Abstract: A brightness adjusting device has: a warm-up time determining unit which calculates a temperature difference between the outside temperature detected by an outside temperature detecting unit and the inside temperature detected by an inside temperature detecting unit and reading and determining a warm-up time corresponding to the calculated temperature difference, as an estimated warm-up time, from a product inside temperature table stored in a product inside temperature table storing unit; a target brightness value determining unit which reads and determines a target brightness value, which corresponds to the estimated warm-up time read and determined by a warm-up time estimating unit, from a target brightness value table stored in a target brightness value table storing unit; and a brightness value setting unit which sets a brightness value of the display device according to the target brightness value read and determined by the target brightness value calculating unit.

Abstract: A display device and a driving method thereof are disclosed. The display device includes a plurality of pixels arranged in a matrix with each pixel including first and second subpixels. First gate lines are connected to the first subpixel and transmit a first gate-on voltage, second gate lines are connected to the second subpixel and transmit a second gate-on voltage, and data lines are connected to the first and second subpixels and transmit first and second data voltages. The respective first and second data voltages that are applied to the first and second subpixels are obtained from the same image information, the first data voltage is not higher than the second data voltage, and the second data voltage is precharged in the data lines before applying the first data voltage to the first subpixel.

Abstract: A liquid crystal display device includes: first and second substrates between which a liquid crystal forming material is sandwiched and which are disposed to be opposite to each other; a pair of electrodes including one and the other electrodes; a control means for controlling a voltage applied between the electrodes; and a temperature detector. The control means applies a voltage, by which a change of light transmittance occurs based on an induction and disappearance phenomenon of a nematic phase in the liquid crystal forming material, between the electrodes when a temperature of the liquid crystal forming material is in an isotropic phase temperature range, and the control means applies a voltage, by which a change of light transmittance occurs based on a change of orientation of directors of the liquid crystal forming material, between the electrodes when the temperature of the liquid crystal forming material is in a nematic phase temperature range.

Abstract: A backlight is provided that can prevent light emitting elements and other circuit components from undergoing degradation due to temperature elevation during backlight operation. A display device utilizing the backlight is also provided.

Abstract: A displaying apparatus includes a signal input unit through which an analog image signal is input, an A/D converter to convert the analog image signal input through the signal input unit into a digital image signal according to a preset offset value thereof, a monitoring unit to sense a generation of an abnormal operating condition of the A/D converter, and a controlling unit to store information on a desired reference digital image signal corresponding to the preset offset value, to compare the digital image signal output from the A/D converter with the desired reference digital image signal information when the generation of an abnormal operating condition of the A/D converter is sensed by the monitoring unit, and to the preset offset value of the A/D converter when the digital image signal output from the A/D converter is different from the desired reference digital image signal, so that the digital image signal output from the A/D converter matches the desired reference digital image signal.

Abstract: A liquid crystal display device includes: a liquid crystal panel; a temperature sensing means configured to measure a real-time temperature of the liquid crystal panel; a backlight unit configured to supply a light to the liquid crystal panel; a control unit configured to convert an image signal into an RGB signal and to convert a first dimming signal to a second dimming signal according to the real-time temperature; and an inverter unit configured to adjust the backlight unit using the second dimming signal.

Abstract: Embodiments of the present invention provide a method for driving a liquid crystal display (LCD) device using gray-scale voltages whose dynamic ranges are different from each other depending on pixel color. The gray-scale voltages are output to a source line driver. Embodiments of the invention also provide a gray-scale voltage generation circuit coupled to a LCD source line driver. The disclosed method and circuit reduce coupling phenomena in source lines to substantially remove artifacts such as stripes or flicker in an LCD device.

Abstract: A liquid crystal display of the present invention facilitates grayscale level transition from a previous frame to a current frame, in such a manner that a modulation driving process section reads out, from one look-up table, corrected image data corresponding to a combination of image data of a previous frame and image data of a current frame and then outputs this corrected image data, irrespective of the ambient temperature. Meanwhile, a temperature circuit controls a heater so as to either stop the heating by the heater when a temperature of the liquid crystal panel exceeds a threshold value which is 1° C. through 1.5° C. higher than a target temperature, or start the heating by the heater when the temperature of the liquid crystal panel goes below a threshold value which is 1° C. through 1.5° C. lower than the target temperature, the target temperature being determined in advance to be in a range between 48° C. and 63° C.

