TESTING DEVICE, TESTING PROCEDURES AND PROGRAM

Abstract

A test device is provided, comprising: a light source, an electrical measurement unit that measures a photoelectric signal received from a light-emitting test target element that photoelectrically converts light emitted by the light source, and a computation unit that calculates a pseudo-external quantum yield that correlates with the inherent external quantum yield of the light-emitting test target element, based on the irradiance of the light emitted by the light source onto the light-emitting test target element, a light emission wavelength relating to the light emission of the light-emitting test target element, and the photoelectric signal measured from the light-emitting test target element.The computation unit can calculate an estimate of the inherent external quantum yield of the light-emitting test target element, obtained from a light emission test, from the pseudo-external quantum yield of the light-emitting test target element using a correction coefficient based on the pseudo-external quantum yield calculated in advance for a light-emitting reference element and the inherent external quantum yield calculated in advance for a light emission test of the light-emitting reference element.

Description

BACKGROUND 1. TECHNICAL FIELD

[0001] The present invention relates to a test device, a test method and a program. 2. STATE OF THE ART

[0002] Patent Document 1 describes: "A solar cell was characterized as follows. The external quantum efficiency (EQE) was estimated from the cell responses at different wavelengths (measured using a white-light halogen lamp in combination with a band-pass filter)." (

[0121] ). CITATION LISTPATENT DOCUMENT

[0003] Patent Document 1: Japanese Patent Application Publication No. 2021-9950 SUMMARY

[0004] In a first aspect of the present invention, a test device is provided. The test device comprises: a light source, an electrical measurement unit that measures a photoelectric signal obtained from a test target light-emitting element that photoelectrically converts light emitted from the light source, and a calculation unit that calculates a pseudo external quantum efficiency that has a correlation with the inherent external quantum efficiency of the test target light-emitting element based on the irradiation intensity of the light emitted from the light source to the test target light-emitting element, a light emission wavelength related to the light emission of the test target light-emitting element, and the photoelectric signal measured from the test target light-emitting element.

[0005] In the test device described above, the calculation unit may calculate an estimated value of the inherent external quantum efficiency of the test target light-emitting element obtained from a light emission test from the pseudo-external quantum efficiency of the test target light-emitting element using a correction coefficient based on the pseudo-external quantum efficiency calculated in advance for a reference light-emitting element and the inherent external quantum efficiency calculated in advance for a light emission test of the reference light-emitting element.

[0006] For each of the test devices described above, the reference light-emitting element may be an ideal light-emitting element that corresponds to a design value of the test target light-emitting element, or a light-emitting element included in the same production batch as the test target light-emitting element and that meets a predetermined acceptance reference.

[0007] In each of the test devices described above, the light emission wavelength concerning the light emission of the test target light-emitting element may be a wavelength corresponding to a design value of the reference light-emitting element, a wavelength measured in advance by the light emission test of the reference light-emitting element, or a wavelength in accordance with a design value of the test target light-emitting element.

[0008] Each of the test devices described above may further include a light emission control unit that causes the reference light-emitting element to emit light. Each of the test devices described above may further include a light measurement unit that measures the wavelength and light emission intensity of the light emitted by the reference light-emitting element. In each of the test devices described above, the calculation unit may calculate the pseudo-external quantum efficiency of the reference light-emitting element based on the radiant intensity of the light emitted from the light source to the reference light-emitting element, the wavelength of the reference light-emitting element measured as the light emission wavelength related to the light emission of the test target light-emitting element, and the measured photoelectric signal of the reference light-emitting element.For each of the test devices described above, the calculation unit can calculate the inherent external quantum efficiency of the reference light-emitting element based on the wavelength and light emission intensity measured by the reference light-emitting element and the current applied to the reference light-emitting element by the light emission control unit. For each of the test devices described above, the calculation unit can calculate the pseudo-external quantum efficiency by dividing the inherent external quantum efficiency.

[0009] Each of the test devices described above may further comprise an optical system that irradiates the reference light-emitting element with light incident in one direction from the light source and irradiates the light measuring unit with light incident in another direction from the reference light-emitting element.

[0010] In each of the test devices described above, the electrical measurement unit can measure the photoelectric signal obtained from each of a plurality of test target light-emitting elements that collectively photoelectrically convert light emitted from the light source. In each of the test devices described above, the calculation unit can calculate the pseudo external quantum efficiency of each of the plurality of test target light-emitting elements based on the irradiation intensity of the light emitted from the light source to the plurality of test target light-emitting elements, the light emission wavelength of the plurality of test target light-emitting elements, and the photoelectric signal measured for each of the plurality of test target light-emitting elements.

[0011] In each of the test devices described above, the calculation unit may calculate an estimated value of the inherent external quantum efficiency of each of the plurality of test target light-emitting elements obtained from a light emission test from the pseudo-external quantum efficiency of each of the plurality of test target light-emitting elements by using a correction coefficient based on the pseudo-external quantum efficiency calculated in advance for a reference light-emitting element and the inherent external quantum efficiency calculated in advance for a light emission test of the reference light-emitting element.

[0012] In each of the test devices described above, the calculation unit may use the correction coefficient that varies depending on a production batch containing the plurality of test target light-emitting elements.

[0013] Each of the test devices described above may further include a determination unit that determines the quality of each of the plurality of test target light-emitting elements based on the estimated value of the inherent external quantum efficiency of each of the plurality of test target light-emitting elements.

[0014] Each of the test devices described above may further include a light emission control unit that causes the plurality of test target light-emitting elements to collectively emit light. Each of the test devices described above may further include a light measurement unit that measures, as the light emission wavelength concerning the light emission of the plurality of test target light-emitting elements, a wavelength of the combined light obtained by combining the light emitted by each of the plurality of test target light-emitting elements.Each of the test devices described above may further include an optical system that irradiates the plurality of test target light-emitting elements with light incident from the light source in one direction and irradiates the light measuring unit with combined light obtained by combining the light incident from each of the plurality of test target light-emitting elements in another direction.

[0015] In a second aspect of the present invention, a testing method is provided. In each of the test devices described above, the testing method comprises irradiating a test target light-emitting element with light emitted from a light source, measuring a photoelectric signal obtained by the test target light-emitting element photoelectrically converting irradiated light, and calculating a pseudo-external quantum efficiency that has a correlation with the inherent external quantum efficiency of the test target light-emitting element based on the irradiation intensity of the light irradiated from the light source to the test target light-emitting element, a light emission wavelength related to the light emission of the test target light-emitting element, and the measured photoelectric signal of the test target light-emitting element.

