Optical measurement device, optical measurement system, and gamma adjustment method

Abstract

Provided is a light measurement device, a light measurement system, and a gamma adjustment method that shorten a measurement time. The light measurement device measures a light emission characteristic of an object, and includes: a light emission condition acquisition section that acquires a light emission condition of the object from the outside in advance; and a measurement condition setting section that sets a measurement condition based on the acquired light emission condition.

Description

Technical Field

[0001] This disclosure relates to an optical measurement device, an optical measurement system, and a gamma adjustment method. Background Technology

[0002] The gamma value of a display can be measured by measuring its brightness when it emits light. A gamma adjustment technique is known that measures the gamma value during the display inspection process and adjusts it to a desired gamma value (Patent Document 1).

[0003] As a light measurement device for measuring the brightness, chromaticity, etc., of a display when it emits light, a color analyzer with multiple measurement ranges is known. This color analyzer distinguishes between multiple measurement ranges based on the brightness of the display when it emits light, thereby enabling the measurement of the display's brightness under optimal conditions.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2009-244566 Summary of the Invention

[0007] In recent years, with the continuous improvement of display performance, the conditions for gamma adjustment have become increasingly complex. Consequently, the brightness measurement conditions in color analyzers have also become increasingly complex, with low-brightness and high-brightness measurements being performed repeatedly. Since the optimal measurement conditions for low-brightness and high-brightness measurements differ, it is necessary to perform virtual measurements to derive the optimal conditions, which consumes a significant amount of time. This is especially true for low-brightness measurements, where the measurement itself takes time, and virtual measurements consume even more. As a result, the time spent on gamma adjustment is constantly increasing.

[0008] The problem to be solved by this disclosure is to provide an optical measurement device, an optical measurement system, and a gamma adjustment method that shortens the measurement time.

[0009] Methods for solving problems

[0010] To address the aforementioned issues, the optical measuring device disclosed herein is an optical measuring device for measuring the luminescence characteristics of a test subject, comprising: The luminescence condition acquisition unit acquires the luminescence conditions of the subject from the outside in advance; and The measurement condition setting unit sets the measurement conditions based on the acquired emission conditions.

[0011] Claim 2 is in claim 1, The luminescence conditions include those related to the target brightness.

[0012] Claim 3 is in claim 2, The luminescence conditions include conditions related to the time required from the start of luminescence by the subject until the subject emits luminescence at the target brightness.

[0013] Claim 4 is in claim 1, The luminescence conditions include conditions related to the driving frequency of the subject.

[0014] Claim 5 is in claim 1, The emission conditions include at least one of the following: conditions related to the number of frames displayed on the subject within one second and conditions related to the emission display color.

[0015] Claim 6 is in claim 1, The measurement conditions include conditions related to the tolerance range and category of the measured values.

[0016] Claim 7 is in claim 1, The measurement conditions include those related to the total exposure time.

[0017] Claim 8 is in claim 2, The measurement conditions include those related to the measurement range set based on the target brightness.

[0018] Claim 9 is in claim 1, It has a storage unit that stores measurement history, linking past measurement results with measurement conditions. The optical measurement device sets the measurement conditions based on the emission conditions and the measurement history.

[0019] Claim 10 is in claim 1, It has an optical attenuation filter. The measurement conditions include those related to the insertion and removal of the optical attenuation filter.

[0020] Claim 11 is in claim 1, It has an optical attenuation filter. During the period from when the subject begins to emit light until the subject emits light at the target brightness or chromaticity, at least a portion of the insertion and removal of the light attenuation filter is performed.

[0021] The optical measurement system of this disclosure as described in claim 12 is an optical measurement system for measuring the luminescence characteristics of a test subject. have: The luminescence condition setting unit sets the luminescence conditions of the subject; The measurement condition setting unit sets measurement conditions based on the emission conditions; and The measurement unit performs measurements based on the aforementioned measurement conditions.

[0022] Claim 13 is in claim 12, The object being examined is a monitor.

[0023] Claim 14 is in claim 13, The brightness is measured at the gamma adjustment point of the subject and the gamma value is calculated.

[0024] The gamma adjustment method of this disclosure as described in claim 15 has the following characteristics: The step of acquiring the gamma value of the display using the optical measurement system of claim 14; and The process of correcting the gamma value of the display.

[0025] According to this disclosure, the time required for optical measurement can be shortened. Attached Figure Description

[0026] Figure 1 This is a block diagram illustrating an example of the configuration of a light measurement system.

[0027] Figure 2 This is a block diagram illustrating an example of the configuration of a tristimulus value direct-reading optical measurement device.

[0028] Figure 3 This is a flowchart illustrating an example of the operation of a light measuring device.

[0029] Figure 4 This is a flowchart illustrating an example of a process in the gamma adjustment method.

[0030] Figure 5 This is a flowchart illustrating an example of the action taken to determine whether the measurement results of luminance or chromaticity in the measurement of gamma value meet a predetermined value.

[0031] Figure 6 This is a sequence diagram illustrating an example of the operation of an optical measurement system in gamma measurement.

[0032] Figure 7 This is a flowchart illustrating an example of the operation of the second control unit (11) in the setting of measurement conditions.

[0033] Figure 8 This is a sequence diagram illustrating a variation of the operation of an optical measurement system in gamma measurement, as shown in Example 1.

[0034] Figure 9 This is a sequence diagram illustrating a variation of the operation of an optical measurement system in gamma measurement, as shown in Example 2.

[0035] Figure 10 This is a sequence diagram illustrating a variation of the operation of an optical measurement system in gamma measurement, example 3. Detailed Implementation

[0036] Hereinafter, one or more embodiments of the present disclosure will be described with reference to the accompanying drawings. However, the scope of the present disclosure is not limited to the disclosed embodiments.