Abstract: A DC-DC converter includes a temperature compensation circuit arranged between a feedback differential amplification circuit and an output voltage detection circuit to compensate the variation of the voltage level of the DC output voltage of the converter caused by ambient temperature changes. The temperature compensation circuit includes a temperature detection circuit that detects the ambient temperature and, in response thereto, generates a temperature signal; and a current source circuit that is connected between a feedback signal input terminal of the feedback differential amplification circuit and the output voltage detection circuit. The current source circuit, based on the temperature signal, generates an electrical current and a compensation voltage proportional to the electrical current. The compensation voltage is applied to the DC output voltage to thereby regulate the voltage level of the DC output voltage.

Abstract: A driving device for driving a light emitting unit includes a power supply for generating power according to a control signal, an active signal generator for generating an active signal sequence according to lighting features of the light emitting unit, a heat-dissipation signal generator for generating a heat-dissipation signal sequence, a multiplexer coupled to the active signal generator and the heat-dissipation signal generator for combining the active signal sequence and the heat-dissipation signal sequence, so as to generate a driving signal sequence, a burst signal generator for generating a burst signal according to the lighting features of the light emitting unit, and a logic unit coupled to the multiplexer, the burst signal generator and the power supply for timely outputting the driving signal sequence according to the burst signal, so as to generate the control signal.

Abstract: An image display device for displaying an image on a display panel is provided. The image display device includes a temperature variation rate detecting unit that detects a temperature variation rate of the display panel; a driving condition setting unit that sets driving conditions so as to display the image on the display panel in accordance with an image data of the image; a driving condition changing unit that changes the set driving conditions in accordance with the detected temperature variation rate; and a display panel driving unit that displays the image on the display panel by driving the display panel with the driving conditions changed by the driving condition changing unit.

Abstract: A liquid crystal display that is capable of maintaining a consistent display quality regardless of variations in the liquid crystal panel temperature is presented. The liquid crystal display includes a liquid crystal panel that displays an image and a driving circuit that drives the liquid crystal display panel. The liquid crystal display panel has a temperature sensor that senses temperature variation in the liquid crystal panel and outputs a sensing signal. The driving circuit adjusts a gamma value in response to the sensing signal and drives the liquid crystal panel based on the adjusted gamma value. The gamma value is adjusted by measuring a shift in the gamma value and applying a compensation factor that is opposite in polarity but similar in magnitude to the shift.

Abstract: A temperature-compensating circuit for a liquid crystal display device includes a temperature-sensing unit that measures the temperature of the liquid crystal display device and the surrounding ambient temperature. The temperature-sensing unit outputs a gate voltage-converting signal using the measured temperature. A DC/DC converting unit generates a plurality of converted gate signals using the gate voltage-converting signal. Absolute values of the plurality of converted gate signals are different from each other.

Abstract: A circuit for overdriving an LCD panel according to an image data and a temperature, and the corresponding are disclosed. The circuit includes: a memory for storing a previous image data; a plurality of LUTs, each coupled to receive the previous image data from the memory and a present image data, for storing overdrive values; a first temperature sensor, for sensing the temperature of a first area of the LCD panel to generate a first temperature data; a control circuit, for generating a selection signal and a temperature correction coefficient according to the first temperature data; a selection circuit, coupled to the plurality of LUTs, for selecting one LUT from the plurality of LUTs according to the selection signal and outputting the overdrive value of the selected LUT; and an overdrive processor, for generating adjusted image data according to the overdrive value and the temperature correction coefficient.

Abstract: An image display apparatus that displays an image on a display includes: a temperature measuring unit that measures temperatures of a plurality of display regions of the display; a determining unit that determines whether or not a temperature difference between one of the plurality of display regions and the other display regions is larger than a threshold value on the basis of the temperatures measured by the temperature measuring unit; a driving condition setting unit that sets a driving condition for displaying the image on the display according to image data of the image; a driving condition changing unit that, in a case when the determining unit determines that the temperature difference is larger than the threshold value, changes the set driving condition to a driving condition different from that in a case in which the temperature difference is determined to be equal to or smaller than the threshold value; and a display driving unit that drives the display under the driving condition changed by the dri

Abstract: A display device comprising an array of pixels, with gates of thin film transistors of the pixels in a row connected to a row conductor. Row driver circuitry provides row address signals for controlling the switching of the transistors of the pixels of the row including an ON gate voltage and an OFF gate voltage. Control circuitry shifts the ON gate voltage and the OFF gate voltage in dependence on drive and/or environmental conditions such as temperature and/or refresh rate. The control circuitry maintains a constant difference between the ON gate voltage and the OFF gate voltage. This allows the gap between the on and off voltages to be reduced, which results in power savings. The kickback voltage is kept constant so that kickback compensation is kept simple.

