JP2010237350A - Measurement method for measuring display characteristic amount, display, display system, measuring device, computer program, and storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve such a problem that in a sensor for measuring the display characteristic of a monitor, one for averaging an electric signal which light receiving element outputs with internal microcomputer exists, but a larger number of samplings is required as brightness is lower until the average of measured values is converged and it tends to take a longer measurement time, so that naturally, the measurement time is required to be set on the assumption that the brightness is lowest, because the measured value is not known before measurement and in certain instance, the measurement time is unnecessarily made long. <P>SOLUTION: When a characteristic amount related to the display of the monitor 1 is measured, the characteristic amount related to the display is estimated based on the definition information of an ICC profile, etc. stored in an image forming apparatus 2 and the measurement time optimum to measure a first characteristic amount is set in the sensor 3, to measure the characteristic amount related to the display by the measurement time. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a measurement method, a display system, a display device, a measurement device, a computer program, and a storage medium that optimize the time required to measure a characteristic amount related to display on a display device and reduce the total measurement time.

In the printing and design industry, work environments are being built that incorporate color management for the purpose of improving work efficiency, shortening delivery times, and reducing costs. Color management refers to performing color management consistently from upstream to downstream of work by combining color characteristics between different devices (cameras, display devices, printing machines, etc.). Since color characteristics depend on each device, even the same image is expressed in different colors. Therefore, in order to improve the efficiency of the entire work, such as eliminating the need for color adjustment at each stage of the work environment, it is required to manage the colors between these devices so that unified colors can be handled. become. In recent years, the introduction of “color management compatible monitors” for the purpose of confirming colors at work sites in the printing industry has become popular. The “color management compatible monitor” is a display device that displays the finish at the stage of each printing operation and enables the color to be confirmed on the screen.

Naturally, the performance of the "color management compatible monitor" is such that excellent color reproduction, smooth gradation expression, correct color temperature, luminance and color tone stability, etc. are obtained, and the display characteristics are always maintained. This is also an important factor. The operation of preparing the display environment of the monitor in order to maintain display characteristics is called calibration. In the calibration, the color characteristics of the “color management compatible monitor” are adjusted so that a necessary display state is obtained in accordance with the use environment, use contents, and deterioration due to aging.

Calibration is performed using sensors and software. The sensor measures the amount of light, converts it into an electrical signal, and transmits it to a personal computer. The sensor is placed on the screen of the display device that is the work target, or is placed at a distance. The software is installed in the personal computer, receives the measurement value from the sensor, and adjusts the output image signal from the personal computer or the control circuit in the display device so that the measurement value matches the target value. To do. Examples of adjustment targets include brightness, white point, gamma, and the like, and target values are individually set, and measurement and adjustment are repeated until the measured values by the sensors match the individual target values. Luminance refers to the brightness of the screen of the display device. By matching the brightness of the display device and the brightness of the printing paper, the consistency of the display image and the color of the print image is improved. The white point refers to a chromaticity point when white is displayed. Gamma refers to the luminance relationship between the image signal input to the display device and the image displayed on the actual screen, and smooth gradation expression can be achieved by adjusting this. FIG. 17 shows a graph of gamma characteristics. The X axis indicates the input gradation, that is, the gradation level of the image signal input to the display device, and the Y axis indicates the luminance of the image displayed on the screen of the display device when the image signal of that gradation level is input. Indicates. Ideally, the curve should be an exponential curve as shown in FIG. 17B, but is often distorted as shown in FIG. 17A due to variations in each circuit constituting the display device. . In the calibration, for example, the luminance in all gradations (0 to 255) is measured, and the display device is adjusted so that this becomes a curve as shown in FIG.

JP 2002-281931 A

FIG. 14 shows a system configuration example for calibration. The monitor 1 and the personal computer 2 are connected by a video cable 5, and image data generated by the personal computer 2 is transmitted to the monitor 1 via the video cable 5. Software for calibration (not shown) is installed in the personal computer 2, and a sensor 3 for calibration is connected by a USB cable 4. A control command for the sensor 3 output from the personal computer 2 and a measured value by the sensor 3 are exchanged via the USB cable 4. The sensor 3 is installed in close contact with the display surface of the monitor 1 or in front of the display surface.

An example of the internal configuration of the sensor 3 is shown in FIG. The light emitted from the monitor 1 is first condensed by the lens 31 of the sensor 3. The collected light is optically shaped by the optical filter 32 so as to be easily received by the light receiving element 33 at the subsequent stage, for example, removal of light in an unnecessary wavelength range. The light receiving element 33 converts the light into an electrical signal and outputs it to the microcomputer 34 at the subsequent stage. The microcomputer 34 converts the electrical signal from the light receiving element 33 into a digital signal or the like for transmission to a personal computer. The microcomputer 34 receives a control command from the personal computer and controls the start and end of measurement. The highest-stage communication circuit 35 is used for exchanging measurement values and control commands with the personal computer 2, and for example, a USB transmission / reception circuit is used.