[0037] [Composition of the optical measurement system]

[0038] Figure 1 This is a block diagram illustrating an example of the configuration of the optical measurement system 100 according to this embodiment. The optical measurement system 100 includes an optical measurement device 10 and a management device 30. Furthermore, in the optical measurement system 100, the optical measurement device 10 and the management device 30 may be an integrated device.

[0039] [Composition of the optical measurement device]

[0040] The optical measuring device 10 of this embodiment is used to measure the luminescence characteristics of the test subject 1. Preferably, the optical measuring device 10 measures the brightness or chromaticity of the test subject 1 when it emits light.

[0041] Figure 2 This is a block diagram illustrating an example of the configuration of the tristimulus value direct-reading type optical measurement device 10 according to this embodiment. Note that the optical measurement device of this embodiment is not limited to the tristimulus value direct-reading type, and may also be a spectrophotometric type. Figure 2 In this process, the light measuring device 10 measures the luminous characteristics of the test object 1 when it emits light, such as brightness and chromaticity. The light measuring device 10 is used, for example, in the inspection process of a display manufacturing line. The display emits light under predetermined luminous conditions, the luminous characteristics of the display surface are measured, such as brightness and chromaticity, and it is detected whether the display is actually emitting light under the predetermined luminous conditions.

[0042] The optical measurement device 10 includes a measurement unit 16, a first display unit 17, a first operation unit 18, a first communication unit 19, and a first control unit 15. The measurement unit 16 includes an objective lens optical system 11, a beam splitting optical system 12, a colorimetric optical system 13, and an electrical processing unit 14.

[0043] The objective lens optical system 11 includes a convex lens 11a with positive optical power, an optical attenuation filter 4, and an aperture stop 11b. The beam splitting optical system 12 includes a diffuser plate 20 with beam splitting and diffusion functions. The optical attenuation filter 4 is also called an "ND filter".

[0044] The aperture stop 11b is positioned at the rear focal point of the convex lens 11a. By setting it to be front-telecentric, it can capture light components within ±2.5 degrees of the normal to the surface under test, which serves as the display surface of the subject 1. The diffuser plate 20 is positioned behind the aperture stop 11b. The light attenuation filter 4 is positioned between the convex lens 11a and the diffuser plate 20, and is located in front of the aperture stop 11b.

[0045] The optical attenuation filter 4 is driven by the insertion / removal device 5. The insertion / removal device 5 inserts the optical attenuation filter 4 into or removes it from the optical path of the light under test 2. The insertion / removal device 5 may have, for example, a linear actuator. When the optical attenuation filter 4 is inserted into the optical path of the light under test 2, the amount of light from the light under test 2 incident on the diffuser plate 20 is reduced due to the optical attenuation filter 4. When the optical attenuation filter 4 is removed from the optical path of the light under test 2, the light under test 2 is incident on the diffuser plate 20 without a reduction in light amount.

[0046] The light attenuation filter 4 is inserted and removed according to the brightness of the test object 1. Specifically, when the test object 1 is dark (low brightness), the light attenuation filter 4 is removed from the optical path. When the test object 1 is bright (high brightness), the light attenuation filter 4 is inserted into the optical path to reduce the amount of light, thereby preventing the light receiving sensors 132a, 132b, and 132c from saturating. Thus, the intensity of the tested light 2 can be controlled within the dynamic range of the light receiving sensors 132a, 132b, and 132c, which means the dynamic range of the light measurement device 10 is expanded.

[0047] The colorimetric optical system 13 includes color filters 131a, 131b, and 131c, and light-receiving sensors 132a, 132b, and 132c. Color filters 131a, 131b, and 131c are wavelength filters and are isochromatic function filters corresponding to the X, Y, and Z tristimulus values, respectively. Light-receiving sensors 132a, 132b, and 132c are light-receiving elements used in combination with the isochromatic function filters.

[0048] As light-receiving sensors 132a, 132b, and 132c, silicon sensors are used, for example. The light received in each light-receiving sensor 132a, 132b, and 132c is converted into an electrical signal and input to the corresponding electrical processing units 14a, 14b, and 14c.

[0049] Electrical processing units 14a, 14b, and 14c perform I / V conversion, amplification, and other processing on the input electrical signals. The processed electrical signals are then input as numerical data to the first control unit 15.

[0050] The first display unit 17 and the first operation unit 18 are, for example, equipped with a liquid crystal display (LCD) with a touch panel. The first display unit 17 displays various operation screens, measurement data, etc., based on signals input from the first control unit 15. The first operation unit 18 is equipped with various operation buttons such as a numeric keypad and a start button, for receiving various input operations from the user and outputting signals to the first control unit 15.

[0051] The first communication unit 19, based on the communication control of the first control unit 15, transmits and receives various signals or data with external devices.

[0052] The first control unit 15 includes a CPU, RAM, memory, etc. The CPU is a hardware processor that reads various programs stored in the memory and loads them into the RAM, and executes various processes according to the loaded programs, thereby controlling the operation of each part of the light measuring device 10. The first control unit 15 performs calculations to set the measurement conditions based on the light emission conditions obtained from the outside.

[0053] [Operation of the optical measurement device]

[0054] Figure 3 This is a flowchart illustrating an example of the operation of the light measuring device 10. When the measurement of luminescence characteristics begins, the following operations are performed. Specifically, according to instructions from an external device or the like, the subject 1 emits light under predetermined luminescence conditions. The light measuring device 10 measures its luminescence characteristics, such as brightness and chromaticity, and confirms whether the subject 1 actually emits light under the predetermined luminescence conditions.

[0055] First, the first control unit 15 acquires the emission conditions of the subject 1 from the outside (step S1: emission condition acquisition process). At this time, the first control unit 15 functions as the emission condition acquisition unit. The emission conditions include the target brightness or chromaticity of the subject 1, the emission waveform, etc. Furthermore, the emission conditions may also include a waiting time until the subject 1 emits light at the target brightness or chromaticity. This waiting time is also called the "emission condition waiting time." Additionally, "target brightness or chromaticity" here refers to the brightness or chromaticity of the emission conditions indicated to the subject 1. When measuring the gamma value of the subject 1, multiple gamma curves exist for each driving frequency of the subject 1, and the emission conditions are set corresponding to these gamma curves. The gamma value will be described later.