Abstract: A system for powering and controlling an LED backlight, the system comprising: a control circuitry; a plurality of LED strings; a pulse width modulation functionality associated with the control circuitry and arranged to pulse width modulate a current flow through each of the plurality of LED strings; and a plurality of current limiters responsive to the control circuitry, each of the plurality of current limiters being associated with a particular one of the plurality of LED strings and operative to limit current flow of the pulse width modulated current there-through, the control circuitry being operative in the event of a thermal condition of one of the plurality of current limiters to reduce a duty cycle of the pulse width modulation functionality of the current flow through the one of the plurality of current limiters.

Abstract: A method of operating a display includes deriving first pixel data for overdriving pixel circuits of the display from initial gray levels to target gray levels based on values in the first and second lookup tables, rendering the second lookup table unavailable in memory in response to a change in a temperature of the display, and deriving second pixel data using the first lookup table for overdriving the pixel circuits when the second lookup table is unavailable in the memory.

Abstract: A liquid crystal device including a pair of substrates that are provided opposite to each other with a liquid crystal layer being disposed therebetween, a pair of electrodes provided for each intersection of a plurality of scanning lines and a plurality of data lines, the pair of electrodes driving the liquid crystal layer, a driving circuit that applies a driving voltage to the pair of electrodes, an electric current detection element that detects a value corresponding to an electric current that flows in the liquid crystal layer when the driving voltage is applied, and a temperature information output circuit that outputs temperature information of the liquid crystal layer based on the value corresponding to the electric current.

Abstract: One embodiment of the present invention discloses: a backlight lamp lighting control device including: a PWM signal generating section for generating a PWM signal in accordance with a duty ratio externally inputted, and outputting the PWM signal to a PWM inverter section controlled by the PWM signal so as to drive a fluorescent lamp to light; and a tube current detecting section for detecting a current flowing in the fluorescent lamp, the PWM signal generating section generating the PWM signal based on a current, which is obtained by adjusting the current detected by the tube current detecting section in accordance with the duty ratio externally inputted, so that luminance displayed on a liquid crystal display panel will be substantially uniform over the entire liquid crystal display panel. With the arrangement, a difference between luminance on a high voltage side and luminance on a low voltage side in a lamp of a backlight can be reduced.

Abstract: The present invention relates to a driving apparatus for a display device and a display device including the same, as well as a method of driving a display device. The driving apparatus for a display device including a plurality of pixels each with a switching element has a driving voltage generator for generating a first driving voltage at a temperature higher than a reference temperature relative to a predetermined ambient temperature and a second driving voltage higher than the first driving voltage at a temperature lower than the reference temperature, and a gate signal generator for generating a plurality of gate voltages based on the driving voltage. In this manner, power consumption can be reduced by increasing a driving voltage only at a temperature that requires low temperature driving.

Abstract: An apparatus and method for driving a small-sized or low-powered liquid crystal display (LCD) device are provided to reduce the amount of energy consumed in driving the LCD device while displaying a high-quality moving image on a small-sized LCD panel without distortion such as tailing or blurriness, where the apparatus includes a compensation unit, a storage unit, an output unit, and a control unit.

Abstract: A method of driving a liquid crystal display in which frames having data values indicate the gray scale for liquid crystal in a display panel including the steps of determining a modulating data value for a first temperature interval within a temperature range, storing the modulating data as look-up table, sensing a temperature of a display panel, and modulating the input signal to the liquid crystal display based upon the sensed temperature.

Abstract: A gray scale bistable electro-optic display is driven by storing a look-up table containing data representing the impulses necessary for transitions, storing data representing at least an initial state of each pixel of the display, storing data representing temporal and gray level prior states of each pixel, receiving an input signal representing a desired final state of at least one pixel of the display; and generating an output signal representing the impulse necessary for a transition, as determined from the look-up table, dependent upon the temporal and gray level prior states. Other similar methods for driving such displays are also disclosed.

