JPS58218275A - Television receiver - Google Patents

Abstract

PURPOSE:To obtain a high-resolution picture quality, by producing a pseudo signal from a signal data between scanning lines when converting a standard system television signal to a horizontal scan frequency signal of (n) times. CONSTITUTION:A radio wave from a broadcasting station is received by an antenna 1, demodulated to a signal corresponding to a three primary colors by a demodulation circuit 3 and supplied to a signal converting circuit 4. The signal converting circuit 4 produces a pseudo video signal from a standard system television signal from data between scanning lines. The signal is converted to a television signal having a horizontal scan frequency of 2 times and supplied to a video amplifying circuit 5 to drive an image receiving tube 16. Thereafter, a horizontal synchronizing signal separated from a synchronous separation circuit 6 is supplied to a PLL circuit 8 to generate a clock signal of a signal converting circuit 4. At the same time, the horizontal synchronizing signal is converted its frequency to a horizontal synchronizing signal having a frequency of 2 times and supplied to a horizontal deflection circuit 9 to drive a horizontal deflection coil.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a television receiver that uses a storage element to convert a standard television signal into a signal having a horizontal scanning frequency that is n times higher for display.

The current standard television system is NTSO.

There are methods such as PAL and SICAM, but the resolution of none of them is necessarily sufficient. Especially today, when there is a demand for larger screens, there is a demand for higher resolution broadcasting. Therefore, in the near future, it is thought that high-definition broadcasting will be implemented with the number of scanning lines 2 to 3 times that of the current standard system and the band width 6 to 10 times. 1126 lines, 20 &, RX A in the luminance signal band
(Electronic 1ndu8tri, ELLM ggocation: Electronic Industries Association) has 1023 scanning lines, 21.1 total in the luminance signal band, BBC
proposed various systems with a scanning line count of 1601 and 50 in the luminance signal band. During the transitional period of commercialization of these new television systems, it is necessary to develop so-called compatible television receivers so that the receivers that receive the signals of these systems can also receive the standard television signals. It is believed that if this is realized, the spread will be faster.

In addition, in the recent information age, there is an increasing demand for character displays that display alphanumeric characters and characters, and graph ink displays that display charts, patterns, etc. as computer terminals. In order to improve the amount of information, these devices have increased the resolution and number of scanning lines, and the scanning frequency has been set to about twice that of the standard television system. . These display devices also receive standard television signals□.

If configured in such a way that signals from VTRs and cameras can be received, the scope of application of the display device will expand, and there are great expectations for its realization.

In order to create a compatible television receiver, both the standard system and the new system must share circuits, not only for the signal circuit, but also for the deflection circuit, due to the large difference in horizontal scanning frequency. It is difficult to change the switch! It was necessary to switch the circuit using a relay or the like to operate it. This not only made the circuit more complex, but also caused problems in terms of reliability since parts with high potential were switched. Also, conventionally used devices for converting between systems with different scanning frequencies are:
Since the conversion method was to exactly match the scanning frequency to be converted, operations such as dropping or adding one signal for every several scanning lines were required, and the configuration was difficult. It was very □ complicated.

For this reason, a method was proposed in which the standard television signal is converted into a signal having a horizontal scanning frequency close to the horizontal scanning frequency of the new television system and displayed.
d':, was proposed in No. 141201.

However, in the same application, when a standard format television signal is converted into a signal having a horizontal scanning frequency close to n times using a storage element, the same data = 2n times the speed of the standard format television signal in. Since it is read out twice, it has the disadvantage that it is difficult to improve the image quality by increasing the number of scanning lines.

Therefore, in view of the above points, the present invention creates a pseudo signal from signal data between scanning lines with a simple circuit configuration, thereby making it possible to display a screen with high resolution and image quality on a television. The purpose is to obtain a John image receiving machine.

EMBODIMENT OF THE INVENTION Hereinafter, the present invention will be described in detail with reference to the drawings showing one embodiment thereof.