[0056] The source of information on the luminescence conditions is not particularly limited; it can be the test subject 1 or other management devices. Furthermore, the measurer can also input the luminescence conditions via the first operation unit 18.

[0057] Next, the first control unit 15 sets measurement conditions based on the acquired emission conditions (step S2: measurement condition setting process). At this time, the first control unit 15 functions as a measurement condition setting unit. Measurement conditions include, for example, setting the measurement range, optimal measurement time (total exposure time), integration conditions (integration time and number of integrations), and the insertion / removal of the light attenuation filter 4. The measurement conditions are set based on the tolerance range, the emission conditions acquired by the first control unit 15, and the measurement history stored by the first control unit 15. Furthermore, an adjustment time is calculated until the set measurement conditions are met and measurement can be performed. This adjustment time is also called the "measurement condition waiting time."

[0058] In this embodiment, since the target brightness or chromaticity of the test subject 1 is known in advance, the time required to set the measurement conditions can be shortened, and the waiting time for setting the measurement conditions can also be shortened. Furthermore, since optimal measurement conditions can be set, the accuracy of the measurement can be improved. Details will be described later.

[0059] Next, the first control unit 15 causes the measuring unit 16 to measure the luminescence characteristics of the test subject 1 according to the set measurement conditions (step S3: luminescence characteristic measurement process), and then ends the operation. The first control unit 15 can also store the measurement history in a memory. At this time, the first control unit 15 functions as a storage unit. The measurement history preferably includes the measurement results and the measurement conditions associated with the measurement results.

[0060] [Composition of the management device]

[0061] The management device 30 includes a second display unit 32, a second operation unit 33, a second communication unit 34, and a second control unit 31.

[0062] The second display unit 32 and the second operation unit 33, for example, include a liquid crystal display (LCD) with a touch panel. The second display unit 32 displays various operation screens, measurement data, etc., based on signals input from the second control unit 31. The second operation unit 33 includes various operation buttons such as a numeric keypad and a start button, used to receive various input operations from the user and output signals to the second control unit 31.

[0063] The second control unit 31 includes a CPU, RAM, and memory. The CPU is a hardware processor that reads various programs stored in the memory and loads them into the RAM, then executes various processes according to the loaded programs to control the operation of each part of the management device 30. The second control unit 31 can also perform calculations for setting illumination conditions and measurement conditions. In addition, the illumination conditions and measurement conditions can also be stored in the memory.

[0064] The second communication unit 34, based on the communication control of the second control unit 31, transmits and receives various signals or data with external devices.

[0065] [Monitor Gamma Adjustment]

[0066] The optical measurement system 100 of this embodiment is preferably used, for example, in the inspection process of the production line of the display 40.

[0067] The display 40, serving as the test object, includes a light-emitting unit 42, a third communication unit 43, and a third control unit 41. The light-emitting unit 42 includes a light-emitting element such as an organic electroluminescent (EL) element. The light-emitting unit 42 emits light based on instructions from the third control unit 41. The third communication unit 43 receives various signals or data regarding the light-emitting conditions from the second communication unit 34 of the management device 30 based on communication control from the third control unit 41. The display 40 can be an organic EL display (OLED), a liquid crystal display (LCD), or a micro-LED.

[0068] The optical measurement system 100 of this embodiment is particularly preferred for measuring gamma values ​​in gamma adjustment. In devices that output image data, such as displays, "gamma value" refers to a numerical value representing the grayscale response characteristics of an image. Depending on the output device, the grayscale response characteristics of the image differ, and each output device has its own inherent gamma value. Therefore, considering the gamma value of the output device, the input values ​​(voltage, digital data values, etc.) input to the output device are corrected in advance. This operation is called "gamma correction".

[0069] To ensure accurate gamma calibration, the monitor must be manufactured according to a set gamma value. The manufacturer measures the monitor's gamma value during the inspection process. If a deviation exists between the measured value and the set value, the input / output conversion characteristics of the lookup table built into the monitor are rewritten to correct the gamma value. This series of operations involving the measurement and correction of the gamma value is collectively referred to as "gamma adjustment."

[0070] By changing the mode and drive frequency, the brightness of the display 40 is measured multiple times under different conditions, and the gamma value is calculated based on the obtained brightness measurements. In recent years, with the improvement of display performance, the number of combinations of changing modes and drive frequencies has been increasing.

[0071] For example, the modes are set to four: Mode 1 (high brightness), Mode 2, Mode 3, and Mode 4 (low brightness). For each predetermined mode and each grayscale level, the brightness of white (W), red (R), green (G), and blue (B) is measured separately. In recent years, measurements have been increasingly performed not only at a driving frequency of 60Hz but also at 90Hz. Even at a driving frequency of 90Hz, the above four modes are set, for example. The output emission waveform is not particularly limited in each mode. The output emission intensity can be constant or variable. Furthermore, the output emission intensity can be continuous or discontinuous.

[0072] Furthermore, in recent years, with the increasing performance of displays, the number of gamma adjustment points (the locations within the display where gamma values ​​need to be adjusted) has been continuously increasing. Therefore, the number of brightness measurements has increased significantly, and the time required for brightness measurement has increased substantially. Additionally, brightness changes accompanying grayscale variations can also be measured. In this case, the number of brightness measurements further increases, and the measurement time is even longer. Therefore, there is a need to shorten the time required for brightness measurement.

[0073] [Operation of the optical measurement system]

[0074] Figure 4 This is a flowchart illustrating an example of the steps in the gamma adjustment method. Once gamma adjustment begins, the following steps are performed. It should be noted that, here, steps other than the gamma measurement step are also performed by the management device 30, but they could also be performed by other devices.

