character display.

25. A system for displaying a character indicating the channel being received on the raster of a broadcast television receiver comprising:

means for developing coded data indicative of the character to be displayed, decoding means having a plurality of inputs and outputs, means for coupling the coded data to given inputs of said decoding means, said decoding means being a device for developing signals on a predetermined combination of outputs in response to each selected coded input, circuit means for processing the signal on each of said outputs of said decoder into a given line segment generated video signal and comprising an oscillator having a frequency substantially higher than the horizontal line frequency of said broadcast television receiver and means responsive to the horizontal synchronization signal of received broadcast television signals for keying said oscillator, and means for adding the generated video signal in a video circuit of said broadcast television receiver to develop a character display on the raster of the television receiver in addition to any other signal being processed by said video circuit.

26. A display system in accordance with claim 25 wherein said circuit means further comprises counting means coupled to the output of said oscillator and developing signals indicative of the horizontal position of the beam of the cathode ray tube of said broadcast television receiver.

27. A display system in accordance with claim 26 further comprising means coupled to the horizontal scan circuitry of said broadcast television receiver and said counting means for resetting said counting means.

28. A system for displaying a character indicating the channel being received on the raster of a broadcast television receiver comprising:

means for developing coded data indicative of the character to be displayed, decoding means having a plurality of inputs and outputs, means for coupling the coded data to given inputs of said decoding means, said decoding means being a device for developing signals on a predetermined combination of outputs in response to each selected coded input, circuit means for processing the signal on each of said outputs of said decoder into a given line segment generated video signal and comprising an oscillator having a frequency substantially higher than the horizontal line frequency of said broadcast television receiver, means responsive to the horizontal synchronization signal of received broadcast television signals for keying said oscillator, and means for multiplexing the outputs of said decoding means in accordance with the line of scan of the beam of the cathode ray tube of said broadcast television receiver, and means for adding the generated video signal in a video circuit of said broadcast television receiver to develop a character display on the raster of the television receiver in addition to any other signal being processed by said video circuit.

29. A display system in accordance with claim 28 wherein said decoding means comprises a seven segment decoder.

30. A display system in accordance with claim 28 wherein a line counter is provided to count horizontal scans of the cathode ray beam and wherein the output of said counter is coupled to said multiplexing means to control the same.

31. A display system in accordance with claim 30 further comprising means coupled to the horizontal scan circuitry of said broadcast television receiver and said counting means for resetting said counting means.

32. A system for displaying a character indicative of the channel being received on the picture display device of a broadcast television receiver comprising:

means for developing data indicative of the character to be displayed, decoding means having a plurality of inputs and outputs, means for coupling said data to inputs of said decoding means, said decoding means being a device for developing signals on a predetermined combination of outputs in response to each data input, circuit means for processing the signal on said outputs of said decoder into a video signal for generating a line segment character and including an oscillator having a frequency substantially higher than the horizontal line frequency of said broadcast television receiver and means responsive to the horizontal synchronization signal of received broadcast television signals for keying said oscillator, and means for adding said video signal to other video signals being processed by said broadcast television receiver to develop a character display on said picture display device.

33. A system for displaying a character indicative of the channel being received on the picture display device of a broadcast television receiver comprising:

means for developing data indicative of the character to be displayed, decoding means having a plurality of inputs and outputs, means for coupling said data to inputs of said decoding means, said decoding means being a device for developing signals on a predetermined combination of outputs in response to each data input, circuit means for processing the signal on said outputs of said decoder into a video signal for generating a line segment character and including an oscillator having a frequency substantially higher than the horizontal line frequency of said broadcast television receiver and means responsive to the horizontal synchronization circuitry of said broadcast television receiver for keying said oscillator, and means for adding said video signal to other video signals being processed by said broadcast television receiver to develop a character display on said picture display device.