KR20150005815A - Method and system for measuring color of display device - Google Patents

Abstract

A method and system for color measurement of a display device are disclosed. (a) displaying colors corresponding to the three primary colors on a display device; (b) sensing colors by a PD (Photo Diode) sensor provided with filters corresponding to the three primary colors to obtain X, Y, Z (C) measuring the color with a spectroscopic colorimeter, and (d) converting the value calculated in step (b) to a value corresponding to the value measured in step (c) And providing a deviation between the values measured in step (c), wherein the color measuring method of the display device is a means for performing color correction according to the user's intention, have.

Description

[0001] The present invention relates to a method and a system for measuring color of a display device,

The present invention relates to a color measuring method and system for a display device.

Colorimetry based on human senses is one of the most important measurements in light source and display quality assessment, in addition to photometry, and is closely related to people's lives.

For example, various statutory standards and regulations to ensure the safety of land and maritime traffic are based on color measurement values for various types of luminaires and reflectors used in signaling systems, and standardization methods The standard is also used as a very important indicator of color measurement.

In addition, as a lighting device using a new light source device such as a LED (Light Emitting Diode) has recently been introduced to the market, related industries and consumers are interested in evaluation of color characteristics of LED lighting.

The light source color measuring devices currently available in the field can be divided into two types, that is, filter type color spectrometer and spectroscopic radiometer, depending on the manner of implementing the tristimulus measurement of color. In addition, according to the geometrical conditions of the measurement, .

The filter type colorimeter generally implements a color matching function using three or four types of color filters and photodiodes. The device is easy to use and stable, while the performance of the color filter is measured There is a disadvantage that the error varies depending on the spectral distribution of the light source.

In the case of the spectroscope, the spectroscopic device is mounted therein, so that the spectral distribution and the wavelength characteristics can be measured independently of the type of the light source, and various color characteristics such as color temperature and color rendering index as well as color coordinates can be evaluated at the same time There are advantages.

As a result, universal laboratories and monitor manufacturers use spectrophotometric colorimeters (eg, Minolta CA-2000) as standard equipment.

We are operating color measuring equipment related to lighting and display in various places such as industrial sites, universities, research institutes, national calibration / testing institutes, and the demand for measurement is increasing increasingly.

FIGS. 1 to 3 are diagrams illustrating a color measurement mechanism according to a color measurement tool. FIG. 1 shows a color measurement mechanism through a human eye.

FIG. 2 is a schematic diagram showing a color measuring mechanism using a tristimulus colorimeter. The current signal of three filtered PD (tri-stimulus colorimeter) operating as a human eye is used as a color coordinate (XYZ) is measured.

FIG. 3 is a schematic view showing a color measuring mechanism through a spectroscopic spectroscope, in which a spectrum of an incident light is measured by a spectroscope and XYZ is calculated by numerical integration in the data.

The above-described background technology is technical information that the inventor holds for the derivation of the present invention or acquired in the process of deriving the present invention, and can not necessarily be a known technology disclosed to the general public prior to the filing of the present invention.

Korean Patent Laid-Open Publication No. 1999-013781 discloses a device for measuring the characteristics of a color display device. Korean Patent Laid-Open Publication No. 2001-0050607 discloses a technique for measuring the color of a reproduction medium and converting measurement values into color coordinates. Korean Patent No. 10-0730354 discloses a technique for measuring a transformer function for color correction of a display.

Patent Document 1: Korean Patent Publication No. 1999-013781 Patent Document 2: Korean Patent Publication No. 2001-0050607 Patent Document 3: Korean Patent No. 10-0730354

The present invention provides a method and system for measuring color of a display device capable of performing color measurement of an accurate display device as means for performing color correction in accordance with a user's intention.

Other objects of the present invention will become readily apparent from the following description.

