JPS63288584A - Multi-scanning type television receiver - Google Patents

Abstract

PURPOSE:To prevent confusion due to the difference of horizontal frequencies even when various equipments to output signals whose horizontal frequencies are different are changed-over and used by discriminating that it is high resolution input or a normal image input from the horizontal frequency of an input signal and displaying this. CONSTITUTION:An FVC 31 to form a mode detecting circuit 11 to detect the horizontal frequency of an input signal is provided. By the detecting output of this detecting circuit 11, a horizontal oscillating frequency is changed-over and by discriminating means 81 and 81, it is discriminated that the input signal is a high resolution input time or a normal image input time. By these discriminating means 81 and 82, a driving circuit 83 which is a display means, an invertor 84 and light emitting diodes 85 and 86 are operated and the display of the high resolution input time or the normal image input time is executed. Thus, even when various devices to output signals whose horizontal frequencies are different are changed-over and used, confusion due to the difference of the horizontal frequencies can be prevented.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention can be used to increase the number of scanning lines to 2 in addition to normal television broadcast image reception.
The present invention relates to a multi-scan television receiver capable of receiving video signals of different horizontal frequencies from a converter or the like that doubles the frequency.

(Prior art) For example, in an NTSC television signal, the vertical frequency is approximately 6011 Hz and the horizontal frequency is approximately 15.75 KHz.
The image is formed. In response, a conversion device has been proposed that doubles the number of scanning lines through arithmetic processing or the like to improve the quality of the received image. When using this device,
The signal to be outputted now has a vertical frequency of about 6011 z and a horizontal frequency of about 31.5 KHz.

In addition, there is a computer output signal with a so-called +11ipII image resolution display having a horizontal frequency of approximately 24K)12. Furthermore, in so-called high-definition television, the horizontal frequency is expected to be approximately 33.75 KHz.

Currently, a multi-scanning television receiver has been proposed which allows a single device to receive various signals having different horizontal frequencies.

[Problem to be solved by the invention]

Incidentally, in such a multi-scanning television receiver, various devices that output signals with different horizontal frequencies may be connected and switched to receive images.

On the other hand, as the horizontal frequency increases, the fineness of the screen also increases. Therefore, immediately after signal switching, especially when a normal signal is received thinking that it is double speed due to a misunderstanding or preconception, there is a risk that equipment failure or connection error may be mistaken.

In view of this point, the present invention aims to propose a device that does not cause confusion due to differences in horizontal frequencies even when various devices that output signals with different horizontal frequencies are switched and used.

[Means to solve the problem]

The present invention provides an F mode detection circuit (11) that detects the horizontal frequency of an input signal in a multi-scan television receiver that receives video signals of different horizontal frequencies.
A VC (31) is provided, and the horizontal oscillation frequency is switched by the detection output of the cono mode detection circuit (11), and the horizontal frequency of the input signal is higher than a predetermined frequency according to the detection output of the mode detection circuit (11). Discrimination means (81) (82) are provided to distinguish between normal image input and normal image input when the horizontal frequency of the input signal is lower than a predetermined frequency. Display means (83) for displaying the time (
84), (85), and (86).

[Effect]

According to this configuration, when input signals having different horizontal frequencies are switched and received, the horizontal oscillation frequency is switched by the detection output of the mote detection circuit (11), and the input signal is switched by the identification means (81) (82). It is identified whether it is high resolution input or normal image input, and the display means (83) is identified by the identification means (81) (82).
) (84) (85) (86) are operated,
A display is made when inputting a high resolution image or when inputting a normal image.

〔Example〕

Hereinafter, one embodiment of the multi-scanning television receiver of the present invention will be described with reference to the drawings.

First, a multi-scan television receiver proposed by the applicant will be explained.

FIG. 3 shows an overall block diagram of a typical television broadcast chainer or video tape recorder,
When receiving a normal video signal from a video disc player, satellite broadcast tuner, or some personal computers, the video signal supplied to the input terminal +11 passes through the video process circuit (2) and the RGB process circuit (3). ) to form three primary color signals. In addition, the video/RGB switching signal supplied to the input terminal (4) is supplied to the RGB processing circuit (3), and the three primary color signals from the selected video signal are thereby output to the output circuit (5).
) is supplied to cathode rays [(6).

In addition, the video signal from the input terminal (1) is transferred to the sync separation circuit (
7), and the vertical and horizontal synchronization signals are separated.