As the light receiving element 33, a semiconductor such as a photodiode is used. It is known that such a device has a poor signal-to-noise ratio and low noise at low luminance, so that the output electric signal becomes unstable. In order to solve this problem, some microcomputers 34 average the electrical signal output from the light receiving element 33. However, the lower the luminance, the more samplings are required, and the measurement time tends to take longer. Naturally, since the measurement value is not known before the measurement, it is necessary to set a measurement time assuming the lowest luminance. In some cases, the measurement time is unnecessarily prolonged.

FIG. 15 shows temporal changes in the tristimulus values measured by the sensor. The tristimulus value is a value expressed by the color system (X, Y, Z) defined in the CIE 1931 color system (JIS Z 8701), and is a value obtained by quantifying the amount of stimulation received by the human eye. It is. FIG. 15 (a) shows a light emission brightness of 0.3 [cd / m ² ], and when measuring extremely dark light, FIG. 15 (b) shows 0.618 [cd / m ² ] slightly brighter than FIG. 15 (a). FIG. 15C shows the measurement data when measuring a brighter 11.802 [cd / m ² ] light. As is apparent from the figure, it can be seen that the time until the measured value stabilizes decreases as the brightness increases to 3 seconds, 1.3 seconds, and 1 second.

Some sensors output not only the tristimulus values but also chromaticity values. The chromaticity value is obtained from the ratio of each component value of tristimulus values and the sum of the component values, and corresponds to information that combines hue and saturation. As in FIG. 15, 0.3 [cd / m ² ] is shown in FIG. 16A, 0.618 [cd / m ² ] is shown in FIG. 16B, and 11.802 [cd / m ² ] is shown in FIG. The measurement data when measuring the light of] is shown. As for the chromaticity value, it can be seen that the time until the measurement value is stabilized decreases to 3 seconds, 1.3 seconds, and 1 second as the luminance increases.

Since the measurement result cannot grasp the measurement result in advance, it is assumed that the measurement result has low luminance, and a relatively long measurement time corresponding to this is set. For this reason, it took time for the measurement work, which was a factor in lengthening the entire calibration work.

The present invention has been made in view of such circumstances, and a measurement method, a display system, a display device, a measurement device, which sets an optimal measurement time for a sensor and measures a display characteristic amount in as short a time as possible, It is to provide a computer program and a storage medium.

A measuring method according to a first invention is a method for measuring a characteristic quantity related to display on a display device, wherein the first characteristic quantity related to display on the display device is obtained based on definition information related to display on the display device. Estimating, setting a measurement time based on the first characteristic amount, and measuring the second characteristic amount at the measurement time.

The measuring method according to a second invention is characterized in that, in the first invention, the first characteristic quantity and the second characteristic quantity are display luminances of the display device.

The measuring method according to a third invention is characterized in that, in the first invention, the first characteristic amount is a display luminance of the display device, and the second characteristic amount is a display chromaticity of the display device. And

The measurement method according to a fourth invention is characterized in that, in the first invention, the definition information is a profile for color management of the display device.

The measurement method according to a fifth aspect is characterized in that, in the first aspect, the definition information is an adjustment value stored in the display device.

A measuring apparatus according to a sixth aspect of the present invention is a first characteristic quantity estimating means for estimating a first characteristic quantity relating to display on the display device based on definition information relating to display on the display apparatus, and the first characteristic quantity. And a measurement time setting means for setting the measurement time based on the above.

A display system according to a seventh aspect of the present invention is a display system comprising: an image generation device that generates an image signal; and a display device that displays an image corresponding to the intensity of the input image signal on the display screen. Measuring means for measuring a second characteristic amount relating to the display, first characteristic amount estimating means for estimating a first characteristic amount relating to display of the display device based on definition information relating to display of the display device, and Measuring time setting means for setting a measuring time based on the first characteristic quantity.

According to an eighth aspect of the present invention, there is provided a display device for displaying an image corresponding to the intensity of an input image signal on a display screen, a measuring means for measuring a second characteristic amount related to display on the display screen, First characteristic amount estimating means for estimating a first characteristic amount related to display on the display device based on definition information related to display on the display device, and measurement for setting a measurement time based on the first characteristic amount And a time setting means.

