Figure 1 shows a brightness regulation circuit a in the device also a display device is roughly block represents, Also indicative of the video preamplifier Figure 2 shows a the root control part is surface of Figure 1. * Description of the sign for major part * of the drawings 100: video card ' 200: microcomputer 300:400 signal processor-signal gain compensative: FBT 500: video preamplifier 510: number 1 amplification part 520: contrast control unit 530: preventing piracy and control part 550 540: number 2 amplification part: number 3 amplification part 570 560: number 4 amplification part: brightness control the signal controller supplies 580: clamp gate 590: blank gate 600: cathode ray tube Brightness of the device display device (Brightness) provided control circuit, more specifically video preamplifier (Pre Amplifier) a video signal input unit includes a plurality of is (Pedestal) pedestal and controlling brightness display device relates to brightness regulation circuit of. A monitor having a cathode ray tube generally display device in order to control the brightness of screen of display device disposed on the outside of a switch or volume input device or keyboard input commands into the controlling screen brightness through. for adjusting the. Screen brightness and and to regulate the contact point volume of adjustment or keyboard input commands into the controlling screen brightness through the movable member is driven by, grid voltage or cathode number 1 of electron gun for reference voltage from clamp level is parts is changed in a rule brightness of screen. I.e. cathode number 1 grid between the larger the voltage of the electrons from cathode material engages the brightness of screen are then reduced, and the structure, the smaller the voltage between grid number 1 cathode cathode from the amount and of an electron increases, and a brightness of the recording operation.. However, provided as a word line adjustment is brightness of screen of device display of the existing method and controlling brightness range is limited since the brightness of screen unit is adjusted to a specific. The video of the device thus layered and mixed light-emitting diode device for current of the video signal pedestal is by screen brightness the circumference can be adjusted and the brightness regulation circuit of a display device is provided to. To achieve this object in the device for R circuit for controlling brightness of a display according to an device, G and B video signal and horizontal/vertical synchronous signals to a computer system outputs a video recorder comprising the same card and, R from an output in an video card, video signal of B and G is pedestal and controlling brightness video preamplifier and, video preamplifier adjusting module of the response to a voltage samples the video signal in response to display a cathode ray cylinder head of characterized in that. Hereinafter, reference to drawing with an device for controlling brightness of display of the device. as further described circuit. Figure 1 shows a brightness regulation circuit a in the device also a display device is roughly. is a block represents. Drive the discharge lamp, microcomputer (200) a video recorder comprising the same card a computer system (100) a horizontal and a vertical synchronization signal is outputted from a reference outputs the oscillating signal. -signal gain compensative signal processor (300) has microcomputer (200) in the output from the reference oscillator signal and video card (100) a vertical/horizontal sync outputted from the high voltage circuit signal accepted from the simultaneous reproducing unit (not is shown) and the biasing circuit (not is shown) sending signals to.. FBT (400) the-signal gain compensative signal processor (300) is coupled to an output stage of order to control all operations (600) for producing a high pressure supplied to.. Video preamplifier (500) the video card (100) from an output in an R, video signal of B and G is pedestal and controlling brightness the cathode ray tube (600) supplied to. The above-mentioned also Figure 2 shows a the root control part is surface indicative of the video preamplifier of Figure 1. Drive the discharge lamp, number 1 amplification part (510) the video card the video signal accepted from the simultaneous reproducing unit amplification to. Is number 1 amplification part (510) in the reversal of terminal (-) 2.4V or not, thereby providing a desired video signal is inputted is voltage is input to the low bias. Preventing piracy and control part (530) user's input according to contrast control unit (520) for preventing piracy and control control signal number 1 amplification part according to (510) are amplified in the video adjusts the amplitude of this signal the intensity of an. Number 2 amplification part (510) according to control signal preventing piracy and control the light control part (530) the bits is adjusted a contrast and its regulating compared samples the video signal in response to brightness, the amplification. Is number 2 amplification part (540) has a non-reverse terminal (+) the preventing piracy and control part (530) which output of terminals connected to each other, shift terminal (-) the brightness control the signal controller supplies (570) is connected output terminal of. Number 3 amplification part (550) the number 2 amplification part (540) compared in, amplified video outputs the signal. Is number 3 amplification part (550) to the output terminal of transistor (Q) of control inducting layer are connected to a base terminal, a power source is attached to the collector of transistor (Q) terminal (Vcc) is provided, into the video signal is outputted at the VCR collector and a. Number 4 amplification part (560) the blank gate (590) is operated for adjusting the brightness when video signal, and feedback the. Brightness control the signal controller supplies (570) the number 4 amplification part (560) control voltage and brightness video input signals from the video signal pedestal compares a video level adjusting circuit number 2 amplifier (540) in the reversal of terminal (-) 1 and provides an output to. Is brightness control the signal controller supplies (570) in the reversal of terminal (-) the number 4 amplification part (560) off by output terminal of, non-inverting terminal (+) the brightness according to user's input control signal terminal is connected. In addition brightness control