[0016] In a third aspect of the present invention, a program is provided. The program causes a test device that tests a light-emitting element to perform the following: irradiate a test target light-emitting element with light emitted from a light source, measure a photoelectric signal obtained from the test target light-emitting element that photoelectrically converts irradiated light, and calculate a pseudo-external quantum efficiency that has a correlation with the inherent external quantum efficiency of the test target light-emitting element based on the irradiation intensity of the light emitted from the light source onto the test target light-emitting element, a light emission wavelength related to the light emission of the test target light-emitting element, and the measured photoelectric signal of the test target light-emitting element.

[0017] The summary clause does not necessarily describe all necessary features of the embodiment of the present invention. Furthermore, the invention may also be a subcombination of the features described above. SHORT DESCRIPTION OF THE DRAWING Fig. 1 is an example of an overall view showing a schematic of a test device 100 for testing a plurality of LEDs 10. Fig. 2 is an example of the overall view showing the scheme of the tester 100 for testing the plurality of LEDs 10. Fig. 3 is an example of a flowchart for explaining the flow of a test method by the test device 100. Fig. Figure 4 shows an example of a computer 1200 in which various aspects of the present invention may be embodied in whole or in part. DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0018] Embodiments of the present invention are described below. However, the following embodiments do not represent a limitation of the invention according to the claims. Furthermore, not all combinations of features described in the embodiments are essential to the solution of the invention.

[0019] The Fig. 1 and Fig. 2 are examples of an overall view showing a schematic of a test device 100 for testing a plurality of LEDs 10. The Fig. 1 and Fig. 2 shows an X-axis, a Y-axis, and a Z-axis orthogonal to each other. A rightward direction relative to a paper surface is defined as the positive direction of the X-axis, an upward direction relative to the paper surface is defined as the positive direction of the Z-axis, and a depth direction relative to the paper surface is defined as the positive direction of the Y-axis.

[0020] Using the photoelectric effect of the light-emitting element, the test device 100 calculates a pseudo-external quantum efficiency that correlates with the inherent external quantum efficiency of the light-emitting element based on the photoelectric signal output from the light-irradiated light-emitting element. The test device 100 according to the present embodiment irradiates an LED group in which the plurality of LEDs 10 are formed on a wafer 15, which is, for example, an LED wafer, together with light to calculate the pseudo-external quantum efficiency of each LED 10 based on the photoelectric signal output from each LED 10. The test device 100 according to the present embodiment also calculates an estimated value of the inherent external quantum efficiency of each LED 10 from the pseudo-external quantum efficiency of each LED 10.The test device 100 according to the present embodiment tests the optical properties of the LED 10 by calculating the external quantum efficiency of the LED 10 in this way.

[0021] In the present embodiment, the LED 10 is a micro-LED with a dimension of 100 µm or less. Note that instead of the micro-LED, the LED 10 may be a mini-LED with a dimension greater than 100 µm and equal to or less than 200 µm, an LED with a dimension greater than 200 µm, or another light-emitting element such as an LD. These are examples of a test target light-emitting element and a reference light-emitting element.

[0022] In the present embodiment, the plurality of LEDs 10 on the wafer 15 are not electrically connected to each other. The LED array is a back-emitting type in which the light-emitting surfaces of the plurality of LEDs 10 face the wafer 15, and the wafer 15 transmits light. Two terminals 11 are formed on each LED 10 at a distance from each other in the Y-axis direction. Each terminal 11 of the plurality of LEDs 10 does not face the wafer 15. Note that in the back-emitting type LED array as in the present embodiment, the plurality of LEDs 10 and the wafer 15 on which the plurality of LEDs 10 are mounted may be collectively referred to as a wafer.Note that the LED array may be a front-emission type in which the light-emitting surfaces of the plurality of LEDs 10 do not face the wafer 15, and in this case, the wafer 15 does not need to transmit light, and each terminal 11 of the plurality of LEDs 10 does not need to face the wafer 15 or may face the wafer 15. When each terminal 11 of the plurality of LEDs 10 faces the wafer 15, a via extending in a Z-axis direction in the wafer 15 may be formed at the position of each terminal 11 to bring a power supply probe into contact with each terminal 11.

[0023] The plurality of LEDs 10 may be formed on a wafer provided with electrical leads or on a glass-based panel (PLP) having a substantially rectangular outer shape and may be electrically connected to one another to form units or cells.

[0024] For example, the test device 100 according to the present embodiment includes an arrangement unit 110, an electrical connection unit 120, a light source 130, an optical system 140, an electrical measurement unit 150, a light emission control unit 160, a light measurement unit 170, a calculation unit 180, a determination unit 190, a storage unit 200, and a shielding unit 210. Fig. 1 and Fig. 2 the signal flow between the components is indicated by black arrows.

[0025] On the array unit 110, the LED array is arranged on the positive direction side of the Z-axis. The LED array containing a plurality of test target LEDs 10 is arranged on the array unit 110. Furthermore, the array unit 110 may have one or more individual reference LEDs 10 arranged directly thereon, or may have an LED array with one or more reference LEDs 10 arranged thereon.

[0026] The arrangement unit 110 has, in the example shown, a substantially circular outer shape in a plan view from the Z-axis direction, but may also have a different outer shape. The arrangement unit 110 has a holding function, for example, a vacuum chuck, an electrostatic chuck, and the like, and holds the wafer 15 of the arranged LED group. The arrangement unit 110 has a through-hole 111 in the central portion of an XY plane so that, for example, light passing from the light source 130 through the wafer 15 and irradiated onto the plurality of LEDs 10, or light emitted from the plurality of LEDs 10 and passing through the wafer 15 is not blocked. The arrangement unit 110 holds the wafer 15 around the through-hole 111. It should be noted that in the Fig. 1 and Fig. 2 the through hole 111 is indicated by a dashed line.

[0027] The electrical connection unit 120 is, for example, a probe board (probe substrate) and is electrically connected to the terminal 11 of each of the plurality of LEDs 10 included in the LED group to be tested. Furthermore, the electrical connection unit 120 according to the present embodiment is also electrically connected to each terminal 11 of one or more individual reference LEDs 10 or each terminal 11 of the LED group including one or more reference LEDs 10.

