JP2012247285A - Photometric apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photometric apparatus which is capable of accurately measuring a crosstalk value.SOLUTION: A photometric apparatus comprises a light receiving section 12 which receives light from a measuring target (50), an arithmetic control section 31 which calculates a colorimetric value on the basis of the quantity of light acquired in the light receiving section 12, a first processing section (37) which generates reference colorimetric value data at a first predetermined time T1 on the basis of a signal from the light receiving section 12 corresponding to the quantity of acquired light, and a second processing section (39) which generates waveform data at a second predetermined time T2 on the basis of the signal from the light receiving section 12 corresponding to the quantity of acquired light. The arithmetic control section 31 calculates a ratio of a smaller maximal value to a larger maximal value in the waveform data from the second processing section and calculates the colorimetric value by multiplying a reference colorimetric value based on the colorimetric value data from the first processing section with the calculated ratio of the smaller maximal value.

Description

  The present invention relates to a photometric device for measuring light from a measurement object, and more particularly to a photometric device capable of accurately measuring luminance that changes in a short time.

  Conventionally, in order to grasp the quality of an image on a display, it has been considered to measure the display using a photometric device (see Patent Document 1). This photometric device has a function as a color meter, and it is possible to grasp the display quality by measuring the color of the display (its image) and grasping the display characteristics of the display.

  By the way, in recent years, a display capable of displaying an image in three dimensions (hereinafter referred to as a stereoscopic display) has appeared. In this case, the viewer recognizes it as a three-dimensional image by alternately acquiring the right eye image for the viewer's right eye and acquiring the left eye image for the left eye in a very short time. There is something to make. In such a stereoscopic display, so-called crosstalk that causes an image for the other eye to be acquired in one eye of the viewer may occur. Since this crosstalk becomes unnecessary light (display signal for an image) for the viewer, the quality of the image on the stereoscopic display is deteriorated. For this reason, in a stereoscopic display, it is desired to reduce the strength of crosstalk, that is, the crosstalk value in order to improve quality. Accordingly, a photometric device capable of accurately measuring the generated crosstalk value is desired.

JP 2009-3000257 A

  Here, in the photometric device having the function as the colorimeter described above, it is difficult to measure the temporal change in the intensity of light at short time intervals, so the display of the left and right images is repeated in a very short time. It is difficult to measure the crosstalk value generated in the inside. For this reason, it is conceivable to measure the crosstalk value using a photometric device having a function as a responsiveness detector capable of measuring a temporal change in light intensity at a short time interval.

  However, in such a photometric device (responsiveness detector), it is difficult to satisfy the accuracy required as a luminance meter because the resolution of the signal to be output according to the acquired light amount is not sufficient. There was room for improvement to use as an accurate measure of the talk value.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a photometric device capable of accurately measuring a crosstalk value.

  The photometric device according to the first aspect of the invention includes a light receiving unit that receives light from a symmetrical object, a calculation control unit that calculates a colorimetric value based on the light amount acquired by the light receiving unit, and an acquired light amount. A first processing unit that generates reference colorimetric value data at a first predetermined time based on a signal from the light receiving unit that responds, and a second predetermined time based on a signal from the light receiving unit that corresponds to the acquired light amount. A second processing unit that generates waveform data, wherein the calculation control unit calculates a ratio of a small maximum value to a large maximum value in the waveform data from the second processing unit, and from the first processing unit The colorimetric value is calculated by multiplying a reference colorimetric value based on the colorimetric value data by a ratio of the calculated small maximum value.

  The invention according to claim 2 is the photometric device according to claim 1, wherein the light receiving unit outputs an analog signal having a magnitude corresponding to the amount of received light, and the second processing unit is the light receiving unit. A second analog-to-digital conversion unit having a processing speed for storing waveform information in the analog signal from the analog signal from the light receiving unit. It has the 1st analog-digital conversion part with high resolution | decomposability with respect to the magnitude | size of a signal, It is characterized by the above-mentioned.

  A third aspect of the present invention is the photometric apparatus according to the second aspect, wherein the second analog-digital conversion unit is built in the arithmetic control unit.

  A fourth aspect of the present invention is the photometric device according to the second or third aspect, wherein the first analog-digital conversion unit is provided separately from the arithmetic control unit. To do.

  A fifth aspect of the present invention is the photometric device according to any one of the first to fourth aspects, wherein the second predetermined time period is at least two large maximum values and at least two small values. In order to be able to generate the waveform data including the maximum value, the waveform data is set according to the output characteristic of the measurement object.

  A sixth aspect of the present invention is the photometric device according to any one of the first to fifth aspects, wherein the calculation control unit starts the second predetermined time from the start of the second predetermined time. A measurement range signal indicating a period until the end point of is reached is generated.

  According to a seventh aspect of the invention, there is provided a program according to a seventh aspect, wherein a light receiving unit that receives light from a symmetrical object, a calculation control unit that calculates a colorimetric value based on the light amount acquired by the light receiving unit, and the acquired light amount. A first processing unit that generates reference colorimetric value data at a first predetermined time based on a signal from the light receiving unit, and a waveform at a second predetermined time based on a signal from the light receiving unit according to the acquired light amount A function of calculating a ratio of a small maximum value to a large maximum value in the waveform data from the second processing unit in the calculation control unit of a photometric device including a second processing unit that generates data; And a function of calculating the colorimetric value by multiplying a reference colorimetric value based on the colorimetric value data from the processing unit by the ratio of the calculated small maximum value.

  According to the photometric device of the present invention, the luminance value is calculated as an absolute value (reference luminance value) based on the reference colorimetric value data, and the relative relationship between luminance values based on the waveform data (display signal that is originally required) The crosstalk value is calculated from the relative relationship using the absolute value as a reference, so that the crosstalk value can be accurately measured.

  In addition to the above-described configuration, the light receiving unit outputs an analog signal having a magnitude corresponding to the amount of received light, and the second processing unit has a processing speed that stores waveform information in the analog signal from the light receiving unit. A first analog-to-digital converter having a higher resolution with respect to the magnitude of the analog signal from the light-receiving unit than the second analog-to-digital converter; A high-precision luminance value is calculated as an absolute value (reference luminance value) based on the reference colorimetric value data obtained through the first analog-digital conversion unit having a high resolution, and the high-speed Relative to luminance values based on the waveform data obtained through the second analog-digital converter having a high processing speed (crosstalk value with respect to the display signal originally required) Ratio) is calculated, since it is intended to calculate the crosstalk value from the relative relationship that the absolute value as a reference, it is possible to obtain an accurate cross-talk values.