According to an aspect of the present invention, there is provided a method of displaying a color image, comprising the steps of: (a) displaying a color corresponding to three primary colors on a display device; (b) sensing a color by a PD (Photo Diode) (C) measuring a color with a spectroscopic colorimetric system; and (d) comparing the value calculated in step (b) with the value measured in step (c) And then providing a deviation between the converted value and the value measured in step (c).

The step (a) may include transmitting color patch information so that red, green and blue are displayed on the display device.

Step (c) may include deriving a measured value by referring to a preset look-up table based on the data measured by the spectroscopic colorimeter.

The X, Y, and Z values of step (b) can be calculated according to the functional relationship expressed by equation (11).

(11)

here,

Is the measurement value derived in step (c)

Is a value obtained by sensing the color displayed on the display device by the PD sensor.

The conversion of step (d) may be performed according to the functional relationship expressed by equation (12).

(12)

here,

Is a measurement value by a spectroscopic colorimeter,

Is a measurement value by the PD sensor,

Is a transformation matrix calculated according to a function relationship represented by equation (14)

(14)

Is a measurement value of a spectroscopic colorimetric system for three colors,

Is the measurement value of the PD sensor for three colors.

According to another aspect of the present invention, there is provided a display device including a display device for displaying a color corresponding to three primary colors, a PD sensor for sensing a color displayed on the display device and having a filter corresponding to three primary colors, Y, and Z values in the CIE color space from the values sensed by the PD sensor, converts the calculated values to correspond to the measured values by the spectral side colorimeter, converts the converted values And a calculation unit for calculating a deviation between the measured value by the spectroscopic colorimeter and the measured value by the spectroscopic colorimeter.

And a control unit for transmitting color patch information so that red, green, and blue colors are displayed on the display device.

The measurement value by the spectroscopic colorimetric system can be derived by referring to a preset look-up table based on the data measured by the spectroscopic colorimetric system.

The X, Y, and Z values can be calculated according to the functional relationship represented by the equation (11).

(11)

here,

Is a measurement value by a spectroscopic colorimeter,

Is a value obtained by sensing the color displayed on the display device by the PD sensor.

The transformation can be made according to a function relationship represented by equation (12).

(12)

here,

Is a measurement value by a spectroscopic colorimeter,

Is a measurement value by the PD sensor,

Is a transformation matrix calculated according to a function relationship represented by equation (14)

(14)

Is a measurement value of a spectroscopic colorimetric system for three colors,

Is a measurement value of the PD sensor for three colors for three colors.

Other aspects, features, and advantages will become apparent from the following drawings, claims, and detailed description of the invention.

According to an embodiment of the present invention, color measurement of an accurate image display device can be performed as means for performing color correction according to a user's intention.

1 is a schematic diagram showing a color measurement mechanism through a human eye;
FIG. 2 is a schematic view showing a color measurement mechanism through a tristimulus colorimeter. FIG.
3 is a schematic diagram showing a color measurement mechanism through a spectroscopic spectroscope.
4 is a graph showing the color matching function of the CIE standard observer.
5 is a graph showing a CIE xy chromaticity distribution table of the CIE 1931 color space.
6 is a graph showing the color gamut of CIE RGB and its position in the CIE 1931 xy chromaticity coordinate system.
7 is a graph showing the CIE 1931 RGB color matching function.
8 is a block diagram illustrating a color measurement process of a display device according to an embodiment of the present invention.
9 is a diagram illustrating a configuration of a color measurement system of a display device according to an embodiment of the present invention.
10 is a flowchart showing a color measuring method of a display device according to an embodiment of the present invention.
11 is a graph showing a result of performance evaluation of a color measurement system according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Referring to the accompanying drawings, the same or corresponding components are denoted by the same reference numerals, .

FIG. 8 is a block diagram illustrating a color measurement process of a display device according to an embodiment of the present invention, FIG. 9 is a diagram illustrating a structure of a color measurement system of a display device according to an embodiment of the present invention, FIG. 11 is a graph illustrating a result of performance evaluation of a color measuring system according to an exemplary embodiment of the present invention. Referring to FIG. 8 to 11, a display device 10, a controller 12, a PD sensor 100, a spectroscopic colorimeter 110, and a calculator 120 are shown.

