KR19990069886A - Screen size control device according to viewing distance of TV - Google Patents

Abstract

The present invention relates to a screen size control apparatus according to a viewing distance of a television, and to an apparatus for automatically adjusting and outputting a size of a screen displayed on a CRT according to a viewing distance of a television. According to the present invention, a DC voltage according to a viewing distance sensed by a distance sensor mounted outside of a television system is converted into a digital data value by a signal conversion unit and applied to a microcomputer, and the microcomputer sets a predetermined reference voltage and a reference distance. After determining whether the viewing distance sensed by the distance sensor is far or near than the reference distance, and if the detected viewing distance is farther than the reference distance, deflection of the image signal executed by the deflection IC While applying the deflection variable control signal to increase the amount, when the detected viewing distance is closer than the reference distance, the image screen is enlarged by applying the deflection variable control signal to reduce the amount of deflection of the image signal executed by the deflection IC. Or by being reduced and outputted, without the need of manually manipulating the size of the video screen. It suggests a screen size control device according to the viewing distance of the television automatically adjusted according to the li.

Description

Screen size control device according to viewing distance of TV

The present invention relates to a screen size control apparatus according to a viewing distance of a television, and to an apparatus for automatically adjusting and outputting a size of a screen displayed on a CRT according to a viewing distance of a television.

In general, the adjustment of the size of the video screen displayed on the CRT of the television is made through a manual method, which will be described with reference to FIG. 1.

First, the high frequency signal received through the antenna 10 is converted into an intermediate frequency signal that is easily amplified by the tuner unit 15, and then amplified through the IF amplifier 20 and output to the image detector 25. The image detector 25 extracts an image signal of a high frequency signal and outputs the image signal to the main IC 30. In addition, the main IC 30 performs color demodulation and processing on the image signal applied from the image detector 25 to output the deflection IC 35, and the deflection IC 35 is applied from the main IC 30. The deflection amount of the video signal to be adjusted is output to the CRT 45 through the CRT driver 40.

At this time, when the user manipulates and enlarges an image enlargement button (not shown) provided in the remote controller 55 in order to change the size of the image screen output to the CRT 45, the microcomputer 50 to detect this. While the screen is enlarged by applying a control signal to increase the amount of deflection to the deflection IC 35, when the image reduction button (not shown) is operated to reduce the deflection IC 35, the microcomputer 50 that detects the deflection IC likewise deflects. A control signal for reducing the amount of deflection is applied to the IC 35 to reduce the screen.

However, the method of changing the size of the video screen by manipulating the buttons provided in the remote controller as described above is inconvenient in operating the viewer to operate the buttons, and the viewing distance of the viewer is fixed because the size of the changing screen is fixed. There is a problem that can not be considered.

Accordingly, the present invention aims to solve these problems by focusing on the problems described above, and an object of the present invention is to detect a distance at which a viewer watches television and to automatically display the screen size according to the distance. To provide a screen size control device according to the viewing distance of the television.

The technical idea of the present invention for achieving the object of the present invention is that the viewing distance of the viewer watching the television is sensed by the distance sensing means and a corresponding DC voltage value is generated and applied to the signal conversion means, the signal conversion The means digitally converts the DC voltage value and applies it to the control means. The control means determines whether the distance is farther or closer than the reference distance in comparison with the preset reference voltage data, and then different deflections in each case. By applying the variable control signal to the deflection means, the size of the video screen according to the viewing distance of the viewer is automatically adjusted and output.

1 is a block diagram showing an apparatus for enlarging a conventional video screen.

Figure 2 is a block diagram showing a screen size control apparatus according to the viewing distance of the television according to the present invention.

3 is a flowchart illustrating a screen size control apparatus according to a viewing distance of a television of the present invention.

<Description of the symbols for the main parts of the drawings>

10, 100: antenna 15, 150: tuner portion

20, 200: IF amplifier 25, 250: image detector

30, 300: Main IC 35, 350: Deflection IC

40, 400: CRT drive part 45, 450: CRT

50, 650: Micom 151: high frequency amplifier

152: mixing unit 153: local oscillation unit

500: VDC IC 550: distance sensor

600: signal conversion unit

Hereinafter, with reference to the accompanying drawings will be described a specific embodiment for achieving the above object of the present invention.

2 is a block diagram showing a screen size control apparatus according to a viewing distance of a television according to the present invention.