A computer program according to a ninth aspect of the present invention is a computer program for causing a computer to function as measurement time setting means for setting a measurement time of a measurement device that measures a second characteristic amount related to display on a display device. A first characteristic amount estimating means for estimating a first characteristic amount related to display of the display device related to display from definition information related to display of the display device, and a measurement time based on the first characteristic amount It is made to function as a measurement time setting means for setting.

The storage which can be read by the computer according to the tenth invention records the computer program according to the ninth invention.

In the first invention, the sixth invention, the seventh invention, the eighth invention, the ninth invention, and the tenth invention, the definition information relating to the display of the display device, for example, information such as gradation characteristics and luminance, is used. A characteristic amount is estimated, an optimum time for measuring the characteristic amount of the display device is obtained based on the estimated characteristic amount, and the same or different characteristic amount as the above is measured at the obtained time. Since the measurement time is set to the minimum time required for measuring the characteristic quantity, the measurement work can be shortened.

In the second invention, the characteristic quantity of the display device to be estimated and measured is set as the display luminance. In calibration of a display device, there are adjustment items that require luminance measurement, such as luminance and gamma. By setting the minimum time required for measurement as the measurement time, the time required for measurement and adjustment of luminance and gamma can be suppressed, and the entire calibration work can be shortened.

In the third invention, the characteristic quantity of the display device to be estimated is the display luminance, and the characteristic quantity of the display device to be measured is the display chromaticity. The relationship between chromaticity and luminance is established through tristimulus values. Therefore, even when the estimated first characteristic quantity is different from the measured second characteristic quantity, it is possible to set the minimum time required for measurement as the measurement time.

In the fourth invention, a profile for color management such as an ICC (International Color Consortium) profile that defines the characteristics of the color space of the display device is used as definition information for estimating the characteristic amount. Among the characteristic information included in the ICC profile, the gamma coefficient and the display brightness at the maximum input gradation are information necessary for estimating the display brightness. Based on this information, the display brightness of the display device can be estimated, and the minimum required measurement time can be set based on the estimated display brightness.

In the fifth invention, the adjustment value stored in the display device is used as definition information for estimating the characteristic amount. Among the information included in the adjustment value, the gamma coefficient, the brightness adjustment value, and the like are information necessary for estimating the display luminance. Based on this information, the luminance to be measured can be estimated by the measuring apparatus, and the minimum measurement time can be set based on the estimated luminance.

In the present invention, a characteristic amount relating to display of the display device is estimated from definition information relating to display of the display device, for example, information such as gradation characteristics and luminance, and the same as the characteristic amount based on the estimated characteristic amount. Alternatively, an optimum time for measuring another characteristic amount is obtained, and the characteristic amount is measured at the obtained time. Since the measurement time is set to the minimum time required for measuring the characteristic quantity, the measurement work can be shortened.

It is the block diagram which showed the structure of the display system of Embodiment 1 which concerns on this invention. It is explanatory drawing which showed the content of the ICC profile. It is explanatory drawing which showed the content of the optimal measurement time information. It is the flowchart which showed the process sequence of the display system of Embodiment 1 which concerns on this invention. It is explanatory drawing which showed the content of the optimal measurement time information. It is the block diagram which showed the structure of the display system of Embodiment 2 which concerns on this invention. It is explanatory drawing which showed the content of the adjustment value. It is the flowchart which showed the process sequence of the display system of Embodiment 2 which concerns on this invention. It is the characteristic view which showed the relationship between Brightness adjustment value and light emission luminance. It is the flowchart which showed the process sequence of the display system of Embodiment 3 which concerns on this invention. It is the block diagram which showed the structure of the display apparatus of Embodiment 4 which concerns on this invention. It is the flowchart which showed the process sequence of the display apparatus of Embodiment 4 which concerns on this invention. It is the block diagram which showed the structure of the conventional sensor. It is explanatory drawing which showed the system configuration | structure for the conventional calibration. It is explanatory drawing which showed the time change of the tristimulus value measured value by the conventional sensor. It is explanatory drawing which showed the time change of the chromaticity measurement value by the conventional sensor. It is a characteristic view showing a gamma characteristic of a monitor.

Embodiment 1
DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a description will be given based on the drawings showing embodiments of the present invention. FIG. 1 is a block diagram showing a configuration of a display system according to Embodiment 1 of the present invention. The image generation apparatus 2 of the present invention using a computer such as a personal computer is a CD 21 that reads information from a recording medium such as a CPU 21 that controls the entire apparatus and a CD-ROM that records information such as a calibration program described later. An auxiliary storage unit 22 such as a ROM drive, a recording unit 23 such as a hard disk for recording information read by the auxiliary storage unit 22, a RAM 24 for temporarily storing information, and an input unit 25 such as a mouse and a keyboard are provided. The recording means 23 stores an ICC profile 23a corresponding to definition information for a display device, which will be described later, optimum measurement time information 23b for recording display brightness and measurement time in association with each other, and a calibration program 23c.