Abstract: A method and apparatus for gamma correction and a flat panel display using the same. Weighted values corresponding to red, green and blue of an image signal are respectively evaluated to determine the dominant color in the image signal, and a Gamma correction based on the dominant color is then performed, thereby obtaining displaying quality similar with that obtained by independently performing red, green, or blue Gamma correction.

Abstract: A lighting control system suitable for a surgical lighting device. The lighting control system includes circuitry that compensates for the effects of temperature changes in a lighting device, and that compensates for forward voltage variations among LED lighting modules to provide substantially uniform light output.

Abstract: Provided is a method and an apparatus for driving a display panel with a temperature compensated driving voltage, which comprises a temperature sensor, a temperature section register, a comparing unit, a voltage register, a voltage controller and a driver. The comparing unit compares temperature data output from the temperature sensor to temperature section data stored in the temperature section register and outputs comparison data having predetermined bits. The voltage controller selects voltage data corresponding to the comparison data from the voltage data stored in the voltage register and outputs a voltage control signal corresponding to the selected voltage data. The driver outputs a driving voltage corresponding to the voltage control signal to the display panel from among the different driving voltages.

Abstract: Numerous embodiments of a carrier substrate having thermochromatic materials are described. In one embodiment of the present invention, a carrier substrate has a visible surface, and a thermochromatic material is disposed near the carrier substrate. The thermochromatic material produces a visual change of the visible surface when an activation temperature of the thermochromatic material is reached.

Abstract: A liquid crystal display apparatus includes a liquid crystal panel having a matrix of pixels, a control circuit, and a temperature sensor. The temperature sensor directly or indirectly detects a temperature of the liquid crystal panel. The control circuit reverses a polarity of a voltage applied to each pixel at a time interval variable with the detected temperature, while keeping a field frequency constant. The time interval is a positive integer multiple of the reciprocal of a field frequency, i.e., a positive integer multiple of a field period. When the temperature of the liquid crystal layer is low, the control circuit reverses the polarity of the voltage at a longer time interval. In contrast, when the temperature of the liquid crystal layer is high, the control circuit reverses the polarity of the voltage at a shorter time interval.

Abstract: A liquid crystal display (LCD) device comprises a liquid crystal panel assembly having pixels and thin film transistors, a sensor sensing temperature, a image signal modifying portion receiving image signals and the temperature, calculating a plurality of reference data for modification with respect to the temperature using coefficient of quadratic equation, and generating modified images signals according to the reference data for modification for the image signals for previous and current frame; and a data driving portion converting the modified image signals into data voltages and supplying the data voltages to the liquid crystal panel assembly. According to this configuration, the liquid crystal display device may reduce the size of the memory by calculating modified image signals with respect to the temperature using PQI.

Abstract: The present invention provides an information processing apparatus having: a display controlling unit for starting any one of a plurality of application programs and displaying contents on a display screen; a determining unit for determining the application program started by the display controlling unit; and a changing unit for changing a plurality of image quality parameters for setting image quality of the display screen in accordance with the application program determined by the determining unit.

Abstract: An electro-optical device includes a pixel that has an electro-optical element with a light transmittance that changes to a predetermined value in response to an applied voltage, which changes in response to the temperature. A light source irradiates light to the pixel. A driving unit includes a predetermined number of sub-fields having the same length in one frame. The driving unit provides either an on-voltage indicating light-on or an off-voltage indicating light-off to the pixel in each of the predetermined number of the sub-fields in response to the grayscale to be displayed. A temperature measuring unit measures the temperature and outputs a temperature signal. A time controlling unit controls the length of one sub-field on the basis of the temperature signal. A light intensity controlling unit controls the intensity of the light incident on the pixel on the basis of the temperature signal.

Abstract: The present invention provides a method and apparatus for controlling the thermal gradient and therefore the thermal stress in light-emitting elements in which the light-emitting elements are exposed to temperature gradients caused by varying drive current under operating conditions. The method and apparatus according to the present invention can reduce the thermal stress in a light-emitting element by adaptively determining a drive current transient for a required change in the drive current from a first drive current state to a desired second drive current state, wherein the drive current transient is adaptively determined in order to substantially minimize the change in applied voltage over time, during the transition time period.