[0028] The electrical connection unit 120 includes a substrate 121 and a plurality of probes 123. An electrical circuit and a plurality of electrical wirings are provided on the substrate 121. The plurality of probes 123 are provided on one main surface of the substrate 121 and protrude from the one main surface of the substrate 121. Each of the plurality of probes 123 can contact the terminal 11 of each LED 10 in a state where the substrate 121 faces the LED group on the array unit 110.

[0029] The electrical connection unit 120 moves two-dimensionally in an XY plane and moves up and down in the Z-axis direction. Fig. 1 and Fig. In Figure 2, the direction of movement of the electrical connection unit 120 is indicated by a white arrow. For example, the electrical connection unit 120 moves such that the plurality of LEDs 10 are arranged between the electrical connection unit 120 and the light source 130, and brings the plurality of probes 123 into contact with respective terminals 11 of the plurality of LEDs 10 from the positive Z-axis direction side of the wafer 15. The other end of each probe 123, on the opposite side of an end in contact with the terminal 11, is electrically connected to the electrical leads provided on the substrate 121. The electrical leads of each probe 123 extend from the side surface of the substrate 121 and are electrically connected to the electrical measurement unit 150 and the light emission control unit 160.

[0030] The light source 130 irradiates one or more LEDs 10 with light. In the present embodiment, as shown in Fig. 1, the light source 130 irradiates one or more LEDs 10 with light via the optical system 140. In Fig. 1, the light emitted by the light source 130 is represented by hatching.

[0031] The light source 130 is, for example, a white light source or a light source that emits light of a specific wavelength. When the light source 130 that is a white light source is used, a filter that filters light in the infrared range may be arranged between the light source 130 and the LED 10 to prevent the LED 10 from heating to a high temperature. When the light source 130 that emits light of a specific wavelength is used, the light source 130 may be set to emit light of a response wavelength of the LED 10, that is, light of a wavelength at which the LED 10 can output a photoelectric signal. For example, if the design values ​​of the light emission wavelength and the response wavelength of the LED 10 are 446 nm and 560 nm, the light source 130 may be set to emit light in a wavelength range of 560 nm ± several nm.When using the light source 130 that emits light at the response wavelength of the LED 10, the energy efficiency can be improved compared to that of the white light source because the light source 130 does not emit light at a wavelength different from the response wavelength of the LED 10. In this case, for example, a filter that filters light in an infrared range, which is a different wavelength range than the response wavelength of the LED 10, can be eliminated.

[0032] The light source 130 may be a surface light source capable of uniformly irradiating a plane on which an irradiation target is positioned. In this case, the irradiation intensity ([mW]) of the light irradiated from the light source 130 to each of the plurality of LEDs 10 on the array unit 110 may be calculated in advance by calculating the irradiation intensity per unit area ([mW / cm 2]) of the light emitted by the light source 130 with the area ([cm 2]) of each LED 10 and stored in the storage unit 200. Alternatively, the light source 130 may emit light with an in-plane light intensity distribution, and in this case, the light intensity distribution may be measured in advance and stored in the storage unit 200. For example, the irradiation intensity of the light radiated from the light source 130 to each position of the plurality of LEDs 10 on the array unit 110 may be measured in advance and stored in the storage unit 200, and the irradiation intensity for each position may be used for the external quantum efficiency calculation described above. Note that the irradiation intensity of the light radiated from the light source 130 to each of the plurality of LEDs 10 shall be the irradiation intensity of the light having the response wavelength of the LED 10 among the light emitted from the light source 130.For example, if the light source 130 is a white light source, the irradiation intensity of the light at the response wavelength of the LED 10 can be calculated by multiplying the irradiation intensity of the light emitted by the light source 130 in the entire wavelength range by the ratio of the relative intensity of the response wavelength of the LED 10 when the total intensity in the entire wavelength range is 1. Note that the light source 130 may be capable of adjusting the irradiation time, wavelength, intensity, and the like of the light irradiated onto the target.

[0033] The optical system 140 illuminates one or more LEDs 10 with light incident from the light source 130. As shown in the Fig. 1 and Fig. 2, the optical system 140 according to the present embodiment is configured such that one side is connected to the light source 130 and the light measuring unit 170, and the other side faces the LED group on the array unit 110. The optical system 140 is a group of optical elements common to the light source 130 and the light measuring unit 170. The optical system 140 enables the measurement of photoelectric signals and the wavelength for the LED 10 using bidirectional optical paths. Specifically, the optical system 140 irradiates the LED 10 with light incident from the light source 130 in one direction and irradiates the light measuring unit 170 with light incident from the LED 10 in another direction.

[0034] Specifically, as shown in FIG. 1, the optical system 140 according to the present embodiment diffuses the light emitted from the light source 130 so that the plurality of LEDs 10 are irradiated together with the light emitted from the light source 130. That is, the area onto which the light emitted from the light source 130 via the optical system 140 is projected on the XY plane on the array unit 110 covers at least the plurality of LEDs 10 of the LED group.

[0035] The optical system 140 according to the present embodiment also irradiates the light measuring unit 170 with combined light obtained by combining the light emitted from each of the plurality of LEDs 10. In Fig. 2 is the combined light from the LEDs 10 is indicated by hatching. As in Fig. 2, the optical system 140 focuses diffused light emitted by the plurality of LEDs 10 so that the light is guided to the light measuring unit 170. As shown in Fig. 2, the optical system 140 according to the present embodiment guides the light emitted from the plurality of LEDs 10 to both the light source 130 and the light measuring unit 170. Alternatively, however, the optical system 140 may be configured to guide the light emitted from the plurality of LEDs 10 only to the light measuring unit 170 and not to the light source 130.

[0036] The optical system 140 according to the present embodiment includes a bifurcated light guide 141. The bifurcated light guide 141 is a Y-shaped light guide. The end portions of the bifurcated light guide 141 on the branching side are connected to the light source 130 and the light measuring unit 170. Instead of the bifurcated light guide 141, the optical system 140 may include a multi-branched light guide, such as a triple-branched light guide or a quadruple-branched light guide. In this case, the test device 100 may include two or more light sources 130, and a light source 130 may be connected to each end portion of the multi-branched light guide on the branching side. In this case, the optical system 140 may combine light emitted from the plurality of light sources 130 that emit light in different wavelength bands and irradiate the plurality of LEDs 10.For example, the optical system 140 may combine light emitted from three light sources 130 that emit light of respective response wavelengths of RGB of the LED 10 and irradiate the LED 10. When the light source 130 emits light of a specific wavelength band, the plurality of light sources 130 are connected to the optical system 140 in this way, so that the wavelength bandwidth of the light irradiated to the LED 10 can be expanded and the LED 10 can be caused to perform photoelectric conversion more reliably.