FIG. 1 is a block diagram showing the overall configuration of a receiver according to an embodiment of the present invention, and FIG. 2 is a waveform diagram for explaining the signal conversion operation thereof. In this example, i n
The case where = 2 will be described.

Radio waves emitted from a broadcasting station are received by an antenna 1, converted to an intermediate frequency by a television tuner 2, amplified, and then detected to become a composite video signal.

This composite video signal is supplied to the demodulation circuit 3.
A signal corresponding to the three primary colors, C, for example R, G.

The signal is demodulated into a B signal, or a Y, I, or Q signal, and then supplied to a signal conversion circuit 4. In the signal conversion circuit 4,
A pseudo-video signal is created from the data between the scanning lines from the standard television signal shown in Figure 2a, and the signal is converted into a television signal with twice the horizontal scanning frequency as shown in Figure 2. n1 is supplied to the video amplification circuit 6. Then, the image is amplified by the video amplification circuit 6 and the picture tube 16 is driven.

Next, the synchronization separation circuit 6 separates the horizontal synchronization signal and the vertical synchronization signal from the synchronization signal obtained by the demodulation circuit 3. The vertical synchronization signal is supplied to the vertical deviation circuit 7.n1 Vertical deviation circuit 7
At the same time, the vertical deflection coil of the deflection yoke 15 is driven.

A horizontal synchronizing signal (dPLL (phase-locked loop)) circuit 8 is supplied with the horizontal synchronizing signal (dPLL).The clock signal for the signal conversion circuit 4 is generated in the PLL circuit 8. The horizontal synchronizing signal converted to twice the frequency is supplied to the horizontal deflection circuit 9.
The horizontal deflection coil of the deflection yoke 16 is driven by the horizontal deflection circuit 9Vc.

In order to display the called pseudo-interlaced image, the PLL circuit 8 outputs auxiliary deflection pulses with a duty cycle of 60 inches in a standard horizontal scanning period. The auxiliary deflection pulse is supplied to the auxiliary deflection circuit 1o, and the auxiliary deflection circuit 10 drives the auxiliary coil 12.

As described above, the standard video signal is displayed after signal conversion and scanning frequency conversion.

Next, we will discuss the signal conversion circuit 4, which is a feature of this device, in the third section.
This will be explained in detail using the block diagram shown in the figure.

The signal conversion circuit 4 includes a signal conversion circuit 1 for converting a standard television signal into a signal having a horizontal scanning frequency twice that of the standard television signal. ．． ．． .

A means is required. For this purpose, we will line up:・
As a thick memory element, for example, 712. Logline memory charge coupled devices (caD) and packet brigade devices (BBD) are useful.

Recently, high-speed versions of COD have been announced.

Input/output stage low-pass filter 14.34U signal frequency band f. /2 (fC: clock frequency), and is a low-pass filter for smoothing clock spikes and the like to make a continuous analog signal. After being amplified by an amplifier 16, it is sent to a line memory 16.17 such as a COD. supplied n
Ru. C from the PLL circuit 8 (clock pulse [C
It drives CjD16.17 and performs signal conversion. This 0GD1e.

17 output 1d (r by two delay circuits 20, 22, 21.23 connected in series to each 3CD 16.17)
) IH/2CH: Delayed by a time of 'one standard horizontal period).

The signal conversion outputs from the CCDs 1e and 17 and the signal conversion outputs processed by the delay circuits 23 and 21 are added to the adder circuit 25.
j 24 consoles"gO count, pseudo between scanning lines, '1:.

A typical video signal is created, the amplitude of which is controlled by gain control circuits 27 and 26, and supplied to gate circuits 30+29. Further, the signal conversion outputs from the delay circuits 20 and 22 are also supplied to the gate circuits 28 and 29, and only the signal conversion outputs for the necessary readout period are extracted, and the four signal conversion outputs are added together in the adder circuit 32. Ru.