Abstract: A light emitting display including a pixel area having a plurality of pixels, a scan driver for outputting a scan signal for selecting a predetermined pixel among the plurality of pixels of the pixel area, and an emission control signal for allowing a current to flow in the selected pixels. The scan driver includes: a signal generator adapted to generate the scan signal and the emission control signal; a first buffer adapted to transmit the scan signal to the pixel area; and a second buffer adapted to transmit the emission control signal to the pixel area. In the scan driver, the second buffer is smaller than the first buffer. The size of the second buffer is decreased to decrease the size of the scan driver, and/or to decrease the size of the predetermined pixel to get a high definition.

Abstract: A heating system for a display panel is provided herein, wherein the display panel has a display area. The heating system includes a sensor, a temperature controlling device, and a heating element. The sensor is used for sensing the temperature of the display panel. The temperature controlling device provides a control signal according to the temperature of the display panel. The heating element heats the display panel according to the control signal, and the heating element is a patterned circuitry disposed on a peripheral region of the display area.

Abstract: The present invention provides an image processing circuit capable of sufficiently correcting a temperature characteristic of a response speed, varying depending on gray-scale, of a liquid crystal display, while suppressing an increase in circuit scale.

Abstract: A liquid crystal display comprises a back light emitting monochromatic light, a liquid crystal display element comprising, a pair of opposing substrates, a nematic liquid crystal layer placed between the pair of opposing substrates, an electrode pattern formed on a nematic liquid crystal layer side of each substrate, a pair of polarizers placed outside the pair of substrates, and a controller which controls light emission of the back light and a voltage applied to the liquid crystal display element, wherein the controller restrain change in retardation of the liquid crystal display element by lowering non-selection voltage applied to the liquid crystal display element when environmental temperature increases and increasing non-selection voltage applied to the liquid crystal display element when environmental temperature decreases.

Abstract: A flat panel display, an image correction circuit and method thereof are provided. The image correction circuit mainly includes a digital to analog conversion unit and a data processing unit. The digital to analog conversion unit includes a temperature sensor and a gamma voltage generator. The gamma voltage generator is adopted for generating a plurality of gamma voltages, and the temperature sensor is electrically connected to the gamma voltage generator and adopted for sensing the working temperature of the gamma voltage generator. The data processing unit is electrically connected to the digital to analog conversion unit. When the working temperature of the gamma voltage generator changes to higher (or lower) than the room temperature, the data processing unit selects and outputs applicable digital data to the digital to analog conversion unit. Therefore, the digital to analog conversion unit outputs a predetermined gamma voltage at room temperature according to the digital data.

Abstract: A moving image portion that indicates a moving object moving not less than a given movement amount and a still image portion other than the moving image portion are distinguished with respect to a video signal. Video display data for displaying the moving image portion is generated by repeatedly using the same video signal by repetition times based on temperature of a liquid crystal panel. Movement display data for displaying movement positions of the moving image portion is then generated based on a video signal obtained after the video signal used for displaying the moving image portion and is combined with the video display data. This achieves an effect similar to that obtained by decreasing a field frequency and decreases a “tail trail” phenomenon of the moving object. Furthermore, the movement display data enables recognition of the almost actual position of the moving object.

Abstract: A liquid crystal display apparatus comprises a liquid crystal display panel, a temperature sensor which detects temperature of the liquid crystal display panel, and a controller which controls a voltage applied to the liquid crystal display panel. The controller sets a black-insertion ratio to 0% and changes the voltage applied in white-display mode to a voltage equal to or higher than the critical voltage, or sets a black-insertion ratio to a finite value and changes the voltage applied in the white-display mode to a voltage lower than the critical voltage, in accordance with the temperature detected by the temperature sensor.

Abstract: A liquid crystal driving device is provided, which can reduce the problem of contrast lowering of the liquid crystal display screen due to the decrease of the driving current of LED, by the control which is performed in order to cope with the decrease of the maximum rated current of LED as a light source of the backlight at a high temperature. The liquid crystal driving device includes a liquid crystal driving circuit, a backlight control unit, and display data expansion circuits. The liquid crystal driving circuit generates a liquid crystal driving signal to be supplied to a liquid crystal display panel in response to display data. The backlight control unit reduces driving current of the light emitting diode as a light source of the backlight module to illuminate the liquid crystal display panel, in response to the temperature rise of the liquid crystal display panel.