[0037] The optical system 140 may further comprise a lens unit 143 containing one or more lenses, and the lens unit 143 is arranged in an optical path in the optical system 140. In addition, the lens unit 143, as shown in Fig. 2, the diffused light emitted from the plurality of LEDs 10 and causes the light to enter the bifurcated light guide 141.

[0038] In the test device 100, the optical system 140, the light source 130, and the light measuring unit 170 are configured to be interconnected, so that the photoelectric signal measurement and the wavelength measurement for the plurality of LEDs 10 are performed bidirectionally using the common optical system 140. When the test device 100 finishes either the photoelectric signal measurement or the wavelength measurement and starts another one, it is not necessary to change a device configuration or move the LED 10.

[0039] The electrical measurement unit 150 measures a photoelectric signal obtained from the test target LED 10 by photoelectrically converting the light emitted by the light source 130. The electrical measurement unit 150 according to the present embodiment measures a photoelectric signal obtained from each of the plurality of test target LEDs 10 by photoelectrically converting the light collectively emitted by the light source 130. The electrical measurement unit 150 according to the present embodiment further measures a photoelectric signal obtained from one or more reference LEDs 10 that photoelectrically convert the light emitted by the light source 130.

[0040] More specifically, the electrical measurement unit 150 measures a current value of the current output by each LED 10 via the electrical connection unit 120. The electrical measurement unit 150 outputs the current value measured for each LED 10 to the calculation unit 180. Note that the electrical measurement unit 150 may measure a voltage value corresponding to the current value instead of the current value of the current output by the LED 10.

[0041] The light emission control unit 160 causes the LED 10 to emit light by supplying a current or voltage of a predetermined magnitude to the LED 10. The light emission control unit 160 according to the present embodiment supplies a current or voltage of a predetermined magnitude to the plurality of test target LEDs 10 via the electrical connection unit 120, thereby causing the plurality of test target LEDs 10 to collectively emit light. The light emission control unit 160 according to the present embodiment further causes one or more reference LEDs 10 to emit light.

[0042] The light measuring unit 170 measures the wavelength of the light emitted by the LED 10. The light measuring unit 170 according to the present embodiment measures the wavelength of the combined light received via the optical system 140 and obtained by combining the light emitted by each of the plurality of LEDs 10. The combined light obtained by combining the light emitted by each of the plurality of LEDs 10 is an example of the light emission wavelength related to the light emission of the plurality of test target LEDs 10. The light measuring unit 170 can measure the wavelengths of the light emitted by one or more LEDs 10 in the group for each group obtained by dividing all the test target LEDs 10 into a plurality of groups. Furthermore, the light measuring unit 170 can individually measure the wavelength of the light emitted by each of the plurality of test target LEDs 10.The light measuring unit 170 according to the present embodiment further measures the wavelength and the light emission intensity of the light emitted by one or more reference LEDs 10.

[0043] The light measuring unit 170 according to the present embodiment includes, for example, a wavelength measuring device. The light measuring unit 170 can measure the wavelength of the combined light emitted by the plurality of LEDs 10 and indicate the intensity distribution of the wavelength of the combined light. The light measuring unit 170 can indicate the peak wavelength and the half-width of the combined light based on the intensity distribution of the combined light and can measure a main wavelength corresponding to a color when the combined light is seen with the eyes. The light measuring unit 170 can include a spectrometer, an optical spectrum analyzer, or the like instead of the wavelength measuring device. The light measuring unit 170 outputs the measured wavelength or light emission intensity to the calculation unit 180.

[0044] The calculation unit 180 calculates a pseudo-external quantum efficiency that correlates with the inherent external quantum efficiency of the test target LED 10. Specifically, the calculation unit 180 calculates the pseudo-external quantum efficiency based on the irradiation intensity with which the target LED 10 was irradiated by the light source 130, the light emission wavelength related to the light emission of the test target LED 10, and the measured photoelectric signal of the test target LED 10. The calculation unit 180 further calculates an estimated value of the inherent external quantum efficiency obtained from a light emission test of the test target LED 10 from the pseudo-external quantum efficiency of the test target LED 10.

[0045] The calculation unit 180 according to the present embodiment calculates the pseudo-external quantum efficiency of each of the plurality of test target LEDs 10. More specifically, the calculation unit 180 calculates the pseudo-external quantum efficiency of each of the plurality of test target LEDs 10 based on the irradiation intensity with which the plurality of test target LEDs 10 are irradiated by the light source 130, the light emission wavelength related to the light emission of the plurality of test target LEDs 10, and the photoelectric signal measured for each of the plurality of test target LEDs 10. The calculation unit 180 further calculates an estimated value of the inherent external quantum efficiency obtained from the light emission test of each of the plurality of test target LEDs 10 from the pseudo-external quantum efficiency of the plurality of test target LEDs 10.

[0046] The calculation unit 180 can acquire data on the irradiation intensity with which one or more test target LEDs 10 are irradiated by the light source 130, for example, from outside the test device 100 through a user input, and store the data in the storage unit 200. Note that the irradiation intensity with which one or more test target LEDs 10 are irradiated by the light source 130 can be measured by placing the light measuring unit 170 instead of the LED group on the arrangement unit 110 in the test device 100 during testing.

[0047] For example, the calculation unit 180 uses the wavelength of the combined light of the plurality of LEDs 10 input from the light measuring unit 170 as the light emission wavelength with respect to the light emission of the plurality of test target LEDs 10. Alternatively, the calculation unit 180 may use the wavelength of the reference LED 10 input from the light measuring unit 170 as the light emission wavelength with respect to the light emission of one or more test target LEDs 10.

[0048] The reference LED 10 described above may be the LED 10 that has excellent light emission characteristics that can be compared with the light emission characteristics of the test target LED 10. For example, the reference LED 10 may be an ideal light-emitting element that corresponds to the design value of the test target LED 10, or it may be an LED 10 that meets a predetermined acceptance reference and is included in the same production batch as the test target LED 10. For example, the predetermined acceptance reference may be defined for each user who manufactures and sells the test target LED 10.