The present embodiment relates to a color measuring method and system including an image processing apparatus and a display apparatus.

The image display color measurement system according to the present embodiment includes a controller 12 for transmitting color patch information for color measurement to the display device 10, an RGB color displayed on the display device 10 by the transmitted color patch information And a memory unit for storing a look up table (LUT) to be referred to in the XYZ transformation calculation in order to accurately express the color information displayed on the image display apparatus 10. [

Through the optic nerve, the human eye senses and identifies the color, and as it grows, it becomes increasingly discriminating by judging and judging various kinds of colors through life and education.

Typically, people recognize dozens of distinct colors separated from each other, and about 1,000 painters and color-related designers with distinctive colors. On the other hand, when two similar colors are compared side by side, it is known that the ability of both sides to identify the same index and different index can distinguish about 7.5 million colors.

In general, if you have 50 colors that are easy to distinguish, you can name your own colors using the name or compound of the objects they represent, but if it's about 7.5 million colors, it's almost impossible to name them . Accordingly, a variety of coloring methods have been devised which can name colors as numerical values.

Basically, a person recognizes a color using the value of the stimulus given to the three cells of the eye, so that the above-mentioned value of the stimulus can be used as a basic value for expressing the color. That is, any color can be represented by a combination of three values (that is, in the form of a three-dimensional coordinate), so that it can be expressed in the form of one point on three dimensions.

Since the spectral distribution of each wavelength optically represented by the physical approach takes an arbitrary function form, it can be said to be an infinite dimension, so that the human color recognition ability is much weaker than the prism or diffraction grating.

Since the person feels light according to the unique wavelength in the physical sense and recognizes that the color is different, information about the spectrum of light has all the information of that color.

However, since color depends on human senses through the optic nerve of the eye, it has been found that the human eye has three color cells with different sensitivities depending on the light wavelength or spectrum. It is now possible to express the degree to which these three cells feel, physically and mathematically, to differentiate.

The CIE 1931 XYZ color space (or CIE 1931 color space) is one of the first mathematically defined color spaces based on studies of human color perception and was enacted in 1931 by the International Lighting Commission (CIE). In the 1920s, based on the work of W. David Wright and John Guild, the CIE RGB color space was created, and based on that, the CIE XYZ color space was created again.

There are cone cells in the human eye, which are receptors that accept three kinds of light: short wavelength, medium wavelength, and long wavelength. Therefore, a combination of three colors sensitive to these three cells can express arbitrary colors. In fact, almost all of the colors are made of three colors of red (R), green (G), and blue This is called the primary color or tristimulus value.

The tricolor stimulus value refers to a combination that can produce the same color as the desired color by combining the three primary colors in the additive mixture model. The tricolor stimulus values can be expressed as X, Y, Z values in the CIE 1931 color space.

The color space refers to a mathematical model that associates each of these three stimulus values with their respective colors. Among the various color spaces, CIE XYZ is a special color space that is the basis for making various color spaces because it is made by directly measuring human color perception.

In the CIE XYZ color space, X, Y, and Z represent colors similar to red, green, and blue, respectively. Mixing two colors with different wavelengths may look similar to other colors, and this phenomenon is called conditional coloration.

In the CIE XYZ color space, the sum of the tricolor stimulus values of two colors is equal to the tricolor stimulus value of the other color that looks the same regardless of the wavelength of the two colors.

Because the cone of the eye is not uniformly distributed, the value of the trichromatic stimulus varies slightly depending on the observer's field of view. To eliminate this difference, the CIE defined a standard color observer.

The standard color observer refers to the reaction of the cone cell within a viewing angle of 2 ° of a person with an average vision. Thus, the CIE 1931 standard observer is also referred to as the CIE 1931 2 ° standard observer. The standard observer can be represented by a three-color corresponding function.