Referring to FIG. 2, the present invention provides a high frequency amplification unit 151 for amplifying a high frequency signal, which is a complex video signal received from an antenna 100, an input signal amplified by the high frequency amplification unit 151, and a local oscillation unit ( A tuner unit 150 including a mixing unit 152 for receiving a local oscillation frequency from the 153 and converting it into an intermediate frequency, and a local oscillating unit 153 for supplying a signal for frequency conversion to the mixing unit 152; An IF amplification unit 200 for intermediately amplifying the composite video signal applied from the tuner unit 150;

The image detector 250 extracts an image signal from the composite image signal applied by the intermediate frequency amplification from the IF amplifier 200 and the image signal output from the image detector 250 is subjected to luminance and color demodulation processing. And a deflection IC 350 for adjusting the deflection amount of the video signal processed by the main IC 300 and outputting the deflection IC 350 to the CRT driver 400 and the deflection IC 350. A CRT driver 400 for receiving the adjusted video signal and displaying the same on the CRT 450;

A distance sensor 550 for detecting a viewing distance of a viewer watching a television, a signal converter 600 for digitally converting a signal applied from the distance sensor 550, and the signal converter 600 A microcomputer 650 for applying a deflection data control signal to the deflection IC 350 based on the digitally converted signal, and a VCD IC for detecting a vertical frequency of a video signal output from the tuner unit 150 (VIDEO CHROMA DEFLECTION). IC;

Hereinafter will be described in detail the operation according to an embodiment of the present invention made as described above.

First, the high frequency signal, which is a broadcast signal received from the antenna 100 of the television, matches the characteristic impedance of the supply line FEEDER with the input impedance of the high frequency amplifier 151 through an input circuit (not shown) of the tuner unit 150. The high frequency amplifying unit 151 is output to the high frequency amplifying unit 151, and the high frequency amplifying unit 151 increases the gain of the received high frequency signal, improves selectivity, and prevents image disturbance.

In addition, the signal amplified by the high frequency amplifier 151 and the frequency output from the local oscillator 153 are input to the mixer 152, the mixer 152 mixes the high frequency signal and the local oscillation frequency To generate an intermediate frequency corresponding to the difference between the two frequencies.

In addition, the intermediate frequency signal output from the tuner 150 is amplified by the IF amplifier 200 and then output to the image detector 250, and the image signal by the image detector 250. After the bay is detected, it is output to the main IC 300 connected to the rear stage. In addition, the main IC 300 separates the color signal (C signal) and the luminance signal (Y signal) mixed in the video signal, synthesizes the burst signal, and detects and amplifies the color difference signal (RY, BY). The video signal as the primary color signal is output.

Here, the distance sensor 550 mounted on the system of the television detects the separation distance between the viewer and the television system, that is, the viewing distance, and generates a DC voltage value corresponding to the viewing distance as illustrated in the attached Table 1. The signal converter 600 is applied to the signal converter 600, and the signal converter 600 is converted into digital data that the microcomputer 650 can process and applied to the microcomputer 650.

Viewing distance DC voltage value 5M 5 V 4M 4V 3M 3 V 2M 2 V 1M 1 V

That is, as shown in Table 1 above, the reference distance and the reference voltage value for protecting eyesight of the viewer watching the television are set in advance, and the distance sensor 550 detects the viewing distance of the viewer. The corresponding DC voltage value is generated according to the sensed viewing distance.

The DC voltage value generated as described above is converted into a digital value through the signal converter 600 and applied to the microcomputer 650. The microcomputer 650 compares and discriminates the predetermined reference voltage value based on the digital value. After determining the viewing distance, the deflection IC of the deflection variable data of the video signal displayed on the CRT 450, that is, the data control signal for varying the horizontal position and size and the vertical position and size of the video screen on which the video signal is displayed. To 350.

Therefore, the deflection IC 350 deflects the deflection current and the deflection voltage according to the control signal of the microcomputer 650 so that the size of the video screen is changed and displayed according to the viewing distance.

The process of changing the size of the video screen will be described in more detail.

When the reference distance and the DC voltage value is set to 3M and 3V, respectively, when the distance sensor 550 detects the viewing distance to generate a DC voltage of 4V, the 4V DC voltage is converted into a signal converter. The control unit 600 converts the digital data value to the microcomputer 650 by applying the data to the microcomputer 650, and compares the microcomputer 650 with a reference voltage value to determine that the microcomputer 650 is farther from the reference distance. Apply a signal. That is, the deflection variable data for increasing the vertical position and size of the video screen and the horizontal position and size are applied to the deflection IC 350.

On the other hand, when the DC voltage value generated by the distance sensor 550 is smaller than the reference voltage value, the microcomputer 650 detects that the viewing distance of the viewer is closer than the reference distance and adjusts the deflection amount of the video signal. The control signal for reducing is applied, and an overscan screen is displayed on the blank portion of the surrounding screen caused by the reduction of the amount of deflection, thereby preventing discomfort in viewing.