[0049] The pseudo-external quantum efficiency described above is calculated using a derivative formula: EQE = [P / (I×E)]×100, similar to the well-known inherent external quantum efficiency. However, while the inherent external quantum efficiency is based on the light emission efficiency, the pseudo-external quantum efficiency is based on the light reception efficiency, and thus the inherent external quantum efficiency and the pseudo-external quantum efficiency have different values ​​from each other. In the derivation formula described above, when deriving the inherent external quantum efficiency, EQE is the inherent external quantum efficiency ([%]), P is the light emission intensity ([mW]) of the element, I is the value of the current ([mA]) input to the element, and E is the energy of light and a value ([eV]) obtained by dividing the product (1240 [nm eV]) of the Planck constant and a light flux in vacuum by the light emission wavelength ([nm]) of the element.In the derivation of the pseudoexternal quantum efficiency, EQE is the pseudoexternal quantum efficiency ([%]), P is the irradiation intensity ([mW]) of the light irradiated onto the element, I is a current value ([mA]) of the photoelectric signal output by the element, and E is the light energy and the value ([eV]) obtained by dividing the product (1240 [nm eV]) of the Planck constant and the light flux in vacuum by the light emission wavelength ([nm]) of the element.

[0050] It is understood that the pseudo-external quantum efficiency has a positive correlation with the inherent external quantum efficiency. Therefore, the light-emitting characteristics of the light-emitting element can be evaluated using the pseudo-external quantum efficiency. Furthermore, a correlation coefficient of the light-emitting element can be obtained, for example, by dividing the inherent external quantum efficiency of a particular light-emitting element by the pseudo-external quantum efficiency of the light-emitting element. The correlation coefficient between the pseudo-external quantum efficiency and the inherent external quantum efficiency of the light-emitting element may be different for each design value of the light-emitting element, that is, it may be different for each production batch of the light-emitting element.

[0051] In this regard, the calculation unit 180 according to the present embodiment uses a correction coefficient calculated in advance as a correlation coefficient corresponding to the test target LED 10 to calculate the estimated value of the inherent external quantum efficiency obtained from the light emission test of the test target LED 10 from the pseudo-external quantum efficiency of the test target LED 10. The calculation unit 180 uses the correction coefficient, which varies depending on the production batch containing one or more test target LEDs 10. Note that the plurality of LEDs 10 formed on the same wafer 15 are LEDs 10 manufactured based on the same design value and are LEDs 10 included in the same production batch. The calculation unit 180 outputs the estimated value of the inherent external quantum efficiency to the determination unit 190.

[0052] The determination unit 190 determines the quality of each of the plurality of test target LEDs 10 based on the estimated value of the inherent external quantum efficiency of each of the plurality of test target LEDs 10. For example, the determination unit 190 may determine the quality of each of the plurality of test target LEDs 10 by comparing it with the inherent external quantum efficiency of the reference LED 10 stored in the storage unit 200, that is, by comparing it with a threshold value that is a predetermined acceptance reference. For example, based on the statistical value of the inherent external quantum efficiency of the plurality of test target LEDs 10, the determination unit 190 may indicate the LED 10 whose inherent external quantum efficiency is an outlier and determine the LED 10 as deficient.Furthermore, the determination unit 190 may exclude the LED 10 determined to have a deficient inherent external quantum efficiency from the targets of the subsequent test.

[0053] The shielding unit 210 shields light other than the light emitted by the light source 130 and the LED 10. The surface of the shielding unit 210 is completely black in the present embodiment to prevent irregular light reflection on the surface. Furthermore, the shielding unit 210, as shown in Fig. 1, is configured to form a sealed space by the lens unit 143, the array unit 110, and the wafer 15, and this structure shields light other than the light emitted from the light source 130 and the LED 10.

[0054] Fig. 3 is an example of a flowchart for explaining a flow of a test method by the test device 100. The Fig. The operation sequence shown in Fig. 3 is started when, for example, a user inputs inputs to the test device 100 to start a test of the LED group in a state where the LED group is arranged on the arrangement unit 110.

[0055] The test device 100 calculates the inherent external quantum efficiency of the reference LED 10 based on the light emission test of the reference LED 10 (step S101). Specifically, in a state where one or more reference LEDs 10 are arranged on the arrangement unit 110, the light emission control unit 160 of the test device 100 supplies current of a predetermined intensity to the one or more reference LEDs 10 via the electrical connection unit 120, thereby causing these LEDs 10 to emit light. The light measurement unit 170 receives the light emitted from the one or more reference LEDs 10 via the optical system 140, measures the wavelength and light emission intensity of the received light, and outputs a measurement result to the calculation unit 180. The wavelength of the light may, for example, be the mean wavelength of the combined light emitted by the plurality of reference LEDs 10.

[0056] The calculation unit 180 calculates the inherent external quantum efficiency of the reference LED 10 based on the measured wavelength and light emission intensity of the reference LED 10 and the current input to the reference LED 10 from the light emission control unit 160. For example, the calculation unit 180 calculates the inherent external quantum efficiency of the reference LED 10 by referring to the inherent external quantum efficiency derivation formula stored in the storage unit 200.

[0057] The test device 100 calculates the pseudo external quantum efficiency of the reference LED 10 based on the photoelectric conversion test of the reference LED 10 (step S103). Specifically, the light source 130 of the test device 100 irradiates one or more reference LEDs 10 with light of a predetermined irradiation intensity via the optical system 140. The electrical measurement unit 150, via the electrical connection unit 120, measures a photoelectric signal obtained by photoelectrically converting the light emitted from each of the one or more reference LEDs 10 and outputs the measurement result to the calculation unit 180.The calculation unit 180 calculates the pseudo external quantum efficiency of each of the one or more reference LEDs 10 based on the irradiation intensity of the light radiated from the light source 130 to the one or more reference LEDs 10, wherein the wavelength of the one or more reference LEDs 10 measured in step S101 relates to the light emission of the test target LED 10 as the light emission wavelength, and the measured photoelectric signal of each of the one or more reference LEDs 10.