The color matching function is a numerical description of the observer's color reaction. CIE defines three color matching functions x (λ), y (λ), and z (λ). This can be said to be a response function of the cone cell to each of the three color stimulus values X, Y and Z, respectively. These three functions are collectively called a CIE standard observer, and the tricolor stimulation value of light having a wavelength? Can be determined from FIG. 4 and equation (1).

FIG. 4 is a graph showing a color matching function of a CIE standard observer, wherein (.lambda.) Is the wavelength of light and the unit is nanometer. In (1), I (λ) denotes the spectral power distribution function.

(One)

Since the human eye has three color receptors, the distribution of all visible light can be represented in the form of a three-dimensional graphic.

On the other hand, color can be divided into two factors, brightness and chromaticity. For example, white can be a light color and gray can be represented in a darker form with the same white. In other words, white and gray have the same color but different brightness.

The CIE XYZ color space is designed such that the Y value is a value of brightness or illuminance. Therefore, the chromaticity of a color can be expressed as two values x, y calculated from X, Y, and Z as shown in equation (2).

(2)

5 is a graph showing a CIE xy chromaticity distribution table of the CIE 1931 color space. The curved boundary line of the outline corresponds to monochromatic light, and the wavelength of each monochromatic light is indicated by the nanometer.

The color space represented by x, y, and Y is called CIExyY color space, and is often used for displaying colors. 6 is a graph showing the positions of the three primary colors gamut of CIE RGB and CIE 1931 xy chromaticity coordinate system.

The CIE RGB color space is one of the RGB color spaces, and monochromatic color is used as the three primary colors.

In the 1920s, W. David Wright and John Guild conducted experiments on human vision, respectively. This was later the basis for the enactment of CIE XYZ.

The experiment consisted of two circular screens of the same size with a viewing angle of 2 ° corresponding to the center of the human eye. On one side of the screen, the test color was reflected, while on the other side, the three primary colors that the observer could manipulate were blended.

The observer was unable to adjust the chromaticity of this color but could adjust the brightness of the color. The observer manipulated the three lights until the test color and size were the same. All colors could not be the same color as the test color. In this case, one of the three primary colors was added to the test color and the other two colors were manipulated to create the same color. At this time, the primary color added to the test color was considered to have a negative value.

In this way, we were able to test all the colors that humans can see. For the test color with monochromatic light, the graph of the brightness of the three primary colors corresponding to each test color was called the color correspondence function.

Light and guilds are repeated monochromatic light with various wavelengths and brightness, and this result can be summarized as CIE RGB color matching function r (λ), g (λ), b (λ). The three functions were measured on the basis of the three primary colors of 700 nm (red), 546.1 nm (green), and 435.8 nm (blue) to be.

FIG. 7 shows a graph showing three CIE 1931 (RGB) color matching functions. The color matching function represents the amount of the three primary colors required to correspond to a color such as monochromatic light corresponding to the wavelength of the horizontal axis.

The wavelengths of 546.1 nm and 435.8 nm were chosen because they were easily obtainable from the spectral spectrum of mercury vapor. The wavelength of 700 nm was not the wavelength that could be easily produced at the time, but because the color of the eye did not vary greatly in this region, it was chosen because it would have a relatively small impact on the error.

Color matching functions and tricolor colors were selected as a standard by careful deliberation of the CIE special committee. "1931 CIE Standard Observer" is defined by such a color matching function. The maximum value of the x-axis on the graph is virtually fixed. Humans can recognize light up to 810 nm, but its sensitivity is only a few thousandths of a meter compared to green light.

In addition, the graph does not represent the absolute brightness of each of the three primary colors but is normalized so that the area under the graph has the same area. In other words, the color matching function is made to satisfy equation (3).

