KR19990000718A - Monitor image processing circuit - Google Patents

Abstract

The present invention relates to an image processing circuit of a monitor, comprising: a computer main body comprising a first video processor, a video output circuit, and a mode discrimination circuit to output an image signal, and output a mode signal of the output image signal; And a second video processor, a horizontal deflection element, a power switching circuit, an image output circuit, and a CRT, which receive associative signals and mode signals output from the computer main body, and amplify levels of the image signals by the mode signals. It consists of a monitor that processes video signals by adjusting.

In particular, the present invention has the effect of increasing the image gain on the monitor and preventing saturation at the same time so that a bright image can be felt.

Description

Image Processing Circuit of Monitor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing circuit of a monitor, wherein a monitor capable of reproducing an image with the same brightness as that of a TV in a computer monitor when receiving a TV signal or reproducing an image signal through an M-pack card using a computer A video signal processing circuit.

Computer monitors and TVs are both used to display image data, but computer monitors have been developed for character display and graphics processing, and TVs have been developed for moving image processing. Therefore, the image adjustment specification is set high in the TV. In addition, TVs brighten the background screen and increase the gain of the image to process the image brightly, while a computer monitor processes the image in such a manner as to emphasize the image part by darkening the background screen.

For the same reason as above, when receiving a TV signal using a monitor of a computer or reproducing an image signal through an M-Pak card, the image appears dark. In order to solve this problem, the luminance and the image gain are forcibly adjusted. In this case, the image appearing through the CRT causes a saturation phenomenon, which causes the screen to spread.

The present invention is to solve the above problems, when using the TV card or M-pack card in the main body of the computer outputs the mode signal to the monitor, the monitor receives the mode signal output from the computer main body to the image circuit It is an object of the present invention to provide a monitor image processing circuit for switching gain in a configured amplifier circuit and switching a power supply voltage used in the image output circuit.

An image processing circuit of the monitor according to the present invention for achieving the above object comprises: a computer body for outputting an image signal and outputting a mode signal of the output image signal; The monitor is configured to receive an associative signal and a mode signal output from the computer main body, and to adjust an amplification level of the video signal based on the mode signal to process the video signal.

The computer main body may include a first video processor that receives a luminance signal from the received TV signal and a VTR signal, performs image processing, and outputs the video signal, and a video output connected to an output terminal of the first video processor. And a mode discrimination circuit which receives the luminance signal and discriminates the mode of the video signal and outputs the mode signal.

In addition, the monitor is connected to the output terminal of the video output circuit of the computer main body, the second video processor for receiving the video signal output from the video output circuit to separate and output the color signal, and the reference frequency signal inside the monitor A horizontal deflection element for generating a; A power switching circuit connected to the mode discrimination circuit of the computer main body and the output terminal of the horizontal deflection element, and switching power supplied to the system by a mode signal outputted from the mode discrimination circuit of the computer main body; Connected to an output terminal of the mode discrimination circuit of the computer main body, the second video processor and the power switching circuit, and outputted from the mode discrimination circuit of the computer main body by a mode signal and a power source supplied from the power switching circuit. An image output circuit for changing and outputting a gain of each color signal to be output; And a CRT connected to an output terminal of the image output circuit to display an image signal output from the image output circuit.

The present invention as described above is to determine the mode by receiving the luminance signal from the mode discrimination circuit of the computer main body, if the mode signal according to the determination result is applied to the image output circuit and the power switching circuit of the monitor, the mode discrimination circuit in the power switching circuit The power source is applied to the image output circuit by switching the power applied to the system by the mode signal applied from the second video processor, and the second video processor according to the mode signal applied from the mode discrimination circuit and the amount of power applied from the power switching circuit. Amplify and output each color signal output from.

The present invention as described above has the effect of increasing the image gain on the monitor and at the same time preventing saturation phenomenon so that a bright image can be felt.

1 is a circuit diagram showing the configuration of an image processing circuit of the present invention;

2 is an output waveform diagram of a monitor image processing circuit of the present invention;

Figure 3 is a waveform diagram of each part of the monitor image processing circuit of the present invention.