[0058] The test device 100 calculates the correction coefficient described above (step S105). Specifically, the calculation unit 180 of the test device 100 calculates the correction coefficient by dividing the pseudo-external quantum efficiency of each of the one or more reference LEDs 10 by the inherent external quantum efficiency of the one or more reference LEDs 10. When a plurality of reference LEDs 10 are used, the calculation unit 180 may derive an average value of the correction coefficients for the number of LEDs 10, calculated based on the individual pseudo-external quantum efficiency of each LED 10 and the inherent external quantum efficiency common to all LEDs 10, or may select a median value of the plurality of correction coefficients.

[0059] The test device 100 specifies the light emission wavelength related to the light emission of the test target LED 10 based on the excitation test of the test target LED 10 (step S107). Specifically, in a state where a plurality of test target LEDs 10 are arranged on the arrangement unit 110, the light emission control unit 160 of the test device 100 applies a current of a predetermined intensity to the plurality of test target LEDs 10 via the electrical connection unit 120, thereby illuminating these LEDs 10. The light measurement unit 170 receives the combined light emitted from the plurality of test target LEDs 10 via the optical system 140, measures the wavelength of the received combined light, and outputs a measurement result to the calculation unit 180.The calculation unit 180 specifies the wavelength of the combined light emitted by the plurality of test target LEDs 10 as the light emission wavelength concerning the light emission of the plurality of test target LEDs 10. The wavelength of the combined light may be, for example, the center wavelength of the combined light.

[0060] The test device 100 calculates the pseudo external quantum efficiency of the test target LED 10 based on the photoelectric conversion test of the test target LED 10 (step S109). Specifically, the light source 130 of the test device 100 irradiates a plurality of test target LEDs 10 with light of the irradiation intensity set in step S103 via the optical system 140. The electrical measurement unit 150, via the electrical connection unit 120, measures a photoelectric signal obtained by photoelectrically converting the light emitted from each of the plurality of test target LEDs 10 and outputs a measurement result to the calculation unit 180.The calculation unit 180 calculates the pseudo external quantum efficiency of each of the plurality of test target LEDs 10 based on the irradiation intensity of the light radiated from the light source 130 to the plurality of test target LEDs 10, the wavelength of the plurality of test target LEDs 10 measured in step S107 as the light emission wavelength concerning the light emission of the test target LEDs 10, and the measured photoelectric signal of each of the plurality of test target LEDs 10.

[0061] The test device 100 calculates the estimated value of the inherent external quantum efficiency from the pseudo-external quantum efficiency of the test target LED 10 using the correction coefficient (step S111). Specifically, the calculation unit 180 of the test device 100 uses the correction coefficient calculated in step S105 to calculate the estimated value of the inherent external quantum efficiency of each of the plurality of test target LEDs 10 from the pseudo-external quantum efficiency of the plurality of test target LEDs 10. For example, the calculation unit 180 calculates the inherent external quantum efficiency of each LED 10 by dividing the pseudo-external quantum efficiency of each LED 10 by the correction coefficient. The calculation unit 180 outputs a calculation result to the determination unit 190.

[0062] The test device 100 determines whether the test target LED 10 is defective based on the estimated value of the inherent external quantum efficiency (step S113), and the process ends. Specifically, the determination unit 190 of the test device 100 compares, for example, the inherent external quantum efficiency of each LED 10 input from the calculation unit 180 with the threshold value stored in the storage unit 200, and determines the LED 10 having an inherent external quantum efficiency lower than the threshold value as defective and excludes the LED 10 from the targets of the subsequent test.

[0063] In the test device 100, the order of each step in the operation sequence of Fig. 3 may be different and one or more steps may be omitted. For example, in the operational sequence of Fig. 3, the order of steps S101 and S103 may be reversed. Furthermore, steps S101 to S107 may be omitted, and in this case, the test device 100 may acquire in advance the correction coefficient calculated in step S105 and the light emission wavelength measured in step S107 regarding the light emission of the test target LED 10, and store the acquired correction coefficient and the light emission wavelength in the storage unit 200. Furthermore, the irradiance of the light source 130 may be measured in advance in steps S103 and S109, or it may be a setting value input to the light source 130.

[0064] As described above, according to the test apparatus 100 of the present embodiment, the test target LED 10 is irradiated with the light emitted from the light source 130, the photoelectric signal obtained by photoelectric conversion of the light emitted from the test target LED 10 is measured, and the pseudo external quantum efficiency having the correlation with the inherent external quantum efficiency of the test target LED 10 is calculated based on the irradiation intensity of the light emitted from the light source 130 to the test target LED 10, the emission wavelength related to the light emission of the test target LED 10, and the measured photoelectric signal of the test target LED 10.

[0065] As a comparison example with the test apparatus 100 according to the present embodiment, an apparatus is assumed that calculates the inherent external quantum efficiency by measuring a wavelength and light emission intensity of light emitted by applying a current of a predetermined intensity to a light-emitting element as a test target. For example, in a semiconductor test, a large number of light-emitting elements are arranged adjacently, and in a case where the semiconductor test is performed using the apparatus, when a large number of light-emitting elements are caused to emit light together, the light of the adjacent light-emitting elements is mixed, so the light emission intensity of each light-emitting element cannot be accurately measured.In order to avoid this, if the device causes a large number of light-emitting elements to emit light one after another, a lot of processing time is required to measure the light emission intensity of all the light-emitting elements and calculate the inherent external quantum efficiency.

[0066] On the other hand, according to the test apparatus 100 of the present embodiment, the pseudo-external quantum efficiency is calculated by measuring the photoelectric signal output by irradiating the test target light-emitting element with light at an irradiation intensity of a predetermined magnitude. Even when testing a semiconductor in which a large number of light-emitting elements are arranged side by side, the test apparatus 100 can simultaneously measure the photoelectric signal of each light-emitting element by irradiating the large number of light-emitting elements together with light, and calculate the pseudo-external quantum efficiency of each light-emitting element in parallel time.

[0067] Therefore, the test device 100 can also calculate, in parallel, an estimated value of the inherent external quantum efficiency that correlates with the pseudo-external quantum efficiency of each light-emitting element using the correction coefficient calculated in advance for the test target light-emitting element. Accordingly, the test device 100 can significantly shorten the processing time until the estimated value of the inherent external quantum efficiency of each light-emitting element is calculated, that is, the test execution time, compared to the device of the comparative example described above. Note that the test device 100 can also evaluate the light-emitting characteristics of each light-emitting element based on the pseudo-external quantum efficiency of each light-emitting element.