  In addition to the above-described configuration, if the second analog-digital conversion unit is built in the arithmetic control unit, analog-digital conversion in the second analog-digital conversion unit can be performed at higher speed. Therefore, the ratio of the small maximum value to the large maximum value in the measurement light can be obtained more accurately based on the waveform data for the second predetermined time.

  In addition to the above-described configuration, if the first analog-digital conversion unit is provided separately from the calculation control unit, the first analog-digital conversion unit may have a calculation control unit incorporating the analog-digital conversion unit. The present invention can be applied to an existing photometric device only by providing a first analog-digital conversion unit having a higher resolution than the analog-digital conversion unit and changing a calculation processing method (program for that) in the calculation control unit. .

  In addition to the configuration described above, the second predetermined time period may include the waveform data including at least two large maximum values and at least two small maximum values in the measurement symmetric object. If it is set according to the output characteristics, it is possible to extract two or more peak values at a large maximum value (a display signal that is originally required), and 2 peak values at a small maximum value (crosstalk). Since two or more can be extracted, the ratio of the small maximum value to the large maximum value in the display signal (measurement light) can be obtained more accurately.

  In addition to the above-described configuration, when the calculation control unit generates a measurement range signal indicating a period from the start time of the second predetermined time to the end time of the second predetermined time, The user can easily grasp the correlation with the analog signal based on the amount of light acquired by the unit.

It is explanatory drawing which shows a mode that the stereoscopic vision image system 50 as a measuring object is measured using the photometry apparatus 10 which concerns on this invention. In order to explain the relationship between the display signal from the stereoscopic display 51 and the stereoscopic glasses 52 in the stereoscopic image system 50, the horizontal axis is the time axis, and the vertical axis is the display signal intensity (luminance). (A) shows a display signal output from the stereoscopic display 51, (b) shows a display signal that has passed through the right-eye lens portion 52a of the stereoscopic glasses 52, c) shows a display signal that has passed through the lens portion 52a on the left eye side of the stereoscopic glasses 52. It is explanatory drawing which shows the outline | summary of a structure of the photometry apparatus 10 which concerns on this invention. It is a flowchart which shows the measurement processing content of the crosstalk value (colorimetric value) performed by the calculation control part 31 (program stored in the memory | storage part 40). The relationship between the second predetermined time T2 with respect to the analog signal output from the CCD analog PCB 38 (light receiving unit 12) and the output measurement range signal Sm, the horizontal axis is the time axis, and the vertical axis is the light intensity (luminance). It is explanatory drawing shown by. The relationship between the analog signal output from the CCD analog PCB 38 (light receiving unit 12) and the digital signal converted by the second A / D converter 39 at the set second predetermined time T2 is represented by time on the horizontal axis. It is explanatory drawing which makes an axis | shaft and shows a vertical axis | shaft with the intensity | strength (luminance) of light.

  Embodiments of a photometric device according to the present invention will be described below with reference to the drawings.

  FIG. 1 is an explanatory diagram showing a state in which a stereoscopic image system 50 as a measurement object is measured using a photometric device 10 according to the present invention. 2 illustrates the relationship between the display signal from the stereoscopic display 51 and the stereoscopic glasses 52 in the stereoscopic image system 50, with the horizontal axis as the time axis and the vertical axis as the display signal. (A) shows the display signal output from the stereoscopic display 51, and (b) shows the display signal that has passed through the right-eye lens portion 52a of the stereoscopic glasses 52. (C) shows a display signal that has passed through the lens portion 52a on the left eye side of the stereoscopic glasses 52. FIG. 3 is an explanatory diagram showing an outline of the configuration of the photometric device 10 according to the present invention. In FIGS. 2B and 2C, the crosstalk (crosstalk value that is the luminance value) is shown by a two-dot chain line for easy understanding, but this magnitude is not necessarily the same as the actual output. It doesn't match.

  The photometric device 10 measures photometric characteristics (colorimetric values (luminance, chromaticity, color temperature)) of a measurement object. Examples of the measurement object include a display, a liquid crystal panel, a signal lamp, a cold cathode tube, an induction lamp, and an LED. In this embodiment, as shown in FIG. 1, a stereoscopic image system 50 that can be recognized by a viewer as a stereoscopic image is used as a measurement object.

  The stereoscopic image system 50 allows the viewer to stereoscopically obtain a right eye image for the viewer's right eye and a left eye image for the left eye alternately in a very short time. Recognize as an image. The stereoscopic image system 50 includes a stereoscopic display 51 (3D (three-dimensional) display) that is a display, and stereoscopic vision glasses 52.

  The stereoscopic display 51 alternately outputs a display signal for displaying a right-eye image and a display signal for displaying a left-eye image at predetermined time intervals (FIG. 2A). )reference). Note that the display signal here means light output from the display screen (each pixel thereof) as a light source in order to form a predetermined image on the display screen of the stereoscopic display 51. In this embodiment, the stereoscopic display 51 outputs a display signal for displaying a right-eye image and outputs a display signal for displaying the next left-eye image, that is, a pair for a stereoscopic image. The display signal output is set to one cycle, and the lighting frequency is set to 120 [Hz]. For this reason, in this embodiment, the stereoscopic display 51 outputs a pair of display signals for a stereoscopic image at a pace of about 8.3 [msec] (see FIG. 6).

  The stereoscopic glasses 52 have lens portions 52a that make a pair corresponding to the left and right, respectively, in the same manner as general glasses. In the stereoscopic glasses 52, it is possible to switch between the state in which both lens portions 52a transmit light and the state in which light is blocked in synchronization with the output of the left and right display signals on the stereoscopic display 51. Has been. Both lens portions 52a can be shielded by using, for example, a liquid crystal shutter. The stereoscopic glasses 52 are driven in synchronism with the display of the right-eye image and the left-eye image on the stereoscopic display 51, so that the right-eye lens unit 52a and the left-eye lens unit 52a Are alternately shielded at predetermined time intervals.

  Therefore, when viewing the stereoscopic display 51 through the right-eye lens portion 52a of the stereoscopic glasses 52, the display signal corresponding to the right-eye image among the display signals output from the stereoscopic display 51. Only can be acquired (see FIG. 2B). Further, when viewing the stereoscopic display 51 via the left eye side lens portion 52a of the stereoscopic glasses 52, only the display signals corresponding to the left-eye image among the display signals output from the stereoscopic display 51 are displayed. Can be obtained (see FIG. 2C).