Various information such as a computer program and data for the present invention is read from the recording means 23, stored in the RAM 24, and executed by the CPU 21, whereby the personal computer operates as the image generating apparatus of the present invention.

The image generation apparatus 2 includes a graphics controller 26a that generates image data based on the image file, and an image signal output unit 26b such as a connector such as a DVI that outputs the image data generated by the graphics controller 26a as an image signal. A video card 26 is provided.

Further, the image generation apparatus 2 includes a communication control unit 27b such as a USB controller that controls communication defined by a standard such as USB, and a communication signal input / output unit such as a connector used for communication controlled by the communication control unit 27a. A communication board 27 having 27b is provided.

One end of a video cable that transmits an image signal is connected to the image signal output unit 26b included in the image generation apparatus 2, and one end of a communication line that transmits various types of information is connected to the communication signal input / output unit 27b. The other end of the communication line is connected to a monitor 1 such as a CRT display, a liquid crystal display, or a plasma display.

The monitor 1 includes an image signal input unit 14 such as a DVI connector for connecting the other end of the video cable for transmitting the image signal. The image signal input from the image signal input unit 13 is sent to the video circuit 12. The video circuit 12 displays an image based on the image signal on the display unit 11 such as an LCD.

FIG. 2 shows an example of recorded contents of the ICC profile corresponding to the definition information of the present invention. The ICC profile is stored in the storage unit 23 constituting the image generating apparatus 2 as definition information. The ICC profile includes a part indicating general information of ICC profile called Header Information and a part indicating characteristics of the target device called Tag Table. The size in the header information indicates the file size of the ICC profile, the version indicates the version of the standard conforming to the ICC profile, the device class indicates the type of device supported by the ICC profile, and the color space is used for the target device. PCS indicates the connection color space, Date indicates the creation date of the ICC profile, and Manufacturing indicates the manufacturer of the target device. On the other hand, rXYZ in the Tag Table indicates a standardized tristimulus value of red under a D50 light source. The D50 light source here refers to daylight with a color temperature of 5003 [K], and measurement under this light source is standard in the printing industry. Similarly, gXYZ in the Tag Table indicates a green standardized tristimulus value under a D50 light source, and bXYZ indicates a blue standardized tristimulus value under a D50 light source. RTRC in Tag Table indicates red gamma value, gTRC indicates green gamma value, bTRC indicates blue gamma value, wtpt indicates white standardized tristimulus value, chad indicates chromatic adaptation conversion Lumi represents the display luminance value of the monitor.

FIG. 3 is an example of the optimum measurement time information 23b stored in the storage unit 23 constituting the image generating apparatus 2. The estimated luminance value is stored for each 0.1 [cd / m ² ], and the optimum measurement time for measuring each estimated luminance value is stored in association with each other. As the optimum measurement time, the time until the measurement value converges is measured in advance for each luminance value, and this is stored in association with the luminance value. The storage form is not limited to that shown in FIG. 3, and only the threshold value and the optimum measurement time may be stored.

Next, processing in the display system of the present invention will be described. FIG. 4 is a flowchart showing the processing of the display system of the present invention. The operator starts measurement of a characteristic amount related to display such as a display luminance value emitted from the display unit 11 using the sensor 3 (S1). At the start of measurement, the operator installs the sensor 3 on the front surface of the display unit 11 and activates a calibration program 23 c stored in the storage unit 23.

The program 23c instructs the CPU 21 to output a calibration image to the monitor 1, and the display luminance value emitted from the monitor 1 to which the gradation value of the image is input is stored in the storage means 23 in the ICC profile. 23a is estimated (S2). Upon receiving the instruction from the program 23c, the CPU 21 outputs a corresponding image signal from the video card 26, and the image signal is input to the monitor 1 through the video cable.

The program 23c reads the optimum measurement time for measuring the display luminance value estimated in S2 from the optimum time information 23b stored in the storage unit 23, and instructs the CPU 21 to transmit it to the sensor 3. (S3). As shown in FIG. 3, the optimum time information 23b stores the estimated luminance value and the optimum time in association with each other, and the program 23c reads the associated measurement time. The setting of the measurement time is not limited to storing such a correspondence table, and a calculation formula for calculating the optimum measurement time from the luminance value may be prepared in advance, and the optimum measurement time may be obtained from the calculation formula. . The CPU 21 that has received an instruction from the program 23c converts the read optimum measurement time into a communication signal, and transmits the communication signal from the communication board 27 to the sensor 3 via the USB cable, thereby setting the measurement time in the sensor 3. Communication is not limited to USB, but may be wired communication means such as RS232C or wireless communication means such as IEEE 812.11.