Then, after being amplified by an amplifier 33, it is taken out as a continuous analog signal by a low-pass filter 34, and an n1 signal conversion output is obtained.

Next, the operation shown in FIG. 3 will be explained in detail using the waveform diagram shown in FIG. 4.

FIG. 4a shows a standard television signal obtained from the demodulation circuit 2 in FIG. , amplified, and then supplied to (3CD16.17).The write and read operations of CGD16.17 are shown in Figure 4. The operation is reversed every horizontal scanning period of the standard television signal.The written signal is set to operate during the next horizontal scanning period (
Reads out at twice the speed of writing. Therefore, the signal d is read out from the C0D16, the operation of which is shown in FIG. Also, the operation is shown in Fig. 4C.
The Karahagi signal is read out.

The analog line memory 16, 17 such as the CCD can be read out once, and in order to create a pseudo video signal between scanning lines, it is necessary to read out two more times. Therefore, C
The signal conversion output from 0D16.17 is the CGD16.1 mentioned above.
7 and two delay circuits connected in series 20.21
and 22. 23, the same data as the signal conversion output data of the CCDs 16 and 17 is read out twice with a delay of one half period <11> of one horizontal period of the standard method. Therefore, the delay circuit 2o outputs the signal shown in FIG.
They output a signal of 1.

Next, dedicated line - In order to create a pseudo video signal, the signal from the delay circuit 21 shown in Fig. 4 f and the CC signal shown in g
The signal from D17 is added in the adder circuit 24, and the signal is controlled to 1/2 in the gain control circuit 24, thereby creating a pseudo video signal between the scanning lines shown in FIG. ing.

Further, the signal from the delay circuit 23 shown in FIG. 4i and the signal from the CCD 16 shown in FIG. A pseudo video signal between the scanning lines shown in Figure 4k is created.
ing.

The signals from the gain control circuits 26, 27 and the delay circuits 20, 22 are supplied to the gate circuits 299, 30, and 28, 31, and only the signal conversion output of the necessary read period is extracted. Figure 4 1 [This gate circuit 29.30.28,
The four signal conversion outputs from 31 are summed by an adder circuit 32, and after being amplified by an amplifier 33, they are taken out as continuous analog signals by a low-pass filter 34. It is supplied to the amplifier circuit 6. The video amplification circuit 6 amplifies the picture tube', 2〒17. The converted signal is displayed on the screen.

In general, the basic theory of line memory elements, such as COD of analog line memories, is as follows, where:
B is the maximum circle that can be sampled. From the above, the number of bits (b) and clock frequency (f) of analog line memory such as COD in this device
O) is shown below.

CCD16.17 has 910 bits and is clocked by write clock φ5. φ, (sampling clock) is 'fsa
” 14/32 rhinoceros, read clock φ2゜φ
4 (transfer lock) is 8f8° = 28.6414-h
In addition, the above COD operation uses a clock with an opposite phase to sample the input signal every 1/2 cycle, doubling the sampling rate and performing operation in multiplex mode K11ll. However, the above and 5
11 It goes without saying that equivalent signal conversion can be performed.

Next, the interlace relationship will be explained with reference to FIG. 6, which shows the state of scanning lines on the screen. The numbers written in the figure indicate the numbers of the scanning lines, and the scanning lines of even and odd fields are indicated by solid lines and broken lines, respectively. In addition, the symbols (a), (b), (c), etc. in the diagram indicate the signals for each scanning line of the standard format television signal before signal conversion shown in Figure 5 B. It is hail;
Even and odd fields are distinguished by adding a ``''' to the symbol.

, after E conversion, the number of scanning lines is 060, and since it is an even number, interlaced scanning is not performed, and as shown in Figure 6,
The even field signal and the odd field signal overlap, making it impossible to reproduce a normal screen.