Furthermore, the switching signal from the input terminal (4) is transmitted to the synchronous separation circuit (
7), whereby the vertical synchronizing signal from the selected video signal is supplied to the vertical deflection circuit (8), and the vertical deflection signal formed is applied to the vertical deflection yoke (9) of the cathode ray tube (6). Supplied. Further, the horizontal synchronization signal from the video signal selected by the synchronization separation circuit (7) is transmitted to the AFC circuit (l).
O) and the mode detection circuit (11), and this AN
(No. 4 from the C circuit (10) is supplied to the horizontal oscillation circuit (12), and the normal control signal from the mode detection circuit (11) is supplied to the horizontal oscillation circuit (12). The signal from the horizontal oscillation circuit (12) is supplied to the horizontal deflection circuit (13), and the formed horizontal deflection signal is supplied to the horizontal deflection yoke (14) of the cathode ray tube (6). ) is supplied to a high voltage generation circuit (15) such as a flyback transformer, and the generated high voltage is supplied to the high voltage terminal (16) of the cathode ray tube (6), and part of the signal is supplied to the AFC circuit (15). 1o).

Furthermore, commercial power from the power source (17) is supplied to the power supply circuit (1
8), and a voltage at the time of passage corresponding to the signal '' is supplied from the mode detection circuit (11) to the horizontal deflection circuit (13). Also, commercial power from the power supply input (17) is supplied to another power supply circuit (19), and the voltage formed is supplied to other circuits.

This allows normal video signal reception. On the other hand, it receives digital or analog R, G, and B primary color signals (hereinafter referred to as RGB signals) from some personal combinators, so-called captain demodulators, teletext demodulators, or scan converters. In this case, input terminal (2ON) (20G) (20B
) Digital RGB signals supplied to the input terminal (2)
1R) (21G) (21B> The analog RG B (No. 4 and the selector switch (22)
It is selected by the switching signal from the input terminal (4) and supplied to the RGB process path (3), and is supplied to the output circuit (5).
).

Further, the digital synchronization signal from the input terminal (20S) and the analog synchronization signal from the input terminal (21S) are selected by the changeover switch (23) and supplied to the synchronization separation circuit (7), and the input terminal (4) It is selected by a switching signal from , and is supplied to a vertical deflection circuit (8) and an AFC circuit (lO).

Furthermore, the signal from the synchronization separation circuit (7) is supplied to the mode detection circuit (11), and a control signal corresponding to the frequency of the horizontal synchronization signal is formed, and the signal is sent to the horizontal oscillation circuit (12), the horizontal deflection circuit (13), and the power supply. It is supplied to the circuit (18).

As a result, digital or analog 1 (CB double signal reception) is performed.Furthermore, when performing so-called superimposed image reception in which RGB signals are displayed superimposed on the above-mentioned normal video signal, the input terminal (4) The supplied switching signal is set to RGB mode, and the input terminal (24
) are supplied to the RG B 7" process circuit (3), and the Ys signal indicating the position of the superimposed signal and the Ym signal indicating the superimposed range are supplied to the RG B 7" process circuit (3), and between these YsYm signals Switching between a video signal and an RGB signal is performed.

Various signals are received in the manner described above.

Further, in the above-described apparatus, the horizontal deflection system is specifically configured as follows. In Fig. 4, the synchronization separation circuit (
The horizontal synchronizing signal from 7) is supplied to a frequency-voltage conversion circuit (FVC) (31) constituting the mode detection circuit (11) to form a voltage according to the horizontal frequency. This voltage is supplied to a voltage controlled oscillator (VCO) (34) constituting the horizontal oscillation circuit (12) through a limiter circuit (32) that determines the lower limit and a buffer (B) amplifier (33). The oscillation output of this VCO (34) is the drive circuit (35)
The signal is supplied to the switching transistor (36) constituting the horizontal deflection circuit (13) through the horizontal deflection circuit (13).

In addition, the voltage from the FVC (31) is passed through the limiter circuit (37) that adds the upper and lower limits, and the control amplifier (38) to the rs#
It is supplied to, for example, a YZ type parametric power supply circuit (39) that constitutes the circuit (18). This power supply circuit (39
) output voltage is passed through the voltage divider circuit (40) to the amplifier (38
) to stabilize the output voltage. This output voltage is supplied to a flyback transformer (41).

A transistor (36) is connected in series to this flyback transformer (41). Also, this transistor (36
) in parallel with a damper diode (42).

A series circuit of a resonance capacitor (43), a horizontal deflection yoke (14), and a figure-8 correction capacitor (44) is connected.

Further, the horizontal synchronization signal is supplied to the detection circuit (45) constituting the AFC circuit (lO), and the transistor (36
) is supplied to a detection circuit (45) to form an Al'C signal. This signal is supplied to the rVco (34) (7) control terminal through a low pass filter (LPF) (47).

Furthermore, a switch circuit (
Capacitors (49) and (50) are connected through 48). In addition, in parallel with the S-shaped correction capacitor (44),
Capacitor (52) (5) through switch circuit (51)
3) is connected. Also, the voltage from FVC (31) is
For example, it is supplied to a comparator circuit (54) for binary comparison corresponding to voltages of 20 Hz and 30 KHz of the human horizontal frequency, and is applied to voltages below 20 KH2, 20 to 30 KHz, and 30 KHz.
Three-value comparison outputs corresponding to each of the above ranges are formed, and switch circuits (4B) and (5
Control is performed so that both of the two switches built in 1) are turned off or one of them is turned on.