[0075] First, the second control unit 31 sets the drive frequency for gamma adjustment (step S11: drive frequency setting process).

[0076] Next, the second control unit 31 sends instructions to the light measurement device 10 and the display 40 to measure the gamma value of the display 40 at the set drive frequency (step S12: gamma measurement process).

[0077] Next, the second control unit 31 determines whether the measurement result of the gamma value meets the predetermined value (step S13: gamma value confirmation process). If the second control unit 31 determines that the measurement result of the gamma value meets the predetermined value (step S13: yes), then the series of actions ends; if it determines that the measurement result does not meet the predetermined value (step S13: no), then the process proceeds to step S14.

[0078] Next, the second control unit 31 corrects the gamma value of the display 40 at the set driving frequency based on the measured gamma value (step S14: gamma correction process). Gamma value correction may involve adjusting the voltage applied to the internal electronic circuitry of the display 40, for example. The method for gamma value correction is not particularly limited, and known methods may be used. Thereafter, steps S12 to S14 are repeated until the measured gamma value meets a predetermined value, and gamma correction continues.

[0079] Figure 5 This is a flowchart illustrating an example of the actions taken when determining whether the measurement result of luminance or chromaticity in a gamma value measurement meets a predetermined value. When the determination begins, the following actions are performed.

[0080] First, the second control unit 31 acquires the target value of brightness or chromaticity in the measurement (step S15: target value acquisition process). If the data about the target value has been stored in the second control unit 31, the second control unit 31 reads the data about the target value.

[0081] Next, the second control unit 31 acquires the tolerance range of luminance or chromaticity during measurement (step S16: first tolerance range acquisition process). If data regarding the value and category of the tolerance range has already been stored in the second control unit 31, the second control unit 31 reads the data regarding the tolerance range. Furthermore, the second control unit 31 can also set the tolerance range based on the target luminance or chromaticity. Specifically, the category of the tolerance range refers to luminance or chromaticity.

[0082] Next, the second control unit 31 acquires the measurement result from the gamma measurement process S12, that is, the measured value of luminance or chromaticity (step S17: measurement result acquisition process).

[0083] Next, the second control unit 31 determines whether the acquired measurement result, i.e. the measured value of brightness or chromaticity, is within the target value and its tolerance range, i.e. whether the predetermined value is met (step S18: measurement result determination process), and ends the operation.

[0084] An upper limit can be set for the number of repetitions of steps S12 to S14. If the gamma value measurement result still does not meet the predetermined value even when the upper limit is reached, it is judged as abnormal.

[0085] When gamma adjustment is performed at multiple drive frequencies, such as 30Hz, 60Hz, and 90Hz, steps S11 to S14 are repeated for each drive frequency. Furthermore, although the drive frequency is set in step S11, in practice, multiple settings are also set for the mode, grayscale level, and adjustment point, and steps S11 to S14 are repeated for each setting.

[0086] (Gamma measurement)

[0087] The details of the gamma measurement process S12 will be described. The optical measurement device 10 or optical measurement system 100 of this embodiment can be applied to the gamma measurement process S12.

[0088] Figure 6 This is a sequence diagram illustrating an example of the operation of the optical measurement system 100 in gamma measurement. When the gamma measurement process S12 begins, the following actions are performed.

[0089] First, the second control unit 31 of the management device 30 sets the output value of the display 40 based on the set mode and grayscale (step S21: output value setting process).

[0090] Next, the second control unit 31 of the management device 30 sets the illumination conditions of the display 40 based on the set output value (step S22: illumination condition setting process). At this time, the second control unit 31 functions as the illumination condition setting unit. The illumination conditions of the display 40 may include a waiting time for the illumination conditions.

[0091] Next, the second control unit 31 of the management device 30 instructs the second communication unit 34 to send the set illumination conditions of the display 40 (step S23: illumination condition sending process).

[0092] Next, the third control unit 41 of the display 40 instructs the third communication unit 43 to receive the light emission conditions sent from the second communication unit 34 of the management device 30 (step S31: first light emission condition receiving process).

[0093] Next, the third control unit 41 of the display 40 instructs the light-emitting unit 42 to start emitting light based on the received light-emitting conditions (step S32: light-emitting start process).

[0094] Next, the first control unit 15 of the light measurement device 10 instructs the first communication unit 19 to receive the light emission conditions sent from the second communication unit 34 of the management device 30 (step S42: second light emission condition receiving process).

[0095] Next, the first control unit 15 of the optical measuring device 10 sets the measurement conditions of the optical measuring device 10 based on the received emission conditions (step S43: first measurement condition setting process). At this time, the first control unit 15 functions as a measurement condition setting unit.

[0096] Next, the first control unit 15 of the optical measurement device 10 instructs the measurement unit 16 to adjust it to meet the measurement conditions (step S44: measurement condition adjustment process). Specifically, operations such as inserting and removing the optical attenuation filter 4 and refreshing the electronic circuit to eliminate residuals are performed.

[0097] Next, the first control unit 15 of the light measurement device 10 issues an instruction to the measurement unit 16, and after confirming that the adjustment of the measurement conditions is completed, measures the light emission characteristics (e.g., brightness, chromaticity, etc.) of the display 40 (step S45: measurement process). Alternatively, the first control unit 15 of the light measurement device 10 may also instruct the light measurement device 10 to start the measurement when it is measurable, based on the waiting time of the received light emission conditions.

[0098] Next, the first control unit 15 of the optical measurement device 10 sends an instruction to the first communication unit 19 to send the measurement history (step S46: measurement history sending process).

[0099] Next, the second control unit 31 of the management device 30 sends an instruction to the second communication unit 34 to receive the measurement history sent from the first communication unit 19 of the optical measurement device 10 (step S26: measurement history receiving process). After receiving the measurement history, the second control unit 31, through the second communication unit 34 and the third communication unit 43, instructs the third control unit 41 of the display 40 to stop emitting light and to end the operation of the management device 30.