[0068] In the various embodiments described above, the light measuring unit 170 of the test apparatus 100 has been described as a structure in which the wavelength of the combined light is obtained by combining the light emitted from each of the plurality of test target LEDs 10, and the wavelength of the light emitted from the reference LED 10 is measured as the light emission wavelength of the plurality of test target LEDs 10. Furthermore, the calculation unit 180 of the test apparatus 100 has been described as a structure in which the pseudo external quantum efficiency of each of the plurality of test target LEDs 10 is calculated using the photoelectric signal of each of the plurality of test target LEDs 10 measured by the electrical measurement unit 150 and the wavelength of the combined light measured by the light measuring unit 170 or the wavelength of the reference LED 10.

[0069] Alternatively, the light measuring unit 170 of the test device 100 may not measure at least one of the wavelengths of the combined light obtained by combining the light emitted by each of the plurality of test target LEDs 10 or the wavelength of the reference LED 10. Alternatively, the test device 100 may not include the light measuring unit 170, and in this case, the optical system 140 may not include the bifurcated light guide 141.If the test device 100 does not measure the wavelength of the combined light of the plurality of test target LEDs 10 and the wavelength of the reference LED 10, the test device 100 may use a wavelength corresponding to the design value of the reference LED 10, a wavelength measured in advance through the light emission test of the reference LED 10, or a wavelength corresponding to the design value of one or more test target LEDs 10 as the light emission wavelength concerning the light emission of the one or more test target LEDs 10. Before calculating the pseudo-external quantum efficiency of the test target LED 10, the test device 100 may acquire data of these wavelengths from outside the test device 100, for example, through user input, and store the data in the storage unit 200.In this case, the calculation unit 180 of the test device 100 further calculates the pseudo external quantum efficiency of each of the one or more test target LEDs 10 using the photoelectric signal of each of the one or more test target LEDs 10 measured by the electrical measurement unit 150 and its wavelength.

[0070] In the various embodiments described above, the light measuring unit 170 of the test device 100 has been described as a structure in which the wavelength and light emission intensity of the light emitted by the reference LED 10 are measured to calculate the correction coefficient by the calculation unit 180. Furthermore, the calculation unit 180 of the test device 100 has been described as a structure in which the pseudo-external quantum efficiency of the reference LED 10 is calculated using the photoelectric signal of the reference LED 10 measured by the electrical measurement unit 150 and the wavelength of the reference LED 10 measured by the light measuring unit 170.The calculation unit 180 has been further described as a configuration in which the inherent external quantum efficiency of the reference LED 10 is calculated based on the wavelength and light emission intensity of the reference LED 10 measured by the light measuring unit 170 and the current supplied to the reference LED 10 by the light emission control unit 160. The calculation unit 180 has been further described as a configuration in which the correction coefficient is calculated by dividing the pseudo-external quantum efficiency of the reference LED 10 by the inherent external quantum efficiency of the reference LED 10.

[0071] Alternatively, the light measurement unit 170 of the test device 100 may not measure the wavelength of the light emitted by the reference LED 10, and the calculation unit 180 may obtain the correction coefficient corresponding to the test target LED 10, for example, from outside the test device 100 through a user input and store the correction coefficient in the storage unit 200 before calculating the estimated value of the inherent external quantum efficiency of the test target LED 10. In this case, the calculation unit 180 of the test device 100 further calculates the estimated value of the inherent external quantum efficiency of the test target LED 10 from the pseudo-external quantum efficiency calculated for the test target LED 10 by using the externally obtained correction coefficient.

[0072] In the various embodiments described above, the test device 100 may include another mechanism, such as a prism, in the optical system 140 instead of the branched light guide such as the bifurcated light guide 141. In this case, the prism or the like has a functional structure similar to the functional structure of the bifurcated light guide 141 described in the above embodiment.

[0073] In the above-described plurality of embodiments, when the LED group has a structure in which the plurality of LEDs are formed on a glass-based panel (PLP) having a substantially rectangular outer shape on which electric lines are formed, the electrical connection unit may have a structure in which the probe is brought into contact with each line in the row direction and the column direction arranged on two side surfaces of the panel.

[0074] Various embodiments of the present invention may be described with reference to flowcharts and block diagrams, whose blocks may represent (1) processing steps in which operations are performed, or (2) portions of devices responsible for performing operations. Certain steps and portions may be implemented by dedicated circuitry, programmable circuitry supplied with computer-readable instructions stored on computer-readable media, and / or processors supplied with computer-readable instructions stored on computer-readable media. Dedicated circuitry may include digital and / or analog hardware circuitry and may include integrated circuits (ICs) and / or discrete circuitry.The programmable circuit may include a reconfigurable hardware circuit including logical AND, logical OR, logical XOR, logical NAND, logical NOR and other logical operations, a memory element such as a flip-flop, a register, and a field programmable gate array (FPGA) and a programmable logic array (PLA), and the like.

[0075] A computer-readable medium may include any tangible device capable of storing instructions to be executed by a suitable device, and as a result, the computer-readable medium storing instructions includes an article of manufacture containing instructions that can be executed to produce means for performing operations specified in the flowcharts or block diagrams. Examples of the computer-readable medium may include an electronic storage medium, a magnetic storage medium, an optical storage medium, an electromagnetic storage medium, a semiconductor storage medium, and the like.More specific examples of the computer-readable medium may include a floppy disk (registered trademark), a floppy disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), electrically erasable programmable read-only memory (EEPROM), static random access memory (SRAM), compact disc read-only memory (CD-ROM), digital versatile disk (DVD), Blu-ray disk (registered trademark), memory stick, integrated circuit board, and the like.

[0076] The computer-readable instruction may comprise an assembly instruction, instruction set architecture (ISA) instruction, machine instruction, machine-dependent instruction, microcode, firmware instruction, state-determining data, or either source code or object code written in any combination of one or more programming languages, including an object-oriented programming language such as Smalltalk (registered trademark), JAVA (registered trademark), C++, or the like, and a conventional procedural programming language such as a "C" programming language or similar programming language.