Since the configuration of the sensor 3 of the present invention is the same as the conventional configuration shown in FIG. The sensor 3 receives the optimum measurement time via the USB cable in the communication circuit 35, and the microcomputer 34 performs measurement with the received optimum measurement time (S4). The microcomputer 34 stores an electric signal indicating the amount of received light output from the light receiving unit 33 every predetermined time (shorter than the optimum measurement time), and repeats this during the optimum measurement time. After the optimum measurement time has elapsed, an average value is obtained from the stored plurality of received light amounts, and this is used as a measured luminance value. The measured luminance value determined by the microcomputer 34 is converted into a communication signal and transmitted from the communication circuit 35 to the image generation device 2 via the USB cable.

The measured luminance value transmitted from the sensor 3 is received by the communication board 27, and the program 23c compares the received measured luminance value with the luminance value estimated in S2, and obtains the difference (S5). If the difference is too large, the measurement time is reset and the measurement is re-executed (S6). Specifically, the received measurement luminance value is regarded as an estimated luminance value, and the optimum measurement time corresponding to this is read from the optimum measurement time information 23b stored in the storage means 23, and this is set as a new measurement time. Alternatively, only a predetermined time may be added or subtracted. In the determination of S5, a condition such that the difference is 10% of the measured luminance value is set in advance.

If there is no large difference in the difference in S6, the measurement by the sensor 3 is terminated (S7). When the processing from S1 to S7 is completed, the program 23c outputs an image of a different gradation to the monitor 1, and re-executes the processing from S1 to S7. If measurement is performed for each gradation, the processing from S1 to S7 is repeated 256 times.

In the above-described embodiment, the display luminance value is a measurement target. However, the present invention is not limited to this, and a value related to other display characteristics such as xy chromaticity, tristimulus values XYZ, CIELAB, and spectral distribution may be measured. In that case, the display characteristic value required for determining the measurement time is estimated from the ICC profile 23a stored in the storage means 23, and the optimum measurement time information 23b corresponds to the estimated characteristic value estimated display characteristic value and the optimum measurement time. It will be remembered. The sensor 3 needs to have an optical configuration and an electric circuit capable of measuring each display characteristic value.

A method for estimating the display luminance value from the ICC profile will be described. As shown in FIG. 2, the luminance value of the monitor 1 is described as Lumi in the Tag Table of the ICC profile. In addition, gamma coefficients for R (red), G (green), and B (blue) are described as rTRC, gTRC, and bTRC, respectively. The luminance value Y with respect to the input gradation value X can be calculated by the following formula using the maximum luminance value Ymax and the gamma coefficient γ.

Y = Ymax × X ^γ (Equation 1)
When measuring the gamma characteristics of RGB single colors, the luminance can be estimated by the following equation according to Equation 1.

Estimated luminance value Y _R = ^Rumi value × R distribution ratio R _R X ^{rTRC value in} R single color (Equation 2)
Estimated brightness value Y _G = Lumi value × G distribution ratio R _G × X ^{gTRC value in} G single color (Equation 3)
Estimated luminance value Y _B = ^Bumi value × B distribution ratio R _B × X ^{bTRC value in} B single color (Equation 4)
Since Lumi described in the ICC profile 23a is a luminance value obtained by adding the RGB colors, the luminance of each color is obtained from the distribution ratios R _R , R _G , and R _B , and then Equations 2, 3, and 4 are used. Brightness estimation. As described above, in the ICC profile, standardized tristimulus values of each color are described as rXYZ, bXYZ, and gXYZ. Among the described values, Y indicates luminance, and therefore, the Y ratio of each color is used as the luminance distribution ratio. When measuring the gamma characteristic in white, the luminance estimation can be calculated from the sum of Equation 2, Equation 3, and Equation 4 as in the following equation.
Estimated brightness value in white Y _K = Estimated brightness value in R single color Y _R + G Estimated brightness value in single color Y _G + B Estimated brightness value in single color Y _B (Equation 5)

The ICC profile, while others gamma coefficient kTRC have been described with respect to white, in that case it is possible to calculate the estimated luminance value Y _K in white by the following equation.
Estimated luminance value in white Y _K = Lumi value × X ^{kTRC value} (Equation 5)