[0100] Next, the first control unit 15 of the optical measurement device 10 stores the measurement history in the memory (step S47: first measurement history storage process) and terminates the operation of the optical measurement device 10. The stored measurement history includes the measurement results and the associated measurement conditions.

[0101] Next, the third control unit 41 of the display 40 sends an instruction to the light-emitting unit 42 to stop the light emission (step S33: light emission end process), and the operation of the display 40 ends.

[0102] When measuring luminance or chromaticity in multiple modes, repeat the above steps for each mode. When measuring luminance or chromaticity at multiple gray levels, repeat the above steps for each gray level. When measuring luminance or chromaticity at multiple adjustment points, repeat the above steps for each adjustment point.

[0103] (Setting measurement conditions)

[0104] The following explains the setting of measurement conditions.

[0105] Figure 7 This is a flowchart illustrating an example of the operation of the first control unit 15 during measurement condition setting. When the setting of measurement conditions begins, the following operations are performed.

[0106] First, the first control unit 15 acquires the illumination conditions of the display 40 (step S51: illumination condition acquisition process). The illumination conditions of the display 40 can be sent by an external device such as the management device 30, or can be input by the measurer from the first operation unit 18.

[0107] Next, the first control unit 15 acquires the tolerance range in the measurement (step S52: second tolerance range acquisition process). The tolerance range can be sent by an external device such as the management device 30, or it can be input by the measurer from the first operation unit 18.

[0108] Next, the first control unit 15 acquires the measurement history (step S53: measurement history acquisition process). When the measurement history is stored in the memory of the first control unit 15, the first control unit 15 reads the measurement history. When the measurement history is stored in the memory of an external device such as a management device 30, which is different from the first control unit 15, the measurement history can also be read by the external device and acquired via the first communication unit 19. The first control unit 15 sets the measurement conditions with reference to the measurement history. Specifically, it reads the measurement result that is the same as the target brightness or chromaticity set in the light emission conditions, refers to the associated past measurement conditions, and sets various items sequentially as shown in steps S54 to S59 below.

[0109] Next, the first control unit 15 determines whether the light attenuation filter 4 is needed based on the referenced past measurement conditions (step S54: filter determination process).

[0110] As displays become more high-performance, their dynamic range widens, necessitating high-precision measurements across a broad range from high brightness (e.g., 10,000 cd / m²) to ultra-low brightness (e.g., 0.0001 cd / m²). Accurate measurements at high brightness can be achieved by using a light-attenuating filter 4.

[0111] Next, the first control unit 15 determines whether a residual exists based on the referenced past measurement conditions (step S55: residual determination process). Here, "residual" refers to the charge remaining in the electronic circuit. When the target brightness is switched from high brightness to low brightness, charge is easily left in the electronic circuit, which easily generates a residual. Therefore, it is necessary to remove the residual charge to refresh the electronic circuit and eliminate the residual.

[0112] Next, the first control unit 15 sets the measurement range based on the acquired luminescence conditions, especially the target brightness (step S56: measurement range setting process).

[0113] By setting the measurement range based on the target brightness, the optimal measurement range can be preset, thereby eliminating unnecessary steps and shortening the measurement time.

[0114] Next, the first control unit 15 sets the exposure time based on the acquired light emission conditions, particularly the target brightness (step S57: exposure time setting process). Then, the first control unit 15 sets the integration conditions, namely the number of integrations and the integration time, based on the acquired light emission conditions, particularly the target brightness (step S58: integration condition setting process). By pre-setting the integration conditions and exposure time, the pre-exposure step can be omitted. In particular, in low-brightness measurements, a longer exposure time is required; therefore, by omitting the pre-exposure step, the time can be significantly reduced. Furthermore, by pre-setting the exposure time, the time required for measurement can be calculated.

[0115] Next, the first control unit 15 calculates the waiting time until the measurement conditions are met and measurement can be performed, based on the referenced past measurement conditions (step S59: waiting time calculation process), and ends the operation. This waiting time is also referred to as the "measurement condition waiting time".

[0116] The waiting time is calculated based on the time required for the insertion and removal of the optical attenuation filter 4 (filter adjustment time) and the time required for residual elimination (residual elimination time). Since the insertion and removal of the optical attenuation filter 4 and the elimination of residuals can be performed simultaneously, the longer of the two times is the waiting time.

[0117] The pre-measurement waiting time can be calculated based on the waiting time for both illumination and measurement conditions. Here, "pre-measurement waiting time" refers to the waiting time from the indication of gamma measurement to the actual start of brightness measurement. Since the adjustment of illumination and measurement conditions can be performed simultaneously, the longer of the two waiting times is the pre-measurement waiting time.

[0118] When there is a deviation of more than a predetermined value between the target brightness or chromaticity under the illumination conditions and the actual measured brightness or chromaticity, the measurement conditions can be changed and reset based on the measurement results.

[0119] This example illustrates the steps for setting the measurement range, total exposure time, integration conditions, and tolerance range based on the acquired luminescence conditions, particularly the target brightness. Furthermore, in gamma measurements, specific luminescence conditions and specific measurement conditions can also be programmed in a standardized manner.

[0120] (1) Setting the measurement range

[0121] Set the measurement range based on the target brightness Lv and the display color.

[0122] The stimulus value conversion based on the WRGB of the display 40 is saved, and the measurement range is set after brightness correction. Table I shows an example of the relationship between the display color of the display 40, the stimulus value for measurement range switching, and the stimulus value conversion for the target brightness. Table II shows the measurable brightness range for each measurement range. Additionally, kx and kz are coefficients for converting the target brightness to stimulus values, which are set, for example, during the factory calibration of the light measurement device 10.

[0123] [Table 1]

[0124] Table I

[0125] [Table 2]

[0126] Table II

[0127] (2) Setting the synchronization frequency

[0128] Based on the following formula, the frequency to be synchronized is calculated according to the display's driving frequency and the number of frames displayed per second.