  Accordingly, in the stereoscopic image system 50, the stereoscopic display 51 is shown through the stereoscopic glasses 52, so that the viewer can recognize the stereoscopic image. In the stereoscopic glasses 52, among the images for both eyes displayed alternately on the stereoscopic display 51, the right-eye lens unit 52a can acquire only the right-eye image (display signal). In addition, the lens unit 52a on the left eye side only needs to be able to acquire only the image (display signal) for the left eye, and is not limited to the present embodiment.

  As shown in FIG. 3, the photometric device 10 includes an optical system 11, a light receiving unit 12, and a circuit unit 13. The optical system 11 guides light from the measurement object to the light receiving unit 12 and the like. In this embodiment, the optical system 11 includes a collimation optical system 14 and a photometric optical system 15.

  The collimating optical system 14 is provided for visually recognizing a measurement location on the measurement object and adjusting the measurement location. The collimating optical system 14 includes an objective lens 16, an aperture mirror 17, a reflection mirror 18, a first lens 19, a second lens 20, and an eyepiece lens 21.

  The objective lens 16 is provided to collect measurement light emitted from the measurement object, and its focal position is set in the vicinity of the aperture mirror 17. For this reason, the measurement light emitted from the measurement object travels through the objective lens 16 to the aperture mirror 17.

  The aperture mirror 17 is provided to divide the measurement light collected by the objective lens 16 into light traveling to the collimating optical system 14 side and light traveling to the photometry optical system 15 side, and the opening 17a. Have. The aperture mirror 17 reflects part of the measurement light condensed by the objective lens 16 toward the reflection mirror 18 (collimation optical system 14), and the other part from the opening 17a to a third lens 23 (photometry) described later. Advance to optical system 15).

  The reflection mirror 18 reflects incident light. Therefore, the measurement light reflected by the aperture mirror 17 is reflected by the reflection mirror 18 and proceeds to the first lens 19.

  The first lens 19 constitutes a relay lens in cooperation with the second lens 20 and relays the image of the measurement object to the conjugate position 22. In the collimation optical system 14, the eyepiece 21 is provided so that the conjugate position 22 is the focal position. For this reason, the collimating optical system 14 relays the image of the measurement object to the conjugate position 22 by passing the measurement light reflected by the reflection mirror 18 through the first lens 19 and the second lens 20, and the eyepiece lens. The image of the measurement object can be collimated by the measurer via 21.

  The photometric optical system 15 is for appropriately adjusting the light from the measurement object and leading it to the light receiving unit 12. The photometric optical system 15 includes an objective lens 16 and an aperture mirror 17 shared with the collimating optical system 14, and a third lens 23, a color filter turret plate 24, a dark filter 25, a fourth lens 26, and a dark filter. A turret plate 27 is provided.

  The third lens 23 forms a relay lens in cooperation with the fourth lens 26, and relays an image of the measurement object to the light receiving unit 12 (its light receiving surface). In the photometric optical system 15, the other part of the measurement light collected by the objective lens 16 that has passed through the opening 17 a of the aperture mirror 17 passes through the third lens 23 to the color filter turret plate 24.

  The color filter turret plate 24 corrects the sensitivity of each wavelength. The color filter turret plate 24 includes a disk member 24a and a drive unit 24b having an output shaft connected to the central axis thereof. In the disk member 24a, a plurality of openings (four in the example shown in FIG. 3) are provided around the central axis, and filters having sensitivity to different wavelengths are provided in the four openings 24c, 24d, 24e, and 24f. It has been. The drive part 24b adjusts the rotation posture of the disk member 24a, and is constituted by a pulse motor in this embodiment. The color filter turret plate 24 has an opening (24c, 24d, 24e, 24f) on the optical path (measurement optical path) from the third lens 23 toward the neutral density filter 25, depending on the rotational posture of the disk member 24a. It is possible to exist in a position. For this reason, the color filter turret plate 24 can correct the sensitivity of a predetermined wavelength with respect to the measurement light that has passed through the third lens 23. In the color filter turret plate 24, the rotational position of the disk member 24a is adjusted by appropriately driving the driving unit 24b under the control of the arithmetic control unit 31 described later, that is, the opening (existing on the optical path described above) 24c, 24d, 24e, 24f) are switched. The color filter turret plate 24 corrects the sensitivity of the wavelength set as appropriate and advances the measurement light that has passed through the third lens 23 to the neutral density filter 25.

  The neutral density filter 25 adjusts the intensity of the measurement light that has passed through the color filter turret plate 24. The neutral density filter 25 includes a plate-like filter member 25a and a drive unit 25b having an output shaft connected to an end thereof. The filter member 25a has a predetermined light attenuation rate. The drive unit 25b allows the filter member 25a to be inserted into and removed from the optical path (measurement optical path) from the third lens 23 toward the neutral density filter 25, and is configured by a pulse motor in this embodiment. For this reason, the neutral density filter 25 can switch between reducing the intensity and allowing the measurement light that has passed through the color filter turret plate 24 to pass through without changing the intensity. In the neutral density filter 25, when the drive unit 25b is appropriately driven under the control of the arithmetic control unit 31 described later, the filter member 25a is put in and out of the above-described optical path. The neutral density filter 25 causes the measurement light that has passed through the color filter turret plate 24 to travel to the fourth lens 26 by appropriately adjusting the intensity.

  As described above, the fourth lens 26 constitutes a relay lens in cooperation with the third lens 23, and relays the image of the measurement object to the light receiving unit 12 (its light receiving surface). In the photometric optical system 15, the measurement light appropriately adjusted by the color filter turret plate 24 and the neutral density filter 25 travels to the neutral density filter turret plate 27.