FIG. 5 shows another example of the optimum measurement time information 23b. The estimated luminance value is stored every 0.1 [cd / m ² ], and the optimum measurement time for measuring each estimated luminance value is stored in association with each other. The measurement time is stored for three patterns of the fastest mode, standard mode, and high definition mode. In the case of the fastest mode, as shown in the drawing, 3 seconds when 1 [cd / m ² ] or less, ² seconds when 1.1 [cd / m ² ] or more and 10 [cd / m ² ] or less, 10.1 [cd / m] ² ] or more and 30 [cd / m ² ] or less is associated with 1.5 seconds, and 30.1 [cd / m ² ] or more is associated with 1 second. In the case of the standard mode, 3 seconds are associated with 1 [cd / m ² ] or less, and ² seconds are associated with 1.1 [cd / m ² ] or more. In the high accuracy mode, 5 seconds are associated with 4 [cd / m ² ] or less, and ² seconds are associated with 4.1 [cd / m ² ] or more. In the fastest mode, the total measurement time is shortened by finely setting the measurement time to the minimum required time. On the other hand, in the high accuracy mode, by taking a long measurement time, measurement errors due to insufficient measurement time are avoided, and accurate measurement is achieved. Switching between the modes may be performed by an instruction to the program 23c by the operator, or from the number of days elapsed since the previous measurement, the high-precision mode when the elapsed time is long, and the high-speed mode when the elapsed time is short. Thus, the program 23c may be switched automatically. Further, the storage form is not limited to that shown in FIG. 5, and only the threshold value and the optimum measurement time may be stored for each mode.

Embodiment 2
Hereinafter, a description will be given based on the drawings showing other embodiments of the present invention. FIG. 6 is a block diagram showing the configuration of the display system according to Embodiment 2 of the present invention. The monitor 1 has a communication signal input / output unit 16a such as a connector for connecting the other end of a communication line such as a USB cable, a communication circuit 16 having a communication control unit 16b such as a USB controller, and an adjustment input for accepting adjustment of brightness and the like by an operator. The storage unit 17 stores the adjustment values received from the unit 15 and the adjustment input unit 15. Various information received from the communication signal input / output unit 16 is sent to a control circuit 13 such as a microcomputer, and the control circuit 13 controls various processes and the video circuit 12 based on the received information. It is also possible to output various adjustment values stored in the storage unit 17 from the communication signal input / output unit 16a to the outside. Since other configurations are the same as those of the first embodiment, the same reference numerals are given and the description thereof is omitted.

FIG. 7 shows an example of the contents of the adjustment value corresponding to the definition information of the present invention. The adjustment value is stored in the storage means 17 constituting the monitor 1 as definition information. The adjustment value includes a screen adjustment group related to image quality and a color adjustment group related to display color. Clock in the Screen adjustment group indicates the sampling frequency when sampling the input analog image signal, and Phase indicates the phase of the clock signal when sampling the input analog image signal. The Color adjustment group includes a Brightness adjustment value indicating an adjustment value for luminance adjustment, a Gamma adjustment value indicating an adjustment value for gamma coefficient adjustment, and a saturation adjustment value such as Saturation.

Next, processing in the display system of the present invention will be described. FIG. 8 is a flowchart showing the processing of the display system of the present invention. The operator starts measurement of a characteristic amount related to display such as a display luminance value emitted from the display unit 11 using the sensor 3 (S21). At the start of measurement, the operator installs the sensor 3 on the front surface of the display unit 11 and activates the calibration program 23 c stored in the storage unit 23.

The program instructs the CPU 21 to output a calibration image to the monitor 1, reads the adjustment value 17 a stored in the monitor 1, and the display luminance value emitted by the monitor 1 to which the gradation value of the image is input. Is estimated (S22). Upon receiving an instruction from the program, the CPU 21 outputs a corresponding image signal from the video card 26, and the image signal is input to the monitor 1 via the video cable. Thereafter, the same processing as in the first embodiment is executed.

A method for estimating the display luminance value from the adjustment value will be described. The adjustment value 17a stored in the monitor 1 includes a Brightness adjustment value indicating an adjustment value for luminance adjustment. The Brightness adjustment value is normally the maximum value that can be adjusted, and if the monitor 1 is a liquid crystal monitor, the adjustment value that causes the backlight to emit light to the maximum is 100%, and can be adjusted between 0% and 100%. . FIG. 9 is a characteristic diagram of Brightness adjustment value and luminance. Although the luminance changes approximately linearly with respect to the Brightness adjustment value, the output is saturated near the maximum luminance due to circuit factors, and there is a region where the luminance does not increase as illustrated. The Brightness adjustment value when reaching an area where the luminance does not increase is Bmax [%], and the luminance at that time is Lmax [cd / m ² ]. Also, the luminance value when the Brightness adjustment value is 0 [%] is Lmin [cd / m ² ]. If the current Brightness adjustment value is Bc [%], the luminance value Lc [cd / m ² ] at that time can be obtained from the following equation.
Lc = (Lmax−Lmin) × Bc / Bmax + Lmin (Equation 6)