[0129] Synchronization frequency = Drive frequency ÷ Number of frames displayed per second

[0130] For example, when the monitor's drive frequency is 60Hz and the number of frames displayed per second is 1, the synchronization frequency is 60Hz. When the monitor's drive frequency is 60Hz and the number of frames displayed per second is 2, the synchronization frequency is 30Hz.

[0131] (3) Setting of total exposure time (total integration time), integration conditions (integration time and number of integrations) and tolerance range for synchronization frequency.

[0132] Within the set measurement range, set the integration conditions to maximize the signal-to-noise ratio (S / N) for the synchronization frequency. When higher precision is required for the integration conditions, calculations can be performed based on the synchronization frequency or measurement circuit settings. For measurements performed with the set integration conditions, confirm that the expected measurement results are within the tolerance range. The tolerance range can also be set based on the target brightness or chromaticity. The total exposure time can also be set using calculations or tabular values. When the tolerance range is small, the total exposure time can be extended. Table III shows an example of the relationship between synchronization frequency, total exposure time, integration time, and number of integrations.

[0133] [Table 3]

[0134] Table III

[0135] (Gamma measurement procedure: variation 1)

[0136] Figure 8 This is a timing diagram illustrating a variation 1 of the operation of the optical measurement system 100 in gamma measurement. Except for performing step S28 described below, the rest is the same as described above. Figure 6 The operation of the optical measurement system 100 shown is the same.

[0137] In Modification 1, the second control unit 31 of the management device 30 sets the light emission conditions, excluding the light emission condition waiting time, in the light emission condition setting step S22. After the light emission condition sending step S23, the second control unit 31 calculates the waiting time for the light emission conditions (step S28: waiting time calculation step). Based on the calculated waiting time, the light measuring device 10 can be instructed to start the measurement at the moment when the display 40 emits light at a predetermined brightness or color.

[0138] (Gamma measurement procedure: variation example 2)

[0139] Figure 9 This is a timing diagram illustrating a modified example 2 of the operation of the optical measurement system 100 in gamma measurement. Except for performing steps S48 and S29 described below, it is similar to the aforementioned... Figure 6 The operation of the optical measurement system 100 shown is the same.

[0140] In Modification 2, after the second measurement condition setting step S43, the first control unit 15 of the optical measuring device 10 transmits the set measurement conditions to the management device 30 via the first communication unit 19 (step S48: first measurement condition transmission step). The second control unit 31 of the management device 30 receives the measurement conditions via the second communication unit 34 (step S29: first measurement condition receiving step). Based on the received measurement conditions, at the time of measurement completion, the optical measuring device 10 is instructed to stop emitting light.

[0141] (Gamma measurement procedure: variation example 3)

[0142] Figure 10 This is a timing diagram illustrating a variation 3 of the operation of the optical measurement system 100 in gamma measurement. As shown in variation 3, the management device 30, in addition to setting the emission conditions, can also set the measurement conditions and store the measurement history. Except for performing the following steps S24, S25, S27, and S41 instead of the aforementioned steps S42, S43, and S47, the operation is the same as described above. Figure 6 The operation of the optical measurement system 100 shown is the same.

[0143] In Modification 3, in the light emission condition sending process S23, the light emission condition is sent only to the display 40.

[0144] Next, the second control unit 31 of the management device 30 sets the measurement conditions of the light measuring device 10 based on the set light emission conditions (step S24: second measurement condition setting process). At this time, the second control unit 31 functions as a measurement condition setting unit.

[0145] Next, the second control unit 31 of the management device 30 instructs the second communication unit 34 to send the set measurement conditions of the optical measurement device 10 (step S25: second measurement condition sending process).

[0146] Next, the first control unit 15 of the optical measurement device 10 instructs the first communication unit 19 to receive the measurement conditions sent from the second communication unit 34 of the management device 30 (step S41: second measurement condition receiving process). Then, the measurement condition adjustment process S44 and the measurement process S45 proceed. The second control unit 31 of the management device 30 can instruct the optical measurement device 10 to begin measurement at a measurable time based on the set emission condition waiting time and measurement condition waiting time. Then, the measurement history sending process S46 and the measurement history receiving process S26 proceed.

[0147] Next, the second control unit 31 of the management device 30 stores the received measurement history into the memory (step S27: first measurement history storage process). The second control unit 31 of the management device 30 instructs the third control unit 41 of the display 40 to stop the light emission of the display 40 via the second communication unit 34 and the third communication unit 43, and terminates the operation of the management device 30.

[0148] In this embodiment, the light measurement device 10 is a light measurement device for measuring the light emission characteristics of a test subject 1, comprising: a light emission condition acquisition unit (first control unit 15) that acquires the light emission conditions of the test subject 1 from the outside in advance; and a measurement condition setting unit (first control unit 15) that sets the measurement conditions based on the acquired light emission conditions. This shortens the time required for light measurement.

[0149] In this embodiment, the luminescence conditions include conditions related to the target brightness. This reduces the time required for brightness measurement. Furthermore, the gamma value of the subject 1 can be measured using the light measurement device 10.

[0150] In this embodiment, the luminescence conditions include conditions related to the time required from the start of luminescence on the subject 1 until the subject 1 emits luminescence at the target brightness. This allows the adjustment of the luminescence conditions and the adjustment of the measurement conditions to be performed simultaneously, thereby shortening the time required for brightness measurement. Furthermore, this allows for the determination of the optimal timing for starting the measurement.

[0151] In this embodiment, the luminescence conditions include conditions related to the driving frequency of the test subject 1. Therefore, optimal measurement conditions can be set.

[0152] In this embodiment, the emission conditions include at least one of the following: conditions related to the number of frames displayed on the subject 1 within one second and conditions related to the emission display color. Therefore, the gamma value of the subject 1 can be measured using the light measurement device 10.

[0153] In this embodiment, the measurement conditions include values ​​related to the tolerance range and category of the measured values. This allows for the setting of optimal total exposure time, integration conditions, etc.