  The neutral density filter turret plate 27 adjusts the intensity of the measurement light that has passed through the fourth lens 26 in a stepwise manner. The neutral density filter turret plate 27 includes a disk member 27a and a drive unit 27b having an output shaft coupled to the central axis thereof. In the disk member 27a, a plurality of openings (four in the example shown in FIG. 3) are provided around the central axis, and the four openings 27c, 27d, 27e, and 27f have different transmittances (dimming magnifications). A filter is provided. The drive part 27b adjusts the rotation posture of the disk member 27a, and is constituted by a pulse motor in this embodiment. This dimming filter turret plate 27 is on an optical path (measurement optical path) from one of the openings (27c, 27d, 27e, 27f) toward the light receiving unit 12 through the opening (27c, 27d, 27e, 27f) depending on the rotational posture of the disk member 27a. It is possible to exist in a position. For this reason, the neutral density filter turret plate 27 can adjust the intensity of the measurement light that has passed through the fourth lens 26 in a stepwise manner. The neutral density filter turret plate 27 is adjusted by adjusting the rotational posture of the disk member 27a by appropriately driving the drive unit 27b under the control of the arithmetic control unit 31 to be described later, that is, the opening existing on the optical path described above. (27c, 27d, 27e, 27f) are switched. The neutral density filter turret plate 27 adjusts the measurement light that has passed through the fourth lens 26 to an appropriately set intensity and advances the measurement light to the light receiving unit 12. For this reason, the photometric optical system 15 can guide the measurement light emitted from the measurement object to the light receiving unit 12 while appropriately adjusting the measurement light.

  The light receiving unit 12 outputs a signal that is an analog value having a magnitude (intensity) corresponding to the amount of light received by the light receiving surface. In this embodiment, the light receiving unit 12 is a photomultiplier tube (so-called photomultiplier) which is a high-sensitivity photodetector having a current amplification (electron multiplication) function from the viewpoint of enabling detection of a crosstalk value to be described later. Is used. The light receiving unit 12 receives the measurement light guided by the photometric optical system 15 (optical system 11), and supplies a current (analog signal) having a magnitude (intensity) corresponding to the light amount to the circuit unit 13 (the CCD analog PCB 38). Output to.

  The circuit unit 13 calculates colorimetric values (luminance, chromaticity, color temperature) in the measurement light based on the analog signal output from the light receiving unit 12. The circuit unit 13 includes an arithmetic control unit 31, an AC adapter 32, a DC-DC power source 33, an LCD (Liquid Crystal Display) display 34, an operation key 35, an external input / output terminal 36, a first A / D converter 37, and a CCD ( It has a Charge Coupled Device) analog PCB (CCD analog printed circuit board) 38.

  The calculation control unit 31 drives the LCD display 34, drive processing based on an operation performed on the operation key 35, calculation processing of a colorimetric value based on a signal from the light receiving unit 12, and a photometric optical system 15 (color Control of the driving of the filter turret plate 24, the neutral density filter 25 and the neutral density filter turret plate 27), and data transmission / reception processing with an external device (see reference numeral 41 in FIG. 1) via the external input / output terminal 36 will be described later. This is centralized by the program stored in the storage unit 40. In this embodiment, the arithmetic control unit 31 is constituted by a central processing unit (CPU (Central Processing Unit)) in which ROM and RAM are built in one chip. The arithmetic control unit 31 includes a second A / D converter 39 and a storage unit 40.

  The second A / D converter 39 converts an analog signal output from the CCD analog PCB 38 (light receiving unit 12) into a digital signal, as will be described later. The second A / D converter 39 has a processing speed capable of converting an analog signal output from the CCD analog PCB 38 (light receiving unit 12) into a digital signal at high speed. Here, the processing speed that can be converted into a digital signal at high speed enables the storage of waveform information (a mode of change in intensity with respect to time) in an analog signal output from the CCD analog PCB 38 (light receiving unit 12). This means that conversion processing can be performed at time intervals. That is, in the converted digital signal, the conversion process can be performed at a short time interval that enables waveform information (a mode of change in intensity with respect to time) to be read (a sufficient number of samplings for the time Can be ensured). In the present embodiment, the second A / D converter 39 constitutes a part of the calculation control unit 31, that is, is provided in the calculation control unit 31. Further, the second A / D converter 39 has a resolution of 10 bits in this embodiment. Further, in the present embodiment, the second A / D converter 39 is capable of analog-to-digital conversion of an analog signal output from the CCD analog PCB 38 (light receiving unit 12) every 11 [μsec], as will be described later. It is supposed to have speed.

  When a digital signal is input from the second A / D converter 39 or the first A / D converter 37, the arithmetic control unit 31 appropriately performs calorimetric value calculation processing using the digital signal. The colorimetric value calculation process appropriately calculates the luminance, chromaticity, color temperature and the like in the measurement light. In the present invention, a crosstalk value described later can be calculated as the colorimetric value. The generation of the crosstalk value will be described later in detail. In addition, when performing the calorimetric value generation process, the arithmetic control unit 31 appropriately stores data and the like in the generation process in the storage unit 40 and appropriately reads the data stored in the storage unit 40 from the storage unit 40.

  In the arithmetic control unit 31, power is supplied via the AC adapter 32 and the DC-DC power source 33. The LCD display 34 is driven under the control of the arithmetic control unit 31 to display the generated photometric characteristics (crosstalk value and the like described later), other commands, and the like. The operation keys 35 are provided to perform selection operations for various functions and input operations for various functions in the photometric device 10. A signal based on the operation performed on the operation key 35 is output to the arithmetic control unit 31. The operation key 35 may be provided independently of the LCD display 34. The operation key 35 is a screen displayed on the LCD display 34 by mounting a touch panel function on the LCD display 34. It may be configured.

  Although not shown, the external input / output terminal 36 can be connected to an external input / output terminal, and the external input / output terminal 41 (the control unit (see FIG. 1)), the arithmetic control unit 31, The information (generated colorimetric values, analog signals output from the CCD analog PCB 38 (light receiving unit 12), etc.) can be exchanged. In this embodiment, the external input / output terminal 36 includes a LAN interface that enables connection with a device having a LAN function, an RS-232C interface that enables connection with a serial communication port of the RS-232C, Is used.

  The first A / D converter 37 converts the analog signal output from the CCD analog PCB 38 (light receiving unit 12) into a digital signal and outputs the digital signal to the arithmetic control unit 31. It is assumed that the first A / D converter 37 has a resolution larger than at least the second A / D converter 39. More preferably, the first A / D converter 37 uses a luminance meter in a digital signal obtained by converting an analog signal having a magnitude (intensity) corresponding to the amount of light received by the light receiving unit 12 output via a CCD analog PCB 38 described later. It has a resolution capable of satisfying the accuracy required. In the present embodiment, the first A / D converter 37 is provided outside the arithmetic control unit 31 and has a resolution of 16 bits.