Means for realizing the scanning line appearance as shown in FIG. 5C will be explained using the waveform diagram in FIG. 6. Incidentally, in the scanning line numbers shown in FIG. 6C, an even scanning number indicates a pseudo signal line n which is pseudo-generated from signal data between scanning lines.

In Figure 6, a is the standard horizontal synchronization signal, b is 2
C is the standard horizontal scanning period output from the PLL circuit 8 in FIG. This is the auxiliary deflection signal waveform when the deflection pulse voltage is supplied to the auxiliary deflection circuit 1o in FIG. 1 and the auxiliary coil 12 is driven. The numbers written in the figure in d correspond to the numbers of the scanning lines shown in FIG. Moreover, the vertical deflection signal waveform is shown in e.

The relationship between the polarity of the auxiliary deflection pulse signal in FIG. Already set to the addition direction for the first scan line of the field.

The position of the (2m)th scanning line from Figure 6 d is (2m-1
)th scanning line and the original position of the (2m)th scanning line, and it can be seen that the original signal shown in FIG. 6a is faithfully reproduced.

The method for performing auxiliary deflection using an auxiliary coil has been described above, but the same method can be achieved by superimposing it on the vertical deflection current or using a magnetic field using a convergence coil.

Also, this implementation f! l't' has been described for the case of n-2, but the same applies to other cases.

As described above, according to the present invention, since a standard television signal is converted into a signal corresponding to a horizontal scanning frequency that is n times higher, it is easy to change the standard television broadcasting method. It is possible to obtain a television receiver that is compatible with displaying on a high-resolution television receiver that supports a horizontal scanning frequency that is approximately n times higher than that of a standard television signal. Therefore, a horizontal deflection circuit can be realized without switching in areas where the signal level is high, improving reliability, and since the signal converter simply converts the signal by n times, it can be realized with a simple configuration. . Furthermore, since a pseudo signal is created from signal data between scanning lines, high-resolution image quality can be obtained. i゛.

Furthermore, the auxiliary deflection means is set so that the position of the (2m)th scanning line is the midpoint between the (2m-1)th... scanning line and the original position of the (211)th scanning line. Because of this, the signal-converted negative signal and the pseudo signal created from the signal between the scanning lines are alternately scanned, resulting in relatively easy-to-see image quality.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a television receiver according to an embodiment of the present invention, FIG. 2 is a waveform diagram for explaining its operation, and FIG. 3 is a block diagram of a specific example of the circuit. FIG. 4 is a waveform diagram for explaining the operation, FIG. 6 is a schematic diagram showing the state of scanning lines on the screen, and FIG. 6 is a waveform diagram for explaining the operation. 3... Demodulation circuit, 4... Signal conversion circuit, 8... PLL circuit, 10... Auxiliary deflection circuit, 16 17......・COD, 20t 2
1, 22, 23... Delay circuit, 24, 25...
... Addition circuit, 26.27 ... Gain control circuit, 28, 29.301 31 ... Gate circuit, 32 ... Addition circuit. Name of agent: Ben-shi Toshio Nakao and one other person □. Taste Figure 6

Claims (1)

[Claims] Standard television signals are transmitted using memory circuits.
The signal is converted into a signal having a horizontal scanning frequency twice as high (n is an integer of 2 or more) and supplied to the cathode ray tube, and an auxiliary coil is used to perform auxiliary deflection to display a pseudo-interlaced image. □One horizontal period of semi-method
) and read it out at n times the speed of storage 2
a first #second memory circuit, each connected in series with the memory circuit and having a delay time of (-). Second
with a delay circuit of (tl+1
') signal converting means for repeatedly reading the signal; first pseudo-signal creating means for creating a pseudo-signal from the signal from the first delay circuit and the signal from the second memory circuit; a second pseudo signal creating means for creating a pseudo signal from the signal from the delay circuit and the signal from the first memory circuit; A television receiver comprising means for creating a signal conversion output signal using a pseudo signal from a second pseudo signal creation means and a signal from the 11M2 memory circuit.