As a result, in this horizontal deflection system, vCO (34
), an oscillation signal that varies from 15 to 34 KHz in synchronization with the input horizontal synchronizing signal is formed to perform horizontal deflection, and the power supply circuit (39) varies from 58 to 123 volts, for example, depending on the horizontal frequency. A voltage is generated to control the amplitude of the horizontal deflection to be constant. Also, the resonance capacitor (43) and the 3-character correction capacitor (44)
) in parallel with the capacitor (4
9) (50) and (52) (53) are connected,
The characteristics of each are corrected.

Further, in the above-described apparatus, the vertically deflected yarn is specifically constructed as follows. In Fig. 5, the synchronous separation circuit (7
) is supplied to a sawtooth wave oscillator (61) constituting the vertical deflection circuit (8), and for example, a sawtooth wave is formed by charging and discharging a capacitor (62) with current # (63). be done. This sawtooth wave is fed to a comparator circuit (64) and is used to indicate a predetermined voltage range and below or above the 3
A value comparison output is formed, and this comparison output is an up-down counter.

(LjDC) (65) is supplied to the control terminal. A vertical synchronization signal is supplied to the counting terminal of this UDC (65). The count value of this UDC (65) is -DA conversion circuit (L
) AC) (66), and a current source (63) is controlled by the converted analog value.

Therefore, a sawtooth wave whose peak value (amplitude) is controlled within a predetermined voltage range is extracted from the sawtooth wave oscillator (61), regardless of the frequency of the vertical synchronization signal. This sawtooth wave is supplied to the vertical deflection yoke (9) through an output circuit (67).

Furthermore, a capacitor (8B) is connected in series to this deflection yoke (9).
), a series circuit of a resistor (69) is connected, and a voltage dividing circuit (70) is connected in parallel to this resistor (69). The divided voltage output of this voltage dividing circuit (70) is supplied to an output circuit (67).

This ensures that vertical deflection always has a constant amplitude even if the vertical frequency changes. Furthermore, by making one of the resistors constituting the voltage dividing circuit (70) variable, the amplitude of the vertical deflection can be arbitrarily controlled.

Furthermore, another set (oscillator (71) to DAC (76)) of the sawtooth wave oscillator (61) to AC (66) is provided, and the output value of the DAC (7B) of this circuit is used as the bin distortion correction signal. For example, a parabolic signal with a vertical period from the midpoint of the connection between the deflection yoke (9) and the capacitor (68) is supplied to the formation circuit (77), and a bin distortion correction signal is supplied to the formation circuit (77). It is formed. This signal is supplied to the pin distortion correction circuit.

In this manner, in the above-described apparatus, the necessary horizontal and vertical deflections are performed in accordance with various different horizontal and vertical frequencies, and various signals are received.

In this example, this multi-scanning television receiver is constructed as shown in FIGS. 1 and 2.

That is, in FIG. 1, (81) indicates a comparison circuit, and the output voltage of the FVC (31) constituting the mode detection circuit (11) is supplied to one end of this comparison circuit (81). The other end is grounded via a reference voltage source (82). In this case, the reference voltage value of the reference voltage source (82) is set to, for example, the FVC (
Set equal to the output voltage value of 31).

The comparison output of this comparison circuit (81) is supplied to a drive circuit (83), and the output signal of this drive circuit (83) is sent to a light emitting diode (85) for "normal" display via an inverter circuit (84). The cathode of this light emitting diode (85) is grounded. Also, a drive circuit (83)
is applied to the anode of a light emitting diode (86) of the "high scan" display layer;
6) Ground the cathode.

In this case, when inputting a normal image with a human horizontal frequency of about 15.75 KHz, the FVC (31) is output from the comparison circuit (81).
The output voltage of the reference voltage source (82) is compared with the reference voltage value of the reference voltage source (82) so that a low level signal that causes the light emitting diode (85) to emit light is output as an output, and the input horizontal frequency exceeds 20KH2 (24KHz, 31.5). When inputting high resolution of Hz or 33.75Ktlz, the comparison circuit (
81) outputs a high level No. 415 that causes the light emitting diode (86) to emit light as a comparison output, and also uses the light emitting diodes (85) and (86) for displaying "normal" and "high scan". As shown in Figure 2, the front panel (87
) normal display section (88) and high scan display section (
89).