(3)

As a result, the standardized color matching function was made such that r: g: b had a luminance ratio of 1: 4.5907: 0.0601 and an emission rate of 72.0962: 1.3791: 1. Therefore, the RGB stimulus value of a color whose spectral power distribution is I (λ) is expressed by Equation (4)

(4)

FIG. 8 shows a color measurement process of the display device 10 according to the present embodiment. FIG. 9 shows a configuration of a color measurement system according to the present embodiment, in which the RGB of the monitor is XYZ The color measurement is performed in such a manner that the color measurement is performed.

The color measurement system of the display device according to the present embodiment may be configured to include the display device 10, the PD sensor 100, the spectral side colorimeter 110, and the calculation unit 120.

The display device 10 displays colors corresponding to the three primary colors, and can display red (R), green (G), and blue (B), for example. To this end, the display device 10 according to the present embodiment may be provided with a control unit 12 for transmitting color patch information on colors to be displayed.

The PD sensor 100 is a component for sensing the color displayed on the display device 10 and may be provided with a filter corresponding to the three primary colors so as to be used as a tristimulus colorimeter as described later.

The spectroscopic colorimeter 110 is a component for measuring the color displayed on the display device 10, and standard equipment such as, for example, Minolta CS-2000A can be used. The measured value by the spectrometric colorimeter 110 can be derived by referring to a preset lookup table based on the data measured by the spectrometric colorimeter 110.

The arithmetic unit 120 calculates X, Y, and Z values in the CIE color space from the values sensed by the PD sensor 100, and converts the calculated values to correspond to measured values by the spectral colorimetric system 110 , And calculates the deviation between the converted value and the measured value by the spectroscopic colorimeter 110.

The calculation of the X, Y, and Z values will be described with reference to Equation (11) to be described later, and the conversion of the calculated values will be described with reference to Equation (12).

The color measuring method and system according to this embodiment is characterized in that a tri-stimulus colorimeter is used in this embodiment in order to adjust the three colors (RGB) from the monitor to the reference level (Minolta CS-2000A) .

The color measurement system according to the present embodiment can make the color measurement values of the reference equipment and the color measurement values of a general tristimulus colorimeter coincide with each other within a certain level regardless of environmental changes such as input color, monitor change, temperature and humidity.

Data (RGB _meas ) measured by a _monitor (RGB _monitor ) with a three-stimulus colorimeter (filtered PD sensor) follows regular data (Grid Data), and information The data (XYZ _ref ) measured with the reference instrument (spectrometer CS-2000A) also conforms to the regular data.

However, at the same time, a normal data distribution is not formed between the data measured by the three-stimulus colorimeter and the data measured by the spectral-side colorimeter 110 in the RGB three colors emitted from the monitor in the same environment.

The relationship between these two data shows scattered data distribution. The relationship between the two is merely a measurement of the RGB output from the monitor, and the tristimulus colorimeter or the spectrophotometric colorimeter 110 does not know the RGB value of the monitor.

Since the tristimulus colorimeter simply informs us of the information generated about the intensity of the light when displaying a certain color in the monitor, the data distribution space represented by the tristimulus colorimeter and the spectral-side colorimetric 110, The data distribution space represented by the data distribution does not coincide with each other, and hence the relationship between the two can be referred to as a non-regular data distribution as shown in equation (5).

(5)

In the color measuring method according to the present embodiment, first, the three primary colors are displayed on the display device 10 (S100). The RGB color patch information can be transmitted to the display device 10 for displaying the three primary colors as described above.

Next, the colors indicated by the PD sensor 100 equipped with the three primary color filters are sensed to calculate X, Y, and Z values in the CIE color space (S200). The calculation of the X, Y, and Z values will be described in detail with reference to Equation (11) to be described later.

Meanwhile, the color displayed on the display device 10 is measured using the spectroscopic colorimeter 110 (S300). The measurement step of the spectrometric colorimetric system 110 and the sensing step of the PD sensor 100 are not related to each other, either of which may be performed first or simultaneously. The measurement value can be derived by referring to a preset LUT for color measurement by the spectral side colorimeter 110 as described above.