[0154] In this embodiment, the measurement conditions include conditions related to the total exposure time. This eliminates the need for a pre-exposure step, thereby shortening the time required for light measurement. Furthermore, the measurement time can be determined.

[0155] In this embodiment, the measurement conditions include conditions related to the measurement range set based on the target brightness. Therefore, there is no need to change the measurement range and remeasure, thereby reducing the time required for light measurement.

[0156] In this embodiment, the light measurement device 10 includes a storage unit (first control unit 15) that stores measurement history that associates past measurement results with measurement conditions, and sets measurement conditions based on emission conditions and measurement history. Therefore, since optimal measurement conditions can be set, the time required for light measurement can be shortened, and accuracy can be improved.

[0157] In this embodiment, the optical measurement device 10 includes an optical attenuation filter 4, and the measurement conditions include conditions related to the insertion and removal of the optical attenuation filter 4. Therefore, measurements can be performed under optimal conditions, and the accuracy of optical measurements can be improved.

[0158] In this embodiment, the optical measurement device 10 includes an optical attenuation filter 4. During the period from when the test subject 1 begins to emit light until the test subject 1 emits light at the target brightness or chromaticity, at least a portion of the insertion and removal operation of the optical attenuation filter 4 is performed. As a result, the insertion and removal operation of the optical attenuation filter 4 can be performed simultaneously and in parallel with the adjustment of the light emission conditions, thereby shortening the time required for optical measurement.

[0159] In this embodiment, the light measurement system 100 is a light measurement system for measuring the light emission characteristics of a test subject 1, and includes: a light emission condition setting unit (second control unit 31) for setting the light emission conditions of the test subject 1; a measurement condition setting unit (first control unit 15 or second control unit 31) for setting measurement conditions based on the light emission conditions; and a measurement unit 16 for performing measurements based on the measurement conditions. This reduces the time required for light measurement.

[0160] In this embodiment, the test object 1 is a display 40. This reduces the time required to measure the luminous characteristics of the display 40 and improves accuracy.

[0161] In this embodiment, the brightness is measured at the gamma adjustment point of the test subject 1 and the gamma value is calculated. This reduces the time required to measure the gamma value of the display 40 and improves accuracy.

[0162] In this embodiment, the gamma adjustment method includes: a step of acquiring the gamma value of the display 40 using the light measurement system 100; and a step of correcting the gamma value of the display 40. This reduces the time required to adjust the gamma value of the display 40 and improves accuracy.

[0163] Furthermore, the detailed structure and operation of each device constituting the optical measurement apparatus may be appropriately modified without departing from the spirit of this disclosure.

[0164] Example

[0165] Gamma adjustment was performed using the method described above. Table IV shows a portion of the information regarding the gamma measurements performed during gamma adjustment.

[0166] [Table 4]

[0167] Table IV

[0168] The measurement modes were set to Mode 1 and Mode 2. Measurements were performed in Mode 2 after measurements were taken in Mode 1. Table IV shows the contents from the measurement step midway through Mode 1 (Measurement Step 1) to the first measurement step after switching to Mode 2 (Measurement Step 10). Measurement Step 10 indicates the step in progress. Therefore, the "-" in the brightness of the measurement result for Measurement Step 10 in Table IV indicates that a measurement is in progress.

[0169] (Waiting time in the luminescence condition)

[0170] The target brightness was changed in the following order: 400 nits, 800 nits, 1200 nits, and 1 nit. When the target brightness was changed from 400 nits to 800 nits, the wait time was set to 300 ms. When the target brightness was changed from 800 nits to 1200 nits, the wait time was set to 200 ms. Without changing the target brightness, the wait time was extremely short, set to 10 ms. Furthermore, since there was also a measurement step with a target brightness of 400 nits before measurement step 1, the wait time in the light emission conditions of measurement step 1 was set to 10 ms.

[0171] (Waiting time in measurement conditions)

[0172] The measurement conditions are set according to the brightness of each target. The filter adjustment time and residual elimination time are set based on the brightness of each target and the measurement history.

[0173] When the target brightness is changed from 400 nits to 800 nits, the adjustment time is set to 300 ms because an ND filter is inserted into the optical path of the tested light 2 in the optical measurement device 10. When the target brightness is changed from 800 nits to 1200 nits, no adjustment time is generated because the ND filter remains inserted. When the target brightness is changed from 1200 nits to 1 nit, the adjustment time is set to 300 ms because the ND filter is removed from the optical path of the tested light 2 in the optical measurement device 10.

[0174] Additionally, when the target brightness is changed from 1200 nits to 1 nit, the residual elimination time is set to 500 ms.

[0175] Since the adjustment of the optical attenuation filter and the elimination of the residual can be performed simultaneously, the waiting time under measurement conditions is determined by the longer of the optical attenuation filter adjustment time and the residual elimination time. For example, in measurement step 10, since the optical attenuation filter adjustment time is 300ms and the residual elimination time is 500ms, the waiting time under measurement conditions is 500ms.

[0176] The details of each measurement step are explained. Additionally, as... Figure 5 As shown, the measurement steps are advanced while determining whether each measurement result meets the predetermined value.

[0177] With a target brightness of 400 nits, the tolerance range was set to 1.0%, i.e., within the range of 396 to 404 nits. The brightness measurement result in step 1 was 390 nits, which was outside the tolerance range. Therefore, the display's output voltage was adjusted to change the light emission conditions, and step 2 was performed as a remeasurement. The brightness measurement result in step 2 was 403 nits, which was within the tolerance range. The target brightness was changed from 400 nits to 800 nits, and the process proceeded to the next measurement step.