  The CCD analog PCB 38 generates a current (analog signal) having a magnitude (intensity) corresponding to the amount of received light output from the light receiving unit 12 and a voltage (analog signal) having a magnitude (intensity) corresponding to the amount of received light at the light receiving unit 12. ). The CCD analog PCB 38 can output the analog signal to the first A / D converter 37 and to the arithmetic control unit 31 (including the second A / D converter 39).

  Thereby, in the photometry device 10, as shown in FIG. 1, the measurement light is measured by making the objective lens 16 of the optical system 11 face the arbitrary measurement object (stereoscopic image system 50). Is received by the light receiving unit 12 and a signal (analog signal) based on the received light is output to the circuit unit 13, whereby a colorimetric value (luminance, chromaticity, color temperature) in the measurement light can be generated.

  The photometric device 10 can further measure the crosstalk value in the stereoscopic image system 50. That is, the arithmetic control unit 31 can perform arithmetic processing for measuring the crosstalk value in the stereoscopic image system 50. First, crosstalk will be described. In the stereoscopic image system 50, since crosstalk can occur even in a scene where an image corresponding to either the left or right eye is acquired, in the following description, a scene where a right-eye image is acquired will be described. It will be described and omitted for the left eye.

  As described above, the stereoscopic image system 50 (see FIG. 1) uses the stereoscopic glasses 52 that are driven in synchronization with the display of the right-eye image and the left-eye image on the stereoscopic display 51. Thus, only one image corresponding to the eye is acquired in one eye (see FIG. 2). At this time, when viewing the stereoscopic display 51 via the right-eye lens portion 52a of the stereoscopic glasses 52, the display signal corresponding to the right-eye image among the display signals output from the stereoscopic display 51. It is desirable to acquire only (refer FIG.2 (b)). However, in reality, when the stereoscopic display 51 is viewed through the right-eye lens portion 52a of the stereoscopic glasses 52, the luminance is very weak in the time zone in which the image corresponding to the left eye is output. The value is detected (see the two-dot chain line in FIG. 2B). This is because a part of the display signal corresponding to the left eye is input even when the stereoscopic display 51 is viewed through the lens unit 52a on the right eye side of the stereoscopic glasses 52 due to some cause in the stereoscopic image system 50. That is, it is considered that a part of the display signal corresponding to the left eye is mixed (leaked) in the display signal corresponding to the right eye. In this way, when viewing the stereoscopic display 51 through the lens portion 52a on the one eye side of the stereoscopic glasses 52, it is indicated that a part of the display signal corresponding to the other eye is mixed. In the specification, it is said that crosstalk occurs, and the intensity (luminance value in this embodiment) of mixed crosstalk (display signal corresponding to the other eye) is referred to as a crosstalk value.

  In the stereoscopic image system 50 (stereoscopic display 51), if crosstalk occurs, image degradation (particularly, deterioration of color reproducibility) is caused. Therefore, it is desired to suppress the occurrence of crosstalk. It is rare. For this purpose, it is necessary to measure the crosstalk (crosstalk value) with high accuracy.

  Next, measuring the crosstalk value in the stereoscopic image system 50 using the photometric device 10 will be described with reference to FIG. FIG. 4 is a flowchart showing the measurement processing content of the crosstalk value (colorimetric value) executed by the arithmetic control unit 31 (program stored in the storage unit 40). Hereinafter, each step of the flowchart of FIG. 4 will be described. The measurement of the crosstalk value is started when the operation key 35 is operated to execute the measurement of the crosstalk value. In the measurement of the crosstalk value, as shown in FIG. 1, the photometric device 10 is installed in front of the stereoscopic display 51, and the measurement light is input to the input portion (the objective lens 16 (see FIG. 3)). A lens portion 52 a on the right eye side of the viewing glasses 52 is arranged. Then, the stereoscopic display 51 and the stereoscopic glasses 52 are driven in synchronization with each other, and an inspection image (left and right display signals (see FIG. 2A)) is output to the stereoscopic display 51. Let For this reason, in the photometric device 10, the display signal (see FIG. 2B) output from the stereoscopic display 51 and passed through the right eye side lens portion 52a of the stereoscopic glasses 52 is acquired (received light). )can do.

  In step S1, an analog signal from the light receiving unit 12 corresponding to the received measurement light is acquired as a digital signal from the first A / D converter 37, and the process proceeds to step S2. In this step S1, an analog signal having a magnitude (intensity) corresponding to the amount of light received by the light receiving unit 12 output via the CCD analog PCB 38 is acquired by the first A / D converter 37. . Step S1 continues for the first predetermined time T1. The first predetermined time T1 is appropriately set in consideration of the resolution and processing speed in the first A / D converter 37 from the viewpoint of satisfying the accuracy set as the luminance meter. The first predetermined time T1 is set to 100 [msec] in this embodiment. The accuracy set as the luminance meter is the accuracy guaranteed in the photometric device 10, and is set as appropriate.

  In step S2, following the acquisition of the digital signal from the first A / D converter 37 in step S1, the luminance value of the measurement light at the first predetermined time T1 is calculated based on the digital signal, and the process proceeds to step S3. . In this step S2, the amount of light received by the light receiving unit 12 at the first predetermined time T1 is converted into a luminance value on the basis of the digital signal acquired via the first A / D converter 37, thereby providing stereoscopic glasses 52. The reference luminance value (reference colorimetric value) of the display signal from the stereoscopic display 51 acquired through the right-eye lens unit 52a is calculated. The converted luminance value is a photometric amount obtained by evaluating the intensity of light emitted toward the observer with the sensitivity of the human eye. This reference luminance value is based on a digital signal from the first A / D converter 37 having a resolution of 16 bits, and the first predetermined time T1 (100 [msec] in this embodiment) is used as the measurement time. For this reason, the accuracy set as a luminance meter is sufficiently satisfied. Therefore, the digital signal generated (converted) by the first A / D converter 37 based on the analog signal output from the light receiving unit 12 (CCD analog PCB 38) is the reference colorimetry at the first predetermined time T1 in the measurement light. It becomes value data.