Bmax [%], Lmax [cd / m ² ], and Lmin [cd / m ² ] may be measured in advance in the manufacturing process, and may be stored in the storage unit 17 of the monitor 1, or the previous calibration by the program 23c. It is sometimes measured and stored in the storage means 23 of the image generating apparatus 2. Moreover, when measuring the white gamma characteristic, it can obtain | require from the following formula | equation using Gamma in an adjustment value.
Estimated luminance value in white Y _K = Lc × X ^Gamma ... (Expression 7)

Embodiment 3
Hereinafter, a description will be given based on the drawings showing other embodiments of the present invention. Since the configuration of the display system is the same as that of the display system according to the second embodiment shown in FIG. 6, the same reference numerals are given and description thereof is omitted. FIG. 10 is a flowchart showing the processing of the display system of the present invention. The operator starts the measurement of the characteristic amount related to the display such as the display luminance value emitted from the display unit 11 using the sensor 3 (S31). At the start of measurement, the operator installs the sensor 3 on the front surface of the display unit 11 and activates a calibration program 23 c stored in the storage unit 23.

The program 23c instructs the CPU 21 to output an image for calibration to the monitor 1, and confirms whether the ICC profile 23a is stored in the storage unit 23 of the image generation apparatus 2 (S32). The ICC profile 23a is normally created by the calibration program 23c from the measurement result after calibration. The ICC profile is deleted at the first calibration or for other reasons, and stored in the image generating apparatus 2. In some cases, the means 23 does not exist. In the present embodiment, the presence of the ICC profile 23a is confirmed, and if there is, the display luminance value is estimated from the ICC profile 23a (S33). If not, the display is made from the adjustment value 17a stored in the storage means 17 of the monitor 1. The luminance value is estimated (S34). Since the display luminance estimation method and the subsequent processing are the same as those in the first and second embodiments, the description thereof will be omitted.

Embodiment 4
Hereinafter, a description will be given based on the drawings showing other embodiments of the present invention. FIG. 11 is a block diagram showing a configuration of the monitor 1 according to the fourth embodiment of the present invention. The monitor 1 includes an image signal input unit 14 such as a DVI connector that connects the other end of the video cable for transmitting the image signal, an adjustment input unit 15 that receives adjustment of brightness and the like by the operator, and an adjustment received from the adjustment input unit 15 A storage unit 17 for storing values and an OSD generation unit 18 for generating OSD images are provided. The image signal input from the image signal input unit 14 is sent to the video circuit 12, and the video circuit 12 displays an image based on the image signal on the display unit 11 such as an LCD. When there is an OSD image output from the OSD generation unit 18, the video circuit 12 superimposes the input image signal on the display unit 11 to display it. OSD is an abbreviation for On Screen Display, and refers to an operation screen for performing various adjustments of the device or its function. The monitor 1 is further provided with a sensor 3 near the display unit 11, and the measurement result is transmitted to the control circuit 13 of the monitor 1. The configuration inside the sensor 3 is the same as that shown in FIG.

Next, processing in the monitor 1 of the present invention will be described. FIG. 12 is a flowchart showing the processing of the display system of the present invention. The monitor 1 starts measurement of the characteristic amount related to the display such as the display luminance value emitted from the display unit 11 using the sensor 3 (S41). The start of measurement may be instructed by the operator via the adjustment input unit 15, or may be timed by a timer (not shown) and started when a predetermined time is reached. Since the sensor 3 is installed in the vicinity of the display unit 11 in advance, it is not necessary for the operator to install the sensor 3 on the front surface of the display unit 11.

The control circuit 13 instructs the OSD generation unit 18 to output a calibration image, reads the adjustment value 17a stored in the monitor 1, and estimates the display luminance value emitted by the display unit 11 (S42). The calibration image output from the OSD generation unit 18 refers to an image required for adjustment such as R, G, B single color, white color, etc. on the area measured by the sensor 3 or the entire display unit 11. The OSD generation unit 18 plays a role corresponding to the video card 26 in the first to fourth aspects. Thereafter, the same processing as in the second embodiment is executed.