the signal controller supplies (570) to the holder, and an adjusting output terminal of for and which can continue the brightness, i.e. and therefore a DC component reproducing (DC Restoration) for constitution: a clamp capacitor terminals connected to each other. Clamp gate (580) has a brightness adjusting the signal controller supplies (570) to persist to time is operated. Blank gate (590) a power supply voltage is turned off when the video signal is by video signal outputs a relay driving signal. that do not output. During the above-mentioned of Figure 2 drawing code described is the resistance R1-R4 code name american opinion. Furthermore, the vibration sending and receiving members are brightness regulation circuit device of a display according to an in the device specifically for action of the described. First video card number 1 amplification part is the video signal (510) in the reversal of terminal (-) is input to a. amplified. Users is input at one end by handling the push switch or the like a contrast adjustment signal is contrast control unit (520) is input into, contrast control unit (520) in preventing piracy and control part (530) to preventing piracy and control control signal is outputted at the VCR. Thus preventing piracy and control part (530) in number 1 amplification part life pressure control according to control signal (510) are amplified in the video of an amplitude of a signal to capacitor. preferably small. Thus contrast is controlled video signal number 2 amplification part (540) has a non-reverse terminal (-) is input to a compared, . amplified. Number 2 amplification part (540) compared in, amplified video signal a number 3 amplification part (550) in turn through collector of transistor (Q) is amplified noise signal transmitted to the input terminal cathode ray tube (600) outputs the in. Furthermore, number 2 amplification part (540) compared in, amplified video signal a number 4 amplification part (560) is input into, number 4 amplification part (560) for brightness control in video signal, and feedback the. Number 4 amplification part (560) from video input signals brightness control the signal controller supplies (570) in the reversal of terminal (-) is input into, brightness control the signal controller supplies (570) has a non-reverse terminal (+) according to the user's input is signal is inputted for controlling brightness. Brightness control the signal controller supplies (570) in feedback video input signals and brightness control voltage compares the video signal pedestal a video level adjusting circuit number 2 amplifier (540) in the reversal of terminal (-) 1 and provides an output to. And brightness control the signal controller supplies (570) terminals connected to each other a clamp capacitor to the output terminal of the brightness control the signal controller supplies (570) modulated through for and which can continue the brightness, i.e. to a and therefore a DC component reproducing (DC Restoration). I.e. the video layered and mixed light-emitting diode (500) 70 in regulating the current of the video signal input in addition to pedestal is by cathode ray tube (600) of number 1 without control the voltage in grid variably brightness down by long-time use is formed inside the tie.. Here, in the device, as shown in Figure 2 of video signal R, G, palettized B one of brightness regulation circuit for described but, other than it also also color the same 2 is provided to obtain simultaneously the display. to co-operate. And third signal interrupting parts relatively to the device for controlling brightness of display of the device, so as to change a clamp level or cathode number 1 grid voltage without brightness directly from video free amp circuits to the simply structured since the decoration plate further comprises an over a wide range, of the brightness able to arrange.. Disclosure brightness video preamplifier adjusting circuit a video signal input unit includes a plurality of optical disk is pedestal by a rope.. A brightness regulation circuit a in the device R, G and B video signal and horizontal/vertical synchronous signals to a computer system outputs a video recorder comprising the same card and, R from an output in an video card, video signal of B and G is pedestal and controlling brightness video preamplifier and, video preamplifier adjusting module of the response to a voltage samples the video signal in response to display the cathode-ray tube, which consists of in. Therefore, the device circuit simply structured the decoration plate further comprises an over a wide range, of the brightness able to arrange.. R, G and B video signal and horizontal/vertical synchronous signals to a computer system outputs a video recorder comprising the same card; Said video card from an output in an R, video signal of B and G is pedestal and controlling brightness video preamplifier; and Said video preamplifier adjusting module of the response to a voltage samples the video signal in response to cylinder head of a cathode ray display characterized by display device to brightness regulation circuit of. According to Claim 1, said video preamplifier a; Video card the video signal accepted from the simultaneous reproducing unit amplication number 1 amplification part; Contrast control unit for preventing piracy and control control signal according to said number 1 video are amplified in the amplification part adjusts the amplitude of this signal the contrast of modulating preventing piracy and control part; According to control signal preventing piracy and control said said preventing piracy and control unit samples the video signal in response to controlled contrast compared, amplifying number 2 amplification part; Compared in amplification part said number 2, amplified video signal number 3 amplification part in case that the initial cathode ray tube; When it is off the supply voltage can be acquired by said gate blank for muting video signal; Said blank gate upon operation of the apparatus for adjusting the brightness video signal feedback for number 4 amplification part; and Said number 4 amplification part control voltage and brightness video input signals from the video signal pedestal compares the level adjusting a received radio signal, which outputs to the amplifier said number 2 brightness control the signal controller supplies is made of a magnetizing coil, characterized by display brightness regulation circuit of device.