  In step S3, following the calculation of the reference luminance value in step S2, an analog signal from the light receiving unit 12 corresponding to the received measurement light is acquired as a digital signal via the second A / D converter 39, and step S4. Proceed to In step S3, an analog signal having a magnitude (intensity) corresponding to the amount of light received by the light receiving section 12 output via the CCD analog PCB 38 is converted by the second A / D converter 39 (see FIG. 6). ), Get. Step S3 continues for the second predetermined time T2. A method for setting the second predetermined time T2 will be described later. In this embodiment, based on the fact that the second A / D converter 39 can perform analog-digital conversion every 11 [μsec], the second predetermined time T2 is set to 22 so that the conversion can be performed 2000 times. [Msec] is set. In the digital signal acquired in step S3, since the second A / D converter 39 has a high processing speed as described above, it is possible to read the waveform information indicating how the intensity changes with time. Yes. Therefore, the digital signal generated (converted) by the second A / D converter 39 based on the analog signal output from the light receiving unit 12 (CCD analog PCB 38) is the waveform data at the second predetermined time T2 in the measurement light. Become.

  In step S4, following the acquisition of the digital signal from the second A / D converter 39 in step S3, a small maximum with respect to a large maximum value in the measurement light based on the digital signal (waveform data at the second predetermined time T2). The ratio of values is calculated, and the process proceeds to step S5. In this step S4, a large maximum value, that is, a peak value in the display signal corresponding to the right eye (Pl in FIG. 6) is obtained from the waveform information indicating the change in intensity with respect to time in the digital signal obtained via the second A / D converter 39. Reference) is extracted, and an average value thereof is calculated. Further, from the waveform information indicating the change in intensity with respect to time in the digital signal acquired via the second A / D converter 39, a small maximum value, that is, a peak value in the crosstalk (display signal corresponding to the left eye) (in FIG. 6). Ps) is extracted, and an average value thereof is calculated. Thereafter, the ratio of the small maximum value to the large maximum value in the digital signal acquired via the second A / D converter 39 is calculated based on the average value of the large maximum value and the average value of the small maximum value. In step S4, only the ratio of the small maximum value to the large maximum value at the second predetermined time T2 in the measurement light is obtained, and the luminance value (colorimetric value) based on the digital signal from the second A / D converter 39 is obtained. ) Is not calculated.

  In step S5, following the calculation of the ratio of the small maximum value to the large maximum value in step S4, the crosstalk value is calculated, and the crosstalk value measurement process is terminated. In step S5, the crosstalk value is calculated by multiplying the reference luminance value calculated in step S2 by the ratio of the small maximum value to the large maximum value calculated in step S4 (crosstalk value = reference luminance value × (Small maximum / large maximum)).

  In the photometric device 10, when the user selects to execute the crosstalk value measurement with the operation key 35, the process proceeds to step S1, step S2, step S3, step S4, step S5 in the flowchart of FIG. Thus, the crosstalk value can be calculated. The calculated (measured) crosstalk value is displayed on the LCD display 34 under the control of the arithmetic control unit 31. Therefore, in the photometric device 10, the flowchart of FIG. 4 is a cross-section for calculating the crosstalk value in cooperation with the light receiving unit 12 (CCD analog PCB 38), the first A / D converter 37 and the second A / D converter 39. It functions as a talk value calculation means. Further, the first A / D converter 37 functions as a first processing unit that generates reference colorimetric value data at the first predetermined time T1 based on the analog signal from the light receiving unit 12 that has received the measurement light. Further, the second A / D converter 39 functions as a second processing unit that generates waveform data at the second predetermined time T2 based on the analog signal from the light receiving unit 12 that has received the measurement light.

  In the photometric device 10, when the crosstalk value is measured, when the external device 41 is connected to the external input / output terminal 36 as shown in FIG. 1, the arithmetic control unit 31 sets the CCD analog PCB 38. An analog signal having a magnitude (intensity) corresponding to the amount of light received by the light receiving unit 12 is output from the external input / output terminal 36 to the external device 41. At this time, in this embodiment, the arithmetic control unit 31 measures the time range used for the measurement of the crosstalk value in the analog signal, that is, the time range that is the basis for the calculation for quantification as the crosstalk value. The range signal Sm (see FIG. 5) is output from the external input / output terminal 36 to the external device 41. The calculation control unit 31 outputs a voltage having a predetermined magnitude (5 [V] in the example of FIG. 5) during the corresponding time range as the measurement range signal Sm. This time range is from the time when the calculation control unit 31 in step S3 starts acquiring the digital signal from the second A / D converter 39 according to the measurement light (the time when the counting of the second predetermined time T2 is started). This is until the time when the calculation control unit 31 in step S3 ends the acquisition of the digital signal from the second A / D converter 39 according to the measurement light (when the second predetermined time T2 has elapsed) (see FIG. 5).

  Next, a method for setting the second predetermined time T2 will be described. The second predetermined time T2 is an analog signal having a magnitude (intensity) corresponding to the amount of light received by the light receiving unit 12 output via the CCD analog PCB 38, that is, a digital signal converted by the second A / D converter 39. The signal is set according to the lighting frequency (output characteristic) set by the stereoscopic display 51 (stereoscopic image system 50) so that at least four waveforms exist. In other words, the second predetermined time T2 is set to two cycles or more in which the output of the pair of display signals for the stereoscopic image on the stereoscopic display 51 is performed twice. Accordingly, in step S4 of the flowchart of FIG. 4 described above, two or more large maximum values, that is, two or more peak values (see reference numeral Pl in FIG. 6) in the display signal corresponding to the right eye can be extracted, and a small maximum value, Since two or more peak values (see symbol Ps in FIG. 6) in the crosstalk (display signal corresponding to the left eye) can be extracted, the ratio of the small maximum value to the large maximum value in the measurement light can be obtained more accurately. be able to.

  In particular, in this embodiment, the second predetermined time T2 is an analog signal having a magnitude (intensity) corresponding to the amount of light received by the light receiving unit 12 output via the CCD analog PCB 38, that is, the second A / D converter. The digital signal converted by 39 is set according to the lighting frequency set by the stereoscopic display 51 (stereoscopic image system 50) so that at least six waveforms exist. This will be described below with reference to FIG. 6 and set values in the present embodiment.

  In the present embodiment, as described above, since the lighting frequency of the stereoscopic display 51 (stereoscopic image system 50) is set to 120 [Hz], as shown in FIG. A pair of display signals is output at a pace of about 8.3 [msec]. On the other hand, in the photometric device 10 (the operation control unit 31), the second predetermined time T2 is set to 22 [msec] from the viewpoint of allowing at least six waveforms to exist. Then, at least six waveforms are present during the second predetermined time T2 (22 [msec]) in the display signal repeatedly output from the stereoscopic display 51 regardless of the start time of the second predetermined time T2. be able to. That is, at least three large waveforms (display signals corresponding to the right eye) and three small waveforms (display signals corresponding to the right eye) in the display signal repeatedly output from the stereoscopic display 51 regardless of the start time of the second predetermined time T2. Crosstalk (display signal corresponding to the left eye)).