Abstract: An ambient light detection device for use with a liquid crystal display having an array of liquid crystal cells, each liquid cell having at least one transistor for selectively connecting that liquid crystal cell to a signal line and each transistor having a gate connected to a gate line and having a gate supply line selectively connectable to the gate line for turning off the gates. The device includes a current measuring circuit configured to measure the current flowing in the gate supply line as a result of gate leakage current in the gates to which the gate supply line is connected and a controller connected to the measuring circuit and configured to calculate, from the measured current, the level of ambient light reaching the gates.

Abstract: An overdriving apparatus and an overdriving method for a liquid crystal display (LCD) panel are disclosed. The overdriving apparatus includes a temperature measuring apparatus and an overdriving signal generator apparatus. The temperature measuring apparatus is coupled to the overdriving signal generator apparatus. The temperature measuring apparatus measures an operation temperature of the LCD panel. The overdriving signal generator apparatus generates a first overdriving signal according to a first image data of a current frame, x second image data of previous x frame(s), and the operation temperature, where x is a natural number.

Abstract: A cooling apparatus of a plasma display panel and a method for stabilizing the PDP to minimize the residual image on the display are disclosed. In particular, the present invention minimizes the residual image that is generated due to the degeneration of phosphors caused by a high voltage and a high temperature.

Abstract: An emphasis converter 52 compares the image data of the current vertical period with the image data of the previous vertical period and controls the input image data to a liquid crystal display panel 4 based on the emphasis conversion parameters stored in tables of ROMs 3a to 3c so as to achieve accelerated drive. A microcomputer 38 is able to realize stable control of selecting emphasis conversion parameters by adding hysteresis to the detected temperature from a thermistor 37 even when the detected temperature fluctuates up and down crossing the temperature threshold.

Abstract: A display device includes a panel assembly, a backlight unit supplying light to the panel assembly, a first photosensor, a second photosensor, a sensing signal processor and a signal controller. The first photosensor is supplied with ambient light and light from the backlight unit to generate a first sensing signal. The second photosensor is blocked from the ambient light and receives the light from the backlight unit to generate a second sensing signal. The sensing signal processor receives the first and the second sensing signals from the first and the second photosensors for processing. The signal controller determines a sensing state responsive to processed first and second sensing signals from the sensing signal processor and performing a predetermined control operation responsive to the sensing state.

Abstract: The invention relates to a display element, a display system having the element, and an image processing method. There is provided a display element having high display quality, a display system having the element, and an image processing method utilizing the element. The display element includes a display section having a first display layer exhibiting a first spectrum and a second display layer formed on the first display layer and exhibiting a second spectrum shifted from the first spectrum toward longer wavelength, a temperature sensor for detecting a temperature in the vicinity of the display section, and a control section for generating display image data to be displayed by the first and second display layers based on input image data and the temperature such that the tint of a displayed color associated with the input image data is kept substantially constant without depending on the temperature.

Abstract: A flat panel display device includes an electron emission substrate; an image forming substrate spaced apart from the electron emission substrate; a spacer disposed between the electron emission substrate and the image forming substrate; a detector coupled to the electron emission substrate for detecting a temperature value of the flat panel display device; a temperature controlling part for receiving the receiving the temperature value and for controlling a temperature of the electron emission substrate based on the received temperature value; and a cooler for cooling the flat panel display device to be at the temperature controlled by the temperature controlling part.

Abstract: A temperature sensing apparatus for a liquid crystal display device is disclosed. The apparatus can measure the device temperature without the existence of a conventional PN junction. The temperature sensing apparatus comprises at least one thin-film transistor (TFT) cell, a variable current source, a buffer and a sensing circuit. Each TFT cell has its respective drain and gate coupled together and a source coupled to a ground The variable current source is coupled to the drain of the TFT cell. The buffer has an input coupled to the drain of the TFT cell. The sensing circuit has an input coupled to an output of the buffer and an output to produce a voltage output signal. The temperature of the TFT cell is determined by inputting two currents at a sub-saturation region of the TFT cell and measuring voltage output signal difference.

Abstract: A color curve control circuit includes: a data input unit, for entering values for changing colors on the screen of a monitor; a microcomputer, for processing color signals corresponding to color temperature using stored color temperature data and a color curve control program, in order to change the colors on the screen according to signals generated by the data input unit, and for generating color gain signals and color cutoff signals; and a digital to analog converter for converting the digital color gain and cutoff signals from the microcomputer into analog signals.