Next, the calculated X, Y and Z values are converted so as to correspond to the measured values by the spectroscopic colorimeter 110, and the deviation between the converted values and the measured values by the spectrometric colorimeter 110 is derived (S400 ). The conversion of the X, Y and Z values will be described in detail with reference to the following equation (12).

Hereinafter, a process of measuring and correcting three colors (RGB) of a monitor using the color measuring system according to the present embodiment will be described in detail.

The emission mechanism of the monitor is as follows. First, white light having a certain spectrum is irradiated through the back light unit (BLU) in the same manner as in the back of the RGB pixel. The intensity of light is adjusted by two polarizers perpendicular to each other at the position of each RGB pixel and a liquid crystal that returns polarized light according to the input signal. Each of the intensity-adjusted lights passes through R, G, and B color filters to realize intensity-adjusted ternary colors.

The light source conditions of the artificial color realized through the LCD monitor by the above-described light emission mechanism are as follows. The spectrum of the light is constituted by a linear combination of the three primary colors, and all the colors are represented by a pair of (R, G, B) . That is, the following equation (6) can be established.

(6)

As described above, a light source that expresses color as a linear combination of specific three primary colors is called an artificial color light source.

Next, the correction process between the input XYZ and the reference XYZ will be described.

Firstly, the XYZ coordinate value can be determined. When the intensity of the input light is I (λ) when the condition of the light source to be measured satisfies the condition that it is an artificial color light source (the monitor light satisfies the artificial color light source condition) Can be determined according to the following equation (7) with reference to FIG.

(7)

The summation of the phase integral is shown in Equation (8).

(8)

Substituting Eq. (8) into Eq. (7) and calculating X, we can obtain Eq. (9).

(9)

In equation (9), I _R (λ), I _G (λ), I _B (λ) and x (λ) are device dependent and do not depend on the color change. The equation (9) can be expressed simply as the following equation (10).

(10)

If we extend equation (10) not only to X but also to Y and Z, a linear transformation relation expressed by a matrix can be obtained as in equation (11). Each element of the matrix is device dependent and does not depend on color.

(11)

here,

Is the XYZ value for the monitor color calculated by applying the value measured by the tristimulus colorimeter to the conversion matrix,

Is the measured value of the standard instrument found in the LUT, is used as the transformation matrix (M) in the XYZ calculation,

Represents the value measured by the sensor for any color of the monitor.

The X, Y, Z matrix calculations in equation (11) can be solved as follows.

X = (X _R × R) + (X _G × G) + (X _B × B)

Y = (Y _R × R) + (Y _G × G) + (Y _B × B)

Z = (Z _R × R) + (Z _G × G) + (Z _B × B)

(XYZ) _R , (XYZ) _G , and (XYZ) _B are the values measured by the standard equipment found in the LUT.

Therefore, there is a linear conversion relationship expressed by a matrix between a measured value by a general tri-stimulus colorimeter (filtered PD sensor) and a reference instrument, and the element of the conversion matrix is a three-color spectrum of an artificial color light source, Responsibility of the colorimeter light receiver depends on the response of the reference instrument.

Next, the relationship between the input XYZ and the reference XYZ will be described.

For a single input color, the measured value by a general tristimulus colorimeter (filtered PD sensor) product and the measured value by a reference device can be defined as the following equation (12), respectively.

(12)

In equation (12), M _our , M _ref depends on the physical configuration of the light source and the light receiving part. At this time, there is a relationship as shown in the following equation (13) between the two measured values.

(13)

Next, the process of determining the above-described conversion matrix will be described. In order to determine the elements of the transformation matrix, each M value may be calculated separately, or it may be determined experimentally immediately.

(X1 _our , X1 _ref ), (X2 _our , X2 _ref ), and (X3 _our , X3 _ref ), respectively, when measured by the three-pole colorimeter , The following equation (14) is established.

