JPS59140485A - Television character display unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a television character display device that displays character patterns relating to character arrangements and combinations on a television screen.

<Prior Art> Some conventional television character display devices of this type are constructed by combining a signal recording/reproducing device such as a video disk player or a video tape recorder with a television receiver. By the way, signal recording and reproducing devices can create standard television signals by reproducing recorded signals from recording media such as video disks and video tapes, and by combining horizontal and vertical synchronization signals with this recorded signal. It has become. By the way, in such a television character display device, the character pattern signal is synchronized with the horizontal and vertical synchronization signals in order to display a character pattern based on the character pattern signal on the television screen. In such a television character display device, the character pattern can be reproduced by synchronizing the character pattern signal with the horizontal and vertical synchronization signals only when the signal recording and reproducing device can detect and reproduce the recorded signal. It is now possible to display it. However, even if it is not possible to detect and reproduce the recorded signal, there may be cases where it is desired to display just a character pattern on the television screen.

Purpose of the present invention The present invention provides a method for displaying a desired character pattern on a television screen not only when a signal recording and reproducing device can detect a recorded signal but also when it cannot detect a recorded signal. The purpose is to

<Embodiment> FIG. 1 is a circuit diagram showing the overall configuration of an embodiment of the present invention. Although this embodiment will be described as being applied to a video disc player as a signal recording/reproducing device, the scope of application also extends to video tape recorders and other signal recording/reproducing devices. The television character display device jf 1 of this embodiment includes a video disc player 2 and a television receiver 3. The video disc player 2 includes a recording signal detection circuit such as a pickup means that detects a recording signal recorded on a video disc (not shown), and a recording signal detection circuit 4 that applies horizontal and vertical synchronization signals to the output signal of the recording signal detection circuit 4. It includes a recording signal processing circuit 5 which produces a standard television signal by combining. The video disc player 2 also includes various operation keys for recording and reproducing signals of the video disc player 2, and display operation keys for selecting and operating the type and content of character patterns to be displayed. an operation section 6 that generates a signal corresponding to the valley operation key; a control circuit 7 that generates a control signal in response to the operation signal of the operation section 6; and a display that generates a character pattern signal based on the control signal of the control circuit 7. circuit B. The video disc player 2 further includes a signal mixing circuit 9 for mixing the output signal of the recording signal processing circuit 5 and the character pattern signal of the display circuit 8.

FIG. 2 is a circuit diagram showing the internal configuration of the display circuit 8,
This figure shows the main part of the example. The display circuits 8 are connected to the first . a first to which a second control signal is applied;
．． The second input terminals 9 and 1o, and the third input terminal to which horizontal and vertical synchronization signals are respectively applied from an external source, such as the recording signal processing circuit 5. Fourth input terminal 11.12 and signal mixing circuit 9
and an output terminal 13 for outputting a character pattern signal obtained by combining horizontal, vertical, and vertical synchronization signals. The display circuit 8 includes a decoder 14 that decodes a first control signal applied from the control circuit 7 via its first input terminal 9. Here, the first control signal of the control circuit 7 drives and controls the display circuit 8 in order to display a character pattern corresponding to the operation of the operation keys on the operation unit 6 on the television screen of the television receiver 3. It is something to do. Decoder 14
provides an output corresponding to the first control signal applied via the first input terminal 9 to the character pattern signal generation circuit 15.

The character pattern signal generation circuit 15 is supplied with a reference signal and horizontal and vertical synchronization signals as described later, and this character pattern signal generation circuit 16 has contents based on the output of the decoder 14, and Generates character pattern signals synchronized with each signal.

16 is a reference signal generation circuit that generates a reference signal;
7 and 18 are a horizontal synchronizing signal generating circuit and a vertical synchronizing signal generating circuit, respectively. The plane synchronous signal generation circuit 17.18
receives a reference signal from the reference signal generation circuit 16, and generates horizontal and vertical synchronization signals, respectively.

19 supplies the horizontal and vertical synchronization signals from the surface synchronization signal generation circuits 17 and 18 to the character pattern signal generation circuit 15, or the third. Fourth input terminal 11.1
This is a synchronization signal selection circuit that selects whether to apply each horizontal or vertical synchronization signal from the outside via 2.