  However, the start point of the second predetermined time T2 (22 [msec]) is the output of the display signal for displaying the right-eye image on the stereoscopic display 51 or the display signal for displaying the left-eye image. If it does not coincide with any of the time points when the output is started (the time point when the left and right eye images are switched), the first or last waveform information of the waveform information acquired within the second predetermined time T2 is included in the waveform information. A scene that does not include a peak value may occur (in the example of FIG. 6, the waveform at the left end). Therefore, in the present embodiment, the arithmetic control unit 31 extracts the first waveform information and the last waveform information viewed on the time axis from the waveform information in the digital signal acquired through the second A / D converter 39. A large maximum value, that is, a peak value in the display signal corresponding to the right eye (see two signs Pl in the intermediate position) is extracted from the remaining waveform information, and a small maximum value, that is, crosstalk (a display corresponding to the left eye) is extracted. Signal) is extracted (see the two symbols Ps at the intermediate position). Thereby, even if the second predetermined time T2 is started without being synchronized with the stereoscopic display 51 (stereoscopic image system 50), two or more large maximum values, that is, the peak value Pl in the display signal corresponding to the right eye are extracted. Since two or more peak values Ps in the small maximum value, that is, the crosstalk (display signal corresponding to the left eye) can be extracted, the ratio of the small maximum value to the large maximum value in the measurement light can be further increased. It can be determined accurately.

  The first predetermined time T1 and the second predetermined time T2 described above are stored (registered) in the storage unit 40 in advance, and the storage (registration) is due to an operation performed on the operation key 35. Alternatively, it may be obtained from another device connected via the external input / output terminal 36.

  As described above, in the photometric device 10 according to the present embodiment, the first A having a high resolution with respect to an analog signal having a magnitude (intensity) corresponding to the amount of light received by the light receiving unit 12 output via the CCD analog PCB 38. A reference luminance value (reference colorimetric value) is calculated based on a digital signal (reference colorimetric value data) generated by the / D converter 37, and a digital signal generated by the second A / D converter 39 having a high processing speed The crosstalk value is calculated by calculating the ratio of the small maximum value to the large maximum value based on (waveform data) and multiplying the reference luminance value by the ratio of the small maximum value to the large maximum value. Thus, an accurate crosstalk value can be obtained. In other words, the photometric device 10 converts the absolute value (reference luminance value (reference luminance value (reference luminance value)) based on a digital signal (reference colorimetric value data) obtained through the first A / D converter 37 having high resolution. Colorimetric value)) and a relative relationship in luminance value based on a digital signal (waveform data) obtained through the second A / D converter 39 having a high processing speed (relative to the display signal originally required) The ratio of the crosstalk value) is calculated, and the crosstalk value is calculated from the relative relationship using the absolute value as a reference, so that an accurate crosstalk value can be obtained.

  In the photometric device 10, a digital signal (second predetermined time T2) set according to the lighting frequency set in the stereoscopic display 51 (stereoscopic image system 50) so that at least four waveforms exist. On the basis of the waveform data), the ratio of the small maximum value to the large maximum value in the display signal from the stereoscopic display 51 through the stereoscopic glasses 52 is calculated. Two or more peak values in the signal) and two or more peak values in the small maximum value (crosstalk) can be extracted, so that the small maximum value for the display signal (measurement light) is small. The ratio of local maximum values can be obtained more accurately. For this reason, a crosstalk value can be obtained more accurately.

  Further, the photometric device 10 sets the second predetermined time T2 according to the lighting frequency set in the stereoscopic display 51 (stereoscopic image system 50) so that at least six waveforms exist, and the second predetermined time T2 is set. Of the waveform information in the digital signal at time T2, the first waveform information and the last waveform information viewed on the time axis are excluded from the extraction target, and the large maximum value in the display signal from the stereoscopic display 51 is obtained. Therefore, even if the second predetermined time T2 is started without being synchronized with the stereoscopic display 51 (stereoscopic image system 50), a large maximum value (necessary display signal) is calculated. Since two or more peak values can be extracted and two or more peak values at a small maximum value (crosstalk) can be extracted. It can be determined the ratio of the small maximum values for a large maximum value of the signal (the measurement light) more accurately. For this reason, a crosstalk value can be obtained more accurately without synchronization (without providing a mechanism therefor).

  In the photometric device 10, since the second A / D converter 39 is provided in the calculation control unit 31, analog-digital conversion in the second A / D converter 39 can be performed at a higher speed. Based on the digital signal (waveform data) at the predetermined time T2, the ratio of the small maximum value to the large maximum value in the measurement light can be obtained more accurately. For this reason, a crosstalk value can be obtained more accurately.

  In the photometric device 10, when the crosstalk value is measured, the external device 41 is connected to the external input / output terminal 36, so that the magnitude corresponding to the amount of light received by the light receiving unit 12 output via the CCD analog PCB 38. The analog signal of the intensity (intensity) can be output to the external device 41. For this reason, the user can analyze the analog signal including the generated crosstalk together with the crosstalk value as the measurement value by the photometric device 10.

  When the photometric device 10 outputs an analog signal having a magnitude (intensity) corresponding to the amount of light received by the light receiving unit 12 output via the CCD analog PCB 38 from the external input / output terminal 36 to the external device 41, A measurement range signal Sm indicating the time range used for measuring the talk value can also be output. Therefore, the user can easily grasp the correlation between the crosstalk value as the measurement value by the photometric device 10 and the analog signal.

  In the photometric device 10, since the first A / D converter 37 is provided outside the arithmetic control unit 31, the second A / D converter (having a processing speed that can be converted into a digital signal at high speed). ), The first A / D converter having higher resolution than the second A / D converter is provided, and the arithmetic processing method (program for that) in the arithmetic control unit is as described above. It can be applied to an existing photometric device simply by changing to.

  Therefore, the photometric device 10 according to the present invention can accurately measure the crosstalk value.

  In the above-described embodiment, an example of the photometric device according to the present invention has been described. However, a colorimetric value is calculated based on a light receiving unit that receives light from a symmetrical object and a light amount acquired by the light receiving unit. An arithmetic control unit, a first processing unit that generates reference colorimetric value data at a first predetermined time based on a signal from the light receiving unit according to the acquired light amount, and a signal from the light receiving unit according to the acquired light amount A second processing unit for generating waveform data at a second predetermined time based on the second processing unit, wherein the arithmetic control unit calculates a ratio of a small maximum value to a large maximum value in the waveform data from the second processing unit. Any photometric device that calculates and calculates the colorimetric value by multiplying the ratio of the calculated small maximum value to the reference colorimetric value based on the colorimetric value data from the first processing unit, Limited to the above examples Not to.