* Description of the symbols for the main parts of the drawings *

10 computer main body 20 monitor

11 video output circuit 12 first video processor

13 mode discrimination circuit 21 second video processor

22: horizontal deflection element 23: video output circuit

24: power supply switching circuit 23-1, 23-2, 23-3: amplifier

23-4: Amplification level controller 24-1: Voltage regulator

24-2: comparators R1, R5, R9: first output resistance

R2, R6, R10: second output resistance

R3, R4, R7, R8, R11, R12: Amplification Level Adjusting Resistance

R13: input resistor R14, R15: voltage regulating resistor

Q1, Q3, Q5: first transistor Q2, Q4, Q6: second transistor

SW1: first switch SW2, SW3, SW4: second switch

FET: Field effect transistor L: Output reactance

C: output capacitor

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

EXAMPLE

1 is a circuit diagram showing an embodiment of a monitor image processing circuit configuration according to the present invention, comprising: a computer body for outputting an image signal and outputting a mode signal of the output image signal; The monitor 20 is configured to receive the associative signal and the mode signal output from the computer main body 10, and to adjust the amplification level of the image signal by the mode signal to process the image signal.

In addition, the computer main body 10 includes a first video processor 12 which receives a luminance signal from the received TV signal and the VTR signal, performs image processing and outputs the same, and outputs the first video processor 12 to an output terminal of the first video processor 12. A video output circuit 11 connected to output a video signal and a mode discrimination circuit 13 for receiving a luminance signal to discriminate the mode of the video signal and output a mode signal.

In addition, the monitor 20 is connected to the output terminal of the video output circuit 11 of the computer main body 10, and receives the video signal output from the video output circuit 11 to output the separated color signal Two video processors 21; A horizontal deflection element 22 generating a reference frequency signal inside the monitor 20; It is connected to the mode discrimination circuit 13 of the computer main body 10 and the output terminal of the horizontal deflection element 22, and is supplied to the system by the mode signal output from the mode discrimination circuit 13 of the computer main body 10. A power switching circuit 24 for switching power; A mode which is connected to the mode discrimination circuit 13 of the computer main body 10 and the output terminal of the second video processor 21 and the power switching circuit 24 and output from the mode discrimination circuit 13 of the computer main body 10. An image output circuit 23 for varying and outputting the gain of each color signal output from the second video processor 21 by the signal and the power supplied from the power supply switching circuit 24; It is made of a CRT connected to an output terminal of the image output circuit 23 to display an image signal output from the image output circuit 23.

In the above, the power supply switching circuit 24 adjusts the external voltage value applied to the comparator 24-2 to be described below by the mode signal applied from the mode discrimination circuit 13 of the computer main body 10. (24-1); A comparator 24-2 for comparing the reference voltage generated inside the monitor 20 with a voltage value applied from the outside and controlling the output voltage value as a result value; An input resistor (R13) connected to the input of the comparator (24-2) to apply a voltage applied from the outside to the comparator (24-2); A voltage regulating resistor connected to the ground in parallel with the input resistor R13 at an input terminal of the comparator 24-2 and having a predetermined resistor connected in series to adjust a voltage value applied to the comparator 24-2 from the outside. (R14, R15); It is connected in parallel with a resistor connected to the ground among the predetermined voltage regulating resistors R14 and R15, and is turned on / off by the control of the voltage regulator 24-1 to set the predetermined voltage regulating resistors R14 and R15. A first switch SW1 for adjusting the voltage value applied to the comparator 24-2 by adjusting the? The field side is connected to the output terminal of the comparator 24-2, the collector side is connected to an external power supply terminal, and is turned on / off by the output terminal of the comparator 24-2 to adjust the output voltage value. A transistor (FET); An output reactance L connected to an emitter side of the field effect transistor FET and a power supply terminal of the image output circuit 23 to output a power value switched by on / off of the field effect transistor FET; Wow; One side is connected in parallel with the output reactance L to the power supply terminal of the image output circuit 23, one side is connected to the ground, and outputs a power value switched by on / off of the field effect transistor (FET). It consists of an output capacitor (C).

The image output circuit 23 includes a first amplifier 23-1, a second amplifier 23-2 for amplifying a level of each color signal output from the second video processor 21, A third amplifier 23-3 and an amplification level control unit 23-4 for controlling the signal amplification levels in the respective amplification units 23-1, 23-2, and 23-3.