(14)

Thus, the transformation matrix can be determined through measurements on three different colors. At this time, in order to define the inverse matrix and the matrix multiplication, X _our , X _ref must be a 3 × 3 matrix, and therefore, measurement of at least three RGB values is required.

The results of evaluating the performance of the color measuring system according to this embodiment as a result of measuring and correcting the three colors of the monitor according to the process described above are shown in FIG.

11A is a graph showing deviations of x values determined by the CIE standard and measured by the color measuring system (filtered PD sensor) and the standard equipment (spectrometer) according to the present embodiment, ) Is a graph showing the deviation of the y value determined by the CIE standard and measured by the color measuring system and the standard equipment according to the present embodiment, FIG. 11 (c) And the deviation of the determined Y value.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. It will be understood that the invention may be varied and varied without departing from the scope of the invention.

10: display device 12:
100: PD sensor 110: Spectral side colorimeter
120:

Claims (10)

(a) causing a display device to display a color corresponding to the three primary colors;
(b) sensing X, Y and Z values in the CIE color space by sensing the color with a PD (Photo Diode) sensor provided with a filter corresponding to the three primary colors;
(c) measuring the color with a spectroscopic colorimeter; And
(d) converting the value calculated in step (b) to a value corresponding to the value measured in step (c), and then providing a deviation between the converted value and the value measured in step (c) Of the display device.
The method according to claim 1,
Wherein the step (a) comprises transmitting color patch information such that red, green and blue are displayed on the display device.
3. The method of claim 2,
Wherein the step (c) includes a step of deriving a measured value by referring to a preset look-up table based on the data measured with the spectroscopic colorimeter Way.
The method of claim 3,
Wherein the X, Y, and Z values of the step (b) are calculated according to a function relationship expressed by the following equation (11).

(11)
here,
remind

Is the measurement value derived in the step (c), and

Is a value obtained by sensing the color displayed on the display device by the PD sensor.
5. The method of claim 4,
Wherein the conversion of the step (d) is performed according to a function relationship expressed by the following equation (12).

(12)
here,
remind

Is a measurement value by the spectroscopic colorimeter,

Is a measurement value by the PD sensor,

Is a transformation matrix calculated according to a function relationship expressed by the following equation (14)

(14)
remind

Is a measurement value of the spectroscopic colorimetric system for three colors,

Is a measurement value of the PD sensor for the three colors.
A display device for displaying a color corresponding to the three primary colors;
A PD sensor sensing a color displayed on the display device and having a filter corresponding to three primary colors;
A spectroscopic colorimeter for measuring a color displayed on the display device;
Calculating X, Y and Z values in the CIE color space from the values sensed by the PD sensor, converting the calculated values to correspond to measured values by the spectroscopic colorimeter, And a calculation unit for calculating a deviation between measured values by the measurement unit.
The method according to claim 6,
Further comprising a controller for transmitting color patch information such that red, green and blue colors are displayed on the display device.
8. The method of claim 7,
Wherein the measured value by the spectroscopic colorimetric system is derived by referring to a preset look-up table based on the data measured by the spectroscopic colorimetric system.
9. The method of claim 8,
Wherein the X, Y, and Z values are calculated according to a function relationship expressed by the following equation (11).

(11)
here,
remind

Is a measurement value by the spectroscopic colorimeter,

Is a value obtained by sensing the color displayed on the display device by the PD sensor.
10. The method of claim 9,
Wherein the conversion is performed according to a function relationship expressed by the following equation (12).

(12)
here,
remind

Is a measurement value by the spectroscopic colorimeter,

Is a measurement value by the PD sensor,

Is a transformation matrix calculated according to a function relationship expressed by the following equation (14)

(14)
remind

Is a measurement value of the spectroscopic colorimetric system for three colors,

Is a measurement value of the PD sensor for the three colors.

Images