On the other hand, the VCD IC 500 connected to the tuner unit 150 detects when the vertical frequency of the image signal received from the antenna 100 is different from the frequency applied to the system, and detects it by the deflection IC 350. By applying a signal, a deflection operation corresponding to a vertically received vertical frequency is performed.

This is because the deflection IC 350 does not have a function of distinguishing the received vertical frequency, and when the vertical frequency is distorted, that is, when a vertical frequency smaller than the vertical frequency applied to the system is received, the image displayed on the CRT 450 is displayed. This is because the vertical size of the screen is increased and a good screen is not displayed.

3 is a flowchart illustrating a screen size control apparatus according to a viewing distance of a television according to the present invention, in which the power supply of the television is switched on (S10) and the power supply switching step (S10). After the power of the television is switched on, a channel is tuned and a broadcast program output step (S20) for outputting a corresponding broadcast program, and the sensor for determining whether the operation mode of the distance sensor 550 in the broadcast program output step (S20). Operation mode determination step (S30),

In the operation mode of the distance detection sensor 550 in the sensor operation mode determination step (S30), the distance detection step (S40) and the DC voltage applied through the distance detection step (S40) for detecting the viewing distance of the viewer A DC voltage discrimination step (S50) discriminated from the reference voltage, and a deflection adjustment step (S60) in which the deflection adjustment of the video signal is performed in response to the viewing distance according to the DC voltage value determined in the DC voltage discrimination step (S50); An output step (S70) of outputting a video screen adjusted by the deflection control step (S60);

When the sensor operation mode determination step (S30) is not the operation mode of the distance sensor, the broadcast program output step (S20) that continues to output the previous broadcast program, and the DC voltage determination step in the DC voltage determination step (S50) If not, the distance detection process by the distance sensor 550 is performed in the distance detection step (S40) that is repeatedly executed.

Hereinafter, an operation after the distance detecting step S40 will be described with reference to the accompanying drawings.

First, the viewing distance of the viewer is detected by the distance sensor 550 mounted on the outside of the television system to generate a DC voltage corresponding to the detected viewing distance, and then through digital conversion of the signal conversion unit 600. It is applied to the microcomputer 650. In addition, the microcomputer 650 compares the digital data value applied by the signal converter 600 with data of a preset reference voltage value, and the viewing distance detected by the distance sensor 550 is farther than the reference distance. To determine whether it is close or close.

The microcomputer 650, which has performed the DC voltage determination process as described above, applies a control signal for changing the amount of deflection of the video signal generated by the deflection IC 350 according to the determination result. In response to the control signal of the microcomputer 650, an image screen on which the deflection output is adjusted is displayed.

As described above, in the present invention, a DC voltage according to a viewing distance sensed by a distance sensor mounted outside of a television system is converted into a digital data value by a signal converter and applied to a microcomputer, and the microcomputer is set in advance. Based on the reference voltage and the reference distance, the distance detecting sensor detects whether the viewing distance is farther or closer than the reference distance, and if the detected viewing distance is farther than the reference distance, the deflection IC is executed. While applying the deflection variable control signal to increase the amount of deflection of the video signal, if the sensed viewing distance is closer than the reference distance by applying a deflection variable control signal to reduce the amount of deflection of the video signal executed by the deflection IC It is necessary to manually manipulate the size of the video screen by enlarging or reducing the video screen. There is an effect that is automatically adjusted in accordance with the viewing distance of the viewer.

Claims (2)

In the television that automatically adjusts the size of the video screen according to the viewing distance of the viewer, Distance sensing means for sensing a viewing distance of viewers watching the television; Signal conversion means for digitally converting the DC voltage value output from the distance sensing means; A control means for receiving a digitally converted DC voltage value from the signal converting means and comparing the predetermined reference voltage data and the reference distance data to apply different deflection variable control signals; And deflecting means for varying the amount of deflection of the video signal displayed on the screen of the television according to the deflection variable control signal of the control means and outputting the deflection means according to the viewing distance of the television. The method of claim 1, wherein the control means compares the DC voltage value converted into the digital data value by the signal converting means with a preset reference voltage data to determine a deflection amount of the deflection means. While increasing the deflection variable control signal, if the distance is closer than the reference distance is applied to the deflection variable control signal for reducing the amount of deflection of the deflection means, the surrounding screen generated by the decrease of the deflection amount Screen size control device according to the viewing distance of the television, characterized in that the over-scan (OVER SCAN) screen is displayed in the blank portion of the television.