[0178] With a target brightness of 800 nits, the tolerance range was set to 0.8%, i.e., within the range of 793.6 to 806.4 nits. The brightness measurement result in measurement step 3 was 793 nits. Since this was outside the tolerance range, the display's output voltage and other factors were adjusted to change the light emission conditions, and measurement step 4 was performed as a remeasurement. The brightness measurement result in measurement step 4 was 810 nits. Since this was outside the tolerance range, the display's output voltage and other factors were adjusted to change the light emission conditions, and measurement step 5 was performed as a remeasurement. The brightness measurement result in measurement step 5 was 801 nits, which was within the tolerance range. The target brightness was changed from 800 nits to 1200 nits, and the process proceeded to the next measurement step.

[0179] With a target brightness of 1200 nits, the tolerance range was set to 0.5%, i.e., within the range of 1194 to 1206 nits. The brightness measurement result in measurement step 6 was 1150 nits. Since this was outside the tolerance range, the display's output voltage was adjusted to change the light emission conditions, and measurement step 7 was performed as a remeasurement. The brightness measurement result in measurement step 7 was 1193 nits. Since this was outside the tolerance range, the display's output voltage was adjusted to change the light emission conditions, and measurement step 8 was performed as a remeasurement. The brightness measurement result in measurement step 8 was 1207 nits. Since this was outside the tolerance range, the display's output voltage was adjusted to change the light emission conditions, and measurement step 9 was performed as a remeasurement. The brightness measurement result in measurement step 9 was 1200 nits, which was within the tolerance range. The target brightness was changed from 1200 nits to 1 nit, and the process proceeded to the next measurement step, 10.

[0180] In existing gamma measurements, the display first emits light at the target brightness. Then, the light measurement device sets and adjusts the measurement conditions according to the display brightness. Therefore, in addition to the waiting time until the emission conditions are met, a further waiting time is required until the measurement conditions are met, serving as the pre-measurement waiting time. For example, as shown in Table IV, in measurement step 3, a total of 600ms is required for the pre-measurement waiting time (300ms) and the measurement condition waiting time (300ms). In measurement step 10, a total of 1300ms is required for the pre-measurement waiting time (800ms) and the measurement condition waiting time (500ms).

[0181] On the other hand, in the gamma measurement of this embodiment, the light measuring device 10 is adjusted to the set measurement conditions during the period until the display emits light at the target brightness. Therefore, the waiting time before measurement only needs to be the longer of the waiting time until the light emission conditions are met and the waiting time until the measurement conditions are met, thereby shortening the waiting time before measurement.

[0182] For example, as shown in Table IV, in measurement step 3, the waiting time before measurement was previously 600ms, while in this embodiment it is 300ms, indicating a reduction in time. Furthermore, in measurement step 10, the waiting time before measurement was previously 1300ms, while in this embodiment it is 800ms, indicating a reduction in time.

[0183] Industrial availability

[0184] According to this disclosure, the measurement time in the optical measurement device can be shortened, which in turn shortens the time used for gamma adjustment.

[0185] [Explanation of reference numerals in the attached figures]

[0186] 1: Subject; 2: Test light; 4: Optical attenuation filter; 5: Insertion / removal device; 10: Optical measurement device; 11: Objective lens optical system; 11a: Convex lens; 11b: Aperture stop; 12: Beam splitting optical system; 13: Color measurement optical system; 131: Color filter; 132: Light receiving sensor; 14: Electrical processing unit; 15: First control unit; 16: Measurement unit; 17: First display unit; 18: First operation unit; 19: First communication unit; 20: Diffuser plate; 30: Management device; 31: Second control unit; 32: Second display unit; 33: Second operation unit; 34: Second communication unit; 40: Display; 41: Third control unit; 42: Light emission unit; 43: Third communication unit.

Claims

1. A photometric device for measuring the luminescence characteristics of a test object, comprising: The luminescence condition acquisition unit acquires the luminescence conditions of the subject from the outside in advance; and The measurement condition setting unit sets the measurement conditions based on the acquired emission conditions.

2. The optical measurement device according to claim 1, wherein, The luminescence conditions include those related to the target brightness.

3. The optical measurement device according to claim 2, wherein, The luminescence conditions include conditions related to the time required from the start of luminescence by the subject until the subject emits luminescence at the target brightness.

4. The optical measurement device according to claim 1, wherein, The luminescence conditions include conditions related to the driving frequency of the subject.

5. The optical measurement device according to claim 1, wherein, The emission conditions include at least one of the following: conditions related to the number of frames displayed on the subject within one second and conditions related to the emission display color.

6. The optical measurement device according to claim 1, wherein, The measurement conditions include conditions related to the tolerance range and category of the measured values.

7. The optical measurement device according to claim 1, wherein, The measurement conditions include those related to the total exposure time.

8. The optical measurement device according to claim 2, wherein, The measurement conditions include those related to the measurement range set based on the target brightness.

9. The optical measurement device according to claim 1, wherein, The optical measurement device includes a storage unit that stores measurement history that associates past measurement results with measurement conditions. The optical measurement device sets the measurement conditions based on the emission conditions and the measurement history.

10. The optical measurement device according to claim 1, wherein, The optical measurement device has an optical attenuation filter. The measurement conditions include those related to the insertion and removal of the optical attenuation filter.

11. The optical measurement device according to claim 1, wherein, The optical measurement device has an optical attenuation filter. During the period from when the subject begins to emit light until the subject emits light at the target brightness or chromaticity, at least a portion of the insertion and removal of the light attenuation filter is performed.

12. A photometric system for measuring the luminescence properties of a test subject, comprising: The luminescence condition setting unit sets the luminescence conditions of the subject; The measurement condition setting unit sets measurement conditions based on the emission conditions; and The measurement unit performs measurements based on the aforementioned measurement conditions.

13. The optical measurement system according to claim 12, wherein, The object being examined is a monitor.

14. The optical measurement system according to claim 13, wherein, The brightness is measured at the gamma adjustment point of the subject and the gamma value is calculated.

15. A gamma adjustment method, comprising: The step of acquiring the gamma value of the display using the optical measurement system of claim 14; and The process of correcting the gamma value of the display.

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