In each of the amplifiers 23-1, 23-2, and 23-3, a predetermined amplification level adjusting resistor R3 having a base side connected to an output terminal of the second video processor 21 and an emitter side connected in series. Is connected to ground by R4, R7, R8, R11, and R12, and the collector side is connected to the emitter side of the second transistors Q2, Q4 and Q6 for signal output, so that the second video processor 21 First transistors Q1, Q3, and Q5 that receive an output signal; The base side is connected to the output terminal of the power supply switching circuit 24 via the first output resistors R1, R5, R9, and the emitter side is connected to the collector side of the first transistors Q1, Q3, Q5, and the collector The side is commonly connected to the output terminal of the power switching circuit 24 and the signal input terminal of the CRT via the second output resistors R2, R6, and R10, and amplifies the signal input from the second video processor 21 to the CRT. Applying second transistors (Q2, Q4, Q6); First output resistors (R1, R5, R9) for applying the output signal of the power supply switching circuit (24) to the base side of the second transistors (Q2, Q4, Q6); The connecting portion of the power supply switching circuit 24 is connected in parallel with the first output resistors R1, R5, and R9, and the connecting portion of the second transistors Q2, Q4, Q6 is connected in parallel with the signal input terminal of the CRT. Second output resistors R2, R6, and R10 for applying the output signal of the power supply switching circuit 24 to the collector side of the second transistors Q2, Q4 and Q6; Signal amplification levels in the amplifiers 23-1, 23-2, and 23-3 connected in series to the emitter side of the first transistors Q1, Q3, and Q5 under the control of the amplifier level controller 23-4. Predetermined amplification level adjusting resistors (R3, R4, R7, R8, R11, R12) for adjusting the voltage; The predetermined amplification level adjusting resistors R3, R4, R7, R8, R11, and R12 are connected in parallel with a resistor connected to ground, and are turned on / off by the control of the amplifying level control unit 23-4, A second switch for adjusting the signal amplification level in the amplifying sections 23-1, 23-2, and 23-3 by adjusting the amplification level adjusting resistors R3, R4, R7, R8, R11, and R12 (SW2, SW3, SW4).

According to the present invention as described above, the mode discrimination circuit 13 of the computer main body 10 receives the luminance signal to discriminate the mode, and the mode signal according to the determination result is switched to the image output circuit 23 of the monitor 20 and the power supply. When applied to the circuit 24, the first video processor 12 receives the luminance signal, performs image processing and applies the video output circuit 11, the video output circuit 11, the first video processor 12 Receives the video signal output from the output to the second video processor 21 of the monitor 20, the second video processor 21 outputs the video signal output from the video output circuit 11 of the computer main body 10 Each color signal is received and output to the image output circuit 23. The power switching circuit 24 switches the power applied to the system by the mode signal applied from the mode discrimination circuit 13 to output the image output circuit ( 23 to the image output circuit 23 And outputs the amplified signal for each color outputted from the second video processor 21 in accordance with the amount of power applied from the mode determination circuit and a mode signal applied at 13, the power switching circuit 24.

The output signal output from the image output circuit 23 and applied to the CRT is shown in FIG. 2, and in FIG. 2, A is an output waveform of the image output circuit 23 when the mode signal is a general PC signal. The output waveform of the video output circuit 23 when the mode signal is a TV card signal.

An operation when the mode signal is a TV card signal in the above operation will be described in detail with reference to FIG. 3.

If the luminance signal inputted to the computer main body 10 is a TV card signal such as the video input waveform B (①B) in Fig. 3, the mode discrimination circuit 13 of the computer main body 10 outputs a high signal and the high mode. The second switch SW2, SW3, SW4 is turned on by the signal, and the amplification level adjustment resistors R3, R4, R7, R8, R11, R12 connected in parallel with the second switch SW2, SW3, SW4 are short-circuited. As a result, the amplification levels in the amplifying units 23-1, 23-2, and 23-3 are increased in the image output circuit 23, thereby outputting a high output image output signal as shown in FIG. do.

At this time, the high signal output from the mode discrimination circuit 13 of the computer main body 10 in order to prevent saturation caused by the high image output signal as shown in B of FIG. 2 in the image output circuit 23. The first switch SW1 is turned on by the mode signal of the signal, and the voltage regulating resistors R14 and R15 connected in parallel with the first switch SW1 are short-circuited and applied to the positive terminal of the comparator 24-2. The signal applied to ③B in FIG. 3 and the negative terminal of the comparator 24-2 becomes ④B in FIG. 3, whereby a waveform such as ⑤B in FIG. 3 is applied to the field effect transistor (FET) and output. 3B and a high power supply voltage waveform are generated through the reactance L and the output capacitor C, thereby supplying a high supply voltage to the image output circuit 23.

As described above, the present invention, in particular, when a mode signal is output to the monitor when a TV card or an M-pack card is used in the main body of the computer, the monitor receives the mode signal output from the main body of the amplifier configured in the image circuit By converting the gain in the circuit and the power supply voltage used in the video output circuit, the image gain in the monitor is increased and the saturation phenomenon is prevented, so that a bright image can be felt.