This synchronization signal selection circuit 19 therefore includes a horizontal synchronization signal selection switch 19a and a vertical synchronization signal selection switch 19.
b. Both switches 19a and 19b are switched in response to a second control signal applied from the control circuit 7 via the second input terminal 10. Reference numeral 20 denotes a synchronization signal control circuit for controlling whether or not to combine the character pattern signal from the character pattern signal generation circuit 15 with both the horizontal and vertical synchronization signals from the surface synchronization signal generation circuits 17 and 18. In this synchronization signal control circuit 20, both switches 19a+19b of the synchronization signal selection circuit 19 are connected to the third switch. 4th input terminal 11.12
When it is switched to the side, the character pattern signal generation circuit 1
The synchronization signal generation circuit 1 receives the character pattern signal from 5.
7. Do not combine the horizontal and vertical synchronization signals from 18,
On the contrary, both the switches 19a! 191) is switched to the synchronous signal generation circuit 17°1B side, the above-mentioned synthesis is performed.

Therefore, the character pattern signal from the character pattern signal generation circuit 15 is either the synchronization signal from the synchronization period signal generation circuit 17, 18 or the third . It is generated in synchronization with one of the respective synchronization signals input via the fourth input terminal 11, 12. If the character pattern signal is synchronized with the former synchronization signal, it is combined with the cough synchronization signal in the synchronization signal control circuit 20 and output to the signal mixing circuit 9 via the output terminal 13. On the other hand, if this character pattern signal is synchronized with the latter synchronization signal, the recording signal is detected and the recording signal processing circuit 5 sends the signal to the signal mixing circuit 9.
A standard television signal is input and displayed. Therefore, this character pattern signal is not combined with the synchronization signal from the synchronization period signal generation circuits 17 and 18 in the synchronization signal control circuit 20, but is combined with the synchronization signal from the recording signal processing circuit 5 in the signal mixing circuit 9. become. As described above, according to this embodiment, when the recording signal is not detected and therefore the character pattern signal cannot be synthesized with the horizontal and vertical synchronizing signals of the standard television signal, the display circuit 80 A character pattern signal which is synchronized with each synchronizing signal from the synchronizing image signal generating circuits 17 and 18 and in which these synchronizing signals are synthesized can be given from the display circuit 8 to the signal mixing circuit 9. Therefore, even if no recording signal is detected, the character pattern can be displayed on the television screen of the television receiver 3.

<Effects> As described above, according to the present invention, since the display circuit is provided with a circuit that generates each horizontal and vertical synchronization signal, the signal recording/reproducing device cannot detect the recorded signal and cannot detect the horizontal and vertical synchronization signals based on the recorded signal.・Even if it is not possible to synchronize the character pattern signal with each vertical synchronization signal, the character pattern signal can be synchronized with each horizontal and vertical synchronization signal from the synchronization signal generation circuit in the display circuit, and this synchronization signal can be used as the character pattern signal. It becomes possible to display a character pattern by compositing the text and feeding it to a television receiver.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with FIG. 1 being a circuit diagram showing the overall configuration, and FIG. 2 being an internal circuit diagram of the main part of the display circuit. 1...Television character display device, 2...Signal recording and reproducing device, 3...Television receiver, 8...Display circuit, 1
5. Character pattern signal generation circuit, 17. Horizontal synchronization signal generation circuit, 18. Vertical synchronization signal generation circuit, 19.
Synchronous signal selection circuit, 20... Synchronous signal control circuit. Patent applicant: Sharp Corporation Representative: Patent attorney Kazuhide Okada

Claims (1)

[Claims] (1) A television that has a display circuit that outputs a character pattern signal and displays a character pattern by supplying a signal made by mixing a standard television signal with a character pattern signal from the display circuit to a television receiver. In a television character display device, the display circuit is provided with a circuit that generates horizontal and vertical synchronization signals, and when a standard television signal cannot be obtained, the horizontal and vertical synchronization signals from the synchronization signal generation circuit are used. A television character display device that synchronizes character pattern signals and provides a signal obtained by combining both synchronization signals into a character pattern signal to a television receiver.