In the fourth embodiment, the estimated luminance value is obtained from the adjustment value 17a stored in the monitor 1. However, the present invention is not limited to this, and a circuit for external communication is provided in the monitor 1, and an ICC profile is obtained from a personal computer or the like. Such definition information may be written in the storage means 17 in the monitor 1, and the estimated luminance value may be obtained based on this. In the fourth embodiment, the OSD generation unit 18 is diverted to output a calibration image. However, the present invention is not limited to this, and a dedicated circuit that generates only the calibration image may be provided.

In the second to fourth embodiments, the display luminance value is estimated using only the Brightness adjustment value indicating the adjustment value for luminance adjustment, which is the adjustment value of the monitor. However, the present invention is not limited to this, and the luminance, contrast, gamma characteristic, A display characteristic value may be estimated by combining a plurality of monitor adjustment values such as a gain and a matrix, and an optimum measurement time may be obtained.

In the first to fourth embodiments, the definition information is described as an ICC profile. However, the definition information is not limited to this, and any file that defines the color characteristics of the display device may be used. For example, if WCS (Windows (registered trademark) Color System) profile proposed by Microsoft Corporation, ColorSync profile proposed by Apple Inc., or any other original standard that defines the color characteristics of the display device, It can be used as definition information of the present invention.

In the first to fourth embodiments, the optimum measurement time is obtained based on the estimated luminance value estimated from the definition information or the like. However, the present invention is not limited to this, and a correction value that takes into account the aged deterioration to the estimated luminance value estimated from the definition information or the like And the optimum measurement time may be obtained based on the result of integration. Or you may make it integrate the correction value which considers aged deterioration to the optimal measurement time based on the estimated luminance value estimated from the definition information etc.

In the above-described embodiment, the sensor is described as outputting measurement luminance. However, the present invention is not limited to this, and other measurement values such as a spectral distribution may be output. The method for determining the measurement value is not limited to the addition average, and a moving average or the like may be used.

DESCRIPTION OF SYMBOLS 1 Monitor 11 Display part 12 Video circuit 13 Control circuit 14 Image signal input part 15 Adjustment input part 16 Communication circuit 16a Communication line input / output part 16b Communication control part 17 Storage means 17a Adjustment value 18 OSD generation part 2 Image generation apparatus 21 CPU
22 Auxiliary storage unit 23 Storage unit 23a ICC profile 23b Optimal measurement time information 23c Program 26 Video card 26a Graphic controller 26b Image signal output unit 27 Communication board 27a Communication control unit 27b Communication signal input / output unit 3 Sensor 31 Lens 32 Optical filter 33 Light receiving element 34 Microcomputer 35 Communication circuit 35a Communication control unit 35b Communication signal input / output unit

Claims (10)

A method for measuring a characteristic amount related to display on a display device, wherein a first characteristic amount related to display on the display device is estimated based on definition information related to display on the display device, and the first characteristic amount is obtained. A characteristic amount measuring method related to display, characterized in that a measurement time is set based on the second characteristic amount measured at the measurement time. The method for measuring a characteristic amount related to display according to claim 1, wherein the first characteristic amount and the second characteristic amount are display luminances of the display device. The display-related characteristic amount according to claim 1, wherein the first characteristic amount is display luminance of the display device, and the second characteristic amount is display chromaticity of the display device. Measuring method. The method of measuring a characteristic amount related to display according to claim 1, wherein the definition information is a profile for color management of the display device. The method for measuring a characteristic amount related to display according to claim 1, wherein the definition information is an adjustment value stored in the display device. In a measurement device that measures a characteristic amount related to display on a display device, based on definition information related to display on the display device, characteristic amount estimation means for estimating a characteristic amount related to display on the display device, and based on the characteristic amount And a measurement time setting means for setting the measurement time. In a display system including an image generation device that generates an image signal and a display device that displays an image corresponding to the intensity of the input image signal on a display screen, a second characteristic amount related to display on the display screen is measured Based on definition information relating to display on the display device, first characteristic amount estimating means for estimating a first characteristic amount relating to display on the display device, and on the basis of the first characteristic amount A display system comprising measurement time setting means for setting a measurement time. In a display device that displays an image corresponding to the intensity of the input image signal on a display screen, measurement means for measuring a second characteristic amount related to display on the display screen, and definition information related to display of the display device And a first characteristic amount estimating unit that estimates a first characteristic amount related to display on the display device, and a measurement time setting unit that sets a measurement time based on the first characteristic amount. Display device. A computer program for causing a computer to function as measurement time setting means for setting a measurement time of a measurement device that measures a second characteristic amount related to display on a display device, the computer relating to display on the display device First function amount estimating means for estimating a first characteristic amount related to display on the display device from definition information, and measurement time setting means for setting a measurement time based on the first characteristic amount A featured computer program. A computer-readable storage medium in which the computer program according to claim 9 is recorded.