Claims (6)

A computer main body which outputs an image signal and outputs a mode signal of the output image signal; And a monitor configured to receive an associative signal and a mode signal output from the computer main body, and to adjust the amplification level of the image signal according to the mode signal to process the image signal. The apparatus of claim 1, wherein the computer main body comprises: a first video processor for receiving a luminance signal from the received TV signal and a VTR signal, performing image processing, and outputting the video signal; And a mode discrimination circuit which receives a video output circuit and a luminance signal to discriminate the mode of the video signal and output a mode signal. The monitor of claim 1, wherein the monitor is connected to an output terminal of a video output circuit of the computer main body, receives a video signal output from the video output circuit, and separates and outputs a color signal. A horizontal deflection element for generating a frequency signal; A power switching circuit connected to the mode discrimination circuit of the computer main body and the output terminal of the horizontal deflection element, and switching power supplied to the system by a mode signal outputted from the mode discrimination circuit of the computer main body; Connected to an output terminal of the mode discrimination circuit of the computer main body, the second video processor and the power switching circuit, and outputted from the mode discrimination circuit of the computer main body by a mode signal and a power source supplied from the power switching circuit. An image output circuit for changing and outputting a gain of each color signal to be output; And a CRT tube connected to an output terminal of the image output circuit to display an image signal output from the image output circuit. The power supply switching circuit of claim 3, further comprising: a voltage regulator for adjusting an external voltage value applied to a comparator, which will be described later, by a mode signal applied from a mode discrimination circuit of a computer main body; A comparator for comparing the reference voltage generated inside the monitor with a voltage value applied from the outside and controlling the output voltage value as a result value; An input resistor connected to an input terminal of the comparator for applying a voltage applied from the outside to the comparator; A voltage adjusting resistor connected to the ground in parallel with an input resistor at an input terminal of the comparator and having a predetermined resistor connected in series to adjust a voltage value applied to the comparator from the outside; A parallel connection with a resistor connected to the ground of the predetermined voltage regulating resistor, and on / off by the control of the voltage regulator to adjust the voltage value applied to the comparator by adjusting the predetermined voltage regulating resistor value. 1 switch; A field effect transistor having a base side connected to an output end of the comparator, a collector side connected to an external power supply end, and turned on / off by an output end of the comparator to adjust an output voltage value; An output reactance connected to the emitter side of the field effect transistor and the power supply terminal of the image output circuit and outputting a power value switched by on / off of the field effect transistor; One side of the output reactance to the power supply terminal of the image output circuit; One end is connected in parallel with the output reactance to the power supply terminal of the image output circuit, one side is connected to the ground, characterized in that the output capacitor for outputting the power value switched by the on / off of the field effect transistor Image processing circuit of the monitor. 4. The image output circuit according to claim 3, wherein the image output circuit comprises: a first amplifier section, a second amplifier section, a third amplifier section, and an amplifier section for amplifying the level of each color signal output from the second video processor. And an amplification level control unit for controlling a signal amplification level. 6. The amplifier according to claim 5, wherein each of the amplifying sections is connected to the ground by a predetermined amplification level adjusting resistor having a base side connected to an output terminal of the second video processor, and an emitter side connected in series. A first transistor connected to the emitter side of the second transistor and receiving a signal output from the second video processor; The base side is connected to the output terminal of the power switching circuit through the first output resistor, the emitter side is connected to the collector side of the first transistor, and the collector side is connected to the output terminal of the power switching circuit and the CRT signal through the second output resistor. A second transistor commonly connected to an input terminal and configured to amplify the signal input from the second video processor and apply the amplified signal to the CRT; A first output resistor for applying an output signal of a power switching circuit to the base side of said second transistor; The connection portion of the power supply switching circuit is connected in parallel with the first output resistor, and the connection portion of the second transistor is connected in parallel with the signal input terminal of the CRT, and the output signal of the power switching circuit is connected to the collector side of the second transistor. A second output resistor applied to the; A predetermined amplification level adjustment resistor connected in series with the emitter side of the first transistor to adjust the signal amplification level in the amplification section under control of the amplification level control section; The signal amplification level in the amplifying section is adjusted by being connected in parallel with a resistor connected to ground among the predetermined amplifying level adjusting resistors, and on / off by the control of the amplifying level controlling section to adjust the predetermined amplification level adjusting resistor value. And a second switch to adjust the image processing circuit of the monitor.