According to this configuration, a device that outputs signals with different horizontal frequencies, such as a computer with a high-resolution display with a horizontal frequency of about 24 KHz, a high-definition television decoder with a horizontal frequency of about 33.75 KHz, etc., can be connected and switched to receive the image. When receiving normal television broadcasting with a horizontal frequency of about 15.75 KHz, the horizontal synchronization signal with a horizontal frequency of about 15.75 KHz is sent from the synchronization separation circuit (7) to the FVC (3
1), the output voltage is supplied to the horizontal oscillation circuit (12), the horizontal oscillation frequency is switched to approximately 15.75 Kb, and this FVC (31) is supplied to the horizontal oscillation circuit (12).
The output voltage of step 1) is compared with the reference voltage in the comparison circuit (81), and the comparison output of the comparison circuit (81) causes the light emitting diode (85) to emit light, indicating "normal image input".
"Normal" is displayed in the normal display section (87) on the front panel (87).
8). Furthermore, when receiving a high-resolution computer monitor output with a horizontal frequency of about 24KH2, a horizontal synchronization signal with a horizontal frequency of about 24KHz is supplied from the synchronization separation circuit (7) to the FVC (31), and the FVC
(31) The output voltage of FVC (31) is supplied to the horizontal oscillation circuit (12), the horizontal oscillation frequency is switched to approximately 24KIIz, and the output voltage of this FVC (31) is supplied to the comparison circuit (81).
The comparison output of the comparison circuit (81) causes the light emitting diode (86) to emit light, and "high scan" indicating high resolution input is displayed on the front panel (87).
is displayed on the high scan display section (88).

Therefore, if you are receiving a normal image input signal thinking that it is a high-resolution human input signal due to a misunderstanding or misconception, or if you mistakenly think that the i-device is malfunctioning or there is a connection error due to the apparent low resolution of the image, By displaying "Normal" on the normal display section (88) of the front panel (87), it is possible to prevent confusion due to misunderstandings or misconceptions on the part of the user.

As described above, according to the multi-scan television receiver of this example, in the multi-scan television receiver that receives video signals of different horizontal frequencies, the mode detection circuit (11 ) is provided, and the detection output of this mode detection circuit (11) switches the horizontal oscillation frequency, and the detection output of the mode detection circuit (11) indicates that the horizontal frequency of the input signal is higher than a predetermined frequency. Discrimination means (81) (82) are provided to distinguish between resolution input and normal image input when the horizontal frequency of the input signal is lower than a predetermined frequency. Or display means (83) (8) for displaying normal image input.
4) Since (85) and (86) are operated, there is an advantage that confusion due to differences in horizontal frequencies can be prevented even when various devices outputting signals with different horizontal frequencies are switched and used.

It goes without saying that the present invention is not limited to the above-described embodiments, and can take various other configurations without departing from the gist of the present invention.

〔Effect of the invention〕

According to the multi-scanning television receiver of the present invention, in a television receiver that receives video signals of different horizontal frequencies, a detection circuit for detecting the horizontal frequency of the input signal is provided, and the detection output of this detection circuit allows the horizontal When the oscillation frequency is switched and the horizontal frequency of the input signal is higher than a predetermined frequency according to the detection output of the detection circuit,
Discrimination means is provided to distinguish between normal image input when the horizontal frequency of the input signal is lower than a predetermined frequency, and this discrimination means operates a display means for displaying high resolution input or normal image input. Therefore, even if various devices that output signals with different horizontal frequencies are switched and used, there is an advantage that confusion due to differences in horizontal frequencies can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the essential parts of the multi-scanning television receiver of the present invention, FIG. 2 is a route map for explaining the ff11 diagram, and FIG. 3 is a block diagram showing an embodiment of the multi-scanning television receiver of the present invention. FIG. 4 is a block diagram showing an example of the horizontal deflection system shown in FIG. 3, and FIG. 5 is a block diagram showing the vertical deflection system shown in FIG. 3. (1), (205) and (21S) are input terminals, (7) is a synchronous separation circuit, (11) is a mode detection circuit,
(12) is a horizontal oscillation circuit, (31) is a frequency-voltage conversion circuit, (81) is a comparison circuit, (82) is a reference voltage source, (
83) is a drive circuit, (84) is an inverter circuit, (85)
) and (86) are light emitting diodes, (88) and (89
) are a normal display section and a high scan display section.

Claims (1)

[Claims] In a multi-scan television receiver that receives video signals of different horizontal frequencies, a detection circuit for detecting the horizontal frequency of the input signal is provided, and the horizontal oscillation frequency is switched according to the detection output of the detection circuit, and the detection circuit of the detection circuit switches the horizontal oscillation frequency. Discrimination means is provided for identifying from the output a high resolution input when the horizontal frequency of the input signal is higher than a predetermined frequency, and a normal image input when the horizontal frequency of the input signal is lower than the predetermined frequency. A multi-scan television receiver, characterized in that the identification means operates a display means for displaying the time of high resolution input or the time of normal image input.