  In the above-described embodiment, an example of the program according to the present invention (that realizes the control process in the flowchart of FIG. 4) has been described. However, the light receiving unit that receives light from the measurement object and the light receiving unit A calculation control unit that calculates a colorimetric value based on the amount of light acquired by the unit, and a first process that generates reference colorimetric value data at a first predetermined time based on a signal from the light receiving unit corresponding to the acquired amount of light And a second processing unit that generates waveform data at a second predetermined time based on a signal from the light receiving unit according to the acquired light amount, the arithmetic control unit of the photometric device includes the second processing unit A function of calculating a ratio of a small maximum value to a large maximum value in the waveform data from, and a ratio of the calculated small maximum value to a reference colorimetric value based on the colorimetric value data from the first processing unit. Multiply A function of calculating the colorimetric value by may be a program for actualizing, but is not limited to the aforementioned embodiments.

  Further, in the above-described embodiment, the crosstalk value converted into the luminance value is calculated as the colorimetric value. However, the colorimetric value indicating the intensity of the mixed crosstalk (display signal corresponding to the other eye) may be used. For example, chromaticity may be used, and is not limited to the above-described embodiment.

  In the above embodiment, the calculation control unit 31 calculates the reference luminance value (reference colorimetric value) of the display signal from the stereoscopic display 51 acquired through the stereoscopic glasses 52. If the reference luminance value (reference colorimetric value) is calculated based on the reference colorimetric value data (digital signal converted by the first A / D converter 37) generated by the / D converter 37, the first A / D The D converter 37 may calculate a reference luminance value (reference colorimetric value), and is not limited to the above-described embodiment. When the first A / D converter 37 calculates the reference luminance value (reference colorimetric value), for example, the first A / D converter 37 may be provided with an arithmetic control unit for the calculation. An arithmetic circuit may be added to the 1 A / D converter 37 for the calculation.

  In the above-described embodiment, the first A / D converter 37 has a resolution of 16 bits. However, the first A / D converter 37 may have at least a resolution larger than that of the second A / D converter 39, and is limited to the above-described embodiment. Is not to be done.

  In the above-described embodiment, the second A / D converter 39 is provided in the calculation control unit 31. However, the analog signal output from the CCD analog PCB 38 (light receiving unit 12) is converted into a digital signal at high speed. However, the present invention is not limited to the above-described embodiments.

  In the above-described embodiment, the second A / D converter 39 has a resolution of 10 bits. However, the analog signal output from the CCD analog PCB 38 (light receiving unit 12) can be converted into a digital signal at high speed. Any device having a processing speed may be used, and the present invention is not limited to the above-described embodiments.

  In the above-described embodiment, the second A / D converter 39 has a processing speed capable of performing analog-digital conversion every 11 [μsec], but is output from the CCD analog PCB 38 (light receiving unit 12). As long as conversion processing can be performed at a time interval that enables storage of waveform information indicating a manner of change in intensity with respect to time in an analog signal, it is not limited to the above-described embodiment.

  As described above, the photometric device and the program of the present invention have been described based on the embodiments. However, the specific configuration is not limited to this embodiment, and design changes and additions are possible without departing from the gist of the present invention. Etc. are allowed.

DESCRIPTION OF SYMBOLS 10 Photometry apparatus 12 Light-receiving part 31 Operation control part 37 1st A / D converter (1st process part)
39 Second A / D Converter (Second Processing Unit)
50 Stereoscopic image system (as a measurement object) Pl Peak value at a large maximum value Ps Peak value at a small maximum value Sm Measurement range signal T1 First predetermined time T2 Second predetermined time

Claims (7)

A light receiving unit for receiving light from a symmetrical object;
An arithmetic control unit that calculates a colorimetric value based on the amount of light acquired by the light receiving unit;
A first processing unit that generates reference colorimetric value data at a first predetermined time based on a signal from the light receiving unit corresponding to the acquired light amount;
A second processing unit that generates waveform data at a second predetermined time based on a signal from the light receiving unit corresponding to the acquired light amount;
The arithmetic control unit calculates a ratio of a small maximum value to a large maximum value in the waveform data from the second processing unit, and calculates a reference colorimetric value based on the colorimetric value data from the first processing unit. The photometric device characterized in that the colorimetric value is calculated by multiplying the calculated ratio of the small maximum values. The light receiving unit outputs an analog signal having a magnitude corresponding to the amount of received light,
The second processing unit includes a second analog-to-digital conversion unit having a processing speed for storing waveform information in the analog signal from the light receiving unit,
The first processing unit includes a first analog-digital conversion unit having a higher resolution with respect to the magnitude of an analog signal from the light receiving unit than the second analog-digital conversion unit. The photometric device according to 1.   The photometric device according to claim 2, wherein the second analog-digital conversion unit is built in the arithmetic control unit.   4. The photometric device according to claim 2, wherein the first analog-digital conversion unit is provided separately from the arithmetic control unit. 5.   The second predetermined time is set according to an output characteristic of the measurement symmetrical object so as to be able to generate the waveform data including at least two of the large maximum values and at least two of the small maximum values. The photometric device according to any one of claims 1 to 4, wherein the photometric device is provided.   6. The method according to claim 1, wherein the calculation control unit generates a measurement range signal indicating a period from a start time of the second predetermined time to an end time of the second predetermined time. The photometric device according to item. A light receiving unit that receives light from a symmetrical object, a calculation control unit that calculates a colorimetric value based on the amount of light acquired by the light receiving unit, and a first signal based on a signal from the light receiving unit that corresponds to the acquired amount of light. A first processing unit that generates reference colorimetric value data at a predetermined time; and a second processing unit that generates waveform data at a second predetermined time based on a signal from the light receiving unit corresponding to the acquired light amount. In the arithmetic control unit of the photometric device provided,
A function of calculating a ratio of a small maximum value to a large maximum value in the waveform data from the second processing unit;
A function of calculating the colorimetric value by multiplying a reference colorimetric value based on the colorimetric value data from the first processing unit by the ratio of the calculated small maximum value;
A program characterized by realizing.