[0077] The computer-readable instruction may be provided to a processor or programmable circuit of a programmable data processing device, such as a computer, locally or over a local area network (LAN), a wide area network (WAN), such as the Internet, or the like, to execute the computer-readable instruction to produce means for performing the operations specified in the flowcharts or block diagrams. The computer may be a personal computer (PC), a tablet computer, a smartphone, a workstation, a server computer, or a computer such as a general-purpose computer or a special-purpose computer, or a computer system to which a plurality of computers are connected. Such a computer system to which a plurality of computers are connected is also called a distributed computer system and is, in the broadest sense, a computer.In a distributed computer system, a plurality of computers jointly execute a program, with each of the plurality of computers executing a portion of the program and passing data between the computers as needed during the execution of the program.

[0078] Examples of the processor are a computer processor, a central processing unit (CPU), a processing unit, a microprocessor, a digital signal processor, a controller, and a microcontroller. The computer may comprise one processor or a plurality of processors. In a multiprocessor system with a plurality of processors, the plurality of processors jointly execute a program, with each of the processors executing a portion of the program and passing data between the computers as needed during the execution of the program. For example, when executing a plurality of tasks, each of the plurality of processors may execute a portion of each task piece by piece by performing a task switch for each time period. In this case, which portion of a program each processor is responsible for executing changes dynamically.In addition, multiprocessor-aware programming can statically determine which part of the program each of the multiple processors is responsible for execution.

[0079] Fig.4 shows an example of a computer 1200 in which a variety of aspects of the present invention may be embodied in whole or in part. A program installed on the computer 1200 may cause the computer 1200 to function as an operation associated with a device according to embodiments of the present invention, or as one or more "units" of the device, or to perform the operation of the one or more "units," and / or may cause the computer 1200 to perform processes according to embodiments of the present invention or steps of the processes. Such a program may be executed by a CPU 1212 to cause the computer 1200 to perform certain operations associated with some or all of the blocks in the flowcharts or block diagrams described herein.

[0080] The computer 1200 according to the present embodiment includes a CPU 1212, a RAM 1214, a graphics controller 1216, and a display device 1218, which are connected to each other via a host controller 1210. The computer 1200 also includes input / output units such as a communication interface 1222, a hard disk drive 1224, a DVD-ROM drive 1226, and an IC card drive, which are connected to the host controller 1210 via an input / output controller 1220. The computer also has legacy input / output units such as a ROM 1230 and a keyboard 1242, which are connected to the input / output controller 1220 via an input / output chip 1240.

[0081] The CPU 1212 operates according to the programs stored in the ROM 1230 and the RAM 1214 and controls each unit accordingly. The graphics controller 1216 captures image data generated by the CPU 1212 into a frame buffer or the like provided in the RAM 1214 or in the graphics controller 1216 itself and displays the image data on the display device 1218.

[0082] The communication interface 1222 communicates with other electronic devices over a network. The hard disk drive 1224 stores programs and data to be used by the CPU 1212 in the computer 1200. The DVD-ROM drive 1226 reads programs or data from the DVD-ROM 1201 and provides the programs or data to the hard disk drive 1224 via the RAM 1214. The IC card drive reads programs and data from an IC card and / or writes programs and data to the IC card.

[0083] ROM 1230 stores a boot program or the like to be executed by computer 1200 at the time of activation, and / or a program that depends on the hardware of computer 1200. Input / output chip 1240 can also connect various input / output devices to input / output controller 1220 via a parallel port, a serial port, a keyboard port, a mouse port, or the like.

[0084] A program is provided from a computer-readable storage medium such as the DVD-ROM 1201 or an IC card. The program is read from the computer-readable storage medium, installed on the hard disk drive 1224, the RAM 1214, or the ROM 1230, which are also examples of a computer-readable storage medium, and executed by the CPU 1212. Information processing written in this program is read by the computer 1200 and provides cooperation between the programs and the various types of hardware resources described above. An apparatus or method can be constituted by implementing the operation or processing of information according to the use of the computer 1200.

[0085] For example, when performing communication between the computer 1200 and external devices, the CPU 1212 may execute a communication program loaded into the RAM 1214 and instruct the communication interface 1222 to perform communication processing based on the processing described in the communication program. Under the control of the CPU 1212, the communication interface 1222 reads transmission data stored in a transmission buffer area provided in a recording medium such as the RAM 1214, the hard disk drive 1224, the DVD-ROM 1201, or an IC card, and sends the read transmission data to the network or writes reception data received from the network into a reception buffer area or the like provided in the recording medium.

[0086] The CPU 1212 can also store all or required portions of the files or databases on an external recording medium such as the hard disk drive 1224, the DVD-ROM drive 1226 (DVD-ROM 1201), or an IC card. The data is read by the RAM 1214, and various processing is performed on the data in the RAM 1214. The CPU 1212 can then write the processed data back to the external recording medium.

[0087] Various types of information, such as various types of programs, data, tables, and databases, may be stored in the recording medium for information processing. The CPU 1212 may perform various types of processing on the data read from the RAM 1214, including various types of operations, information processing, conditional judgment, conditional branching, unconditional branching, information retrieval / replacement, or the like described throughout this disclosure and specified by an instruction sequence of a program, to write the results back to the RAM 1214. In addition, the CPU 1212 may retrieve information in a file, a database, or the like on the recording medium.For example, if a plurality of entries, each having an attribute value of a first attribute linked to an attribute value of a second attribute, are stored on the recording medium, the CPU 1212 may search the plurality of entries for an entry whose attribute value of the first attribute matches a specified condition, read the attribute value of the second attribute stored in the entry, and thereby acquire the attribute value of the second attribute linked to the first attribute that satisfies a predetermined condition.

[0088] The programs or software modules in the above description may be stored on the computer 1200 or a computer-readable storage medium near the computer 1200. Furthermore, a recording medium such as a hard disk or RAM provided in a server system connected to a dedicated communication network or the Internet may be used as a computer-readable storage medium, thereby providing a program to the computer 1200 via the network.

[0089] Although the present invention has been described with reference to the embodiments, the technical scope of the present invention is not limited to the above-described embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above-described embodiments. It is also clear from the scope of the claims that the embodiments supplemented by such modifications or improvements can be incorporated into the technical scope of the present invention.

[0090] It should be noted that the operations, procedures, steps, and stages of each process performed by a device, system, program, and method shown in the claims, embodiments, or diagrams may be performed in any order, as long as the order is not specified by "before," "before," or the like, and as long as the output of a previous process is not used in a subsequent process. Even if the process flow is described in the claims, embodiments, or drawings using terms such as "first" or "next," this does not necessarily mean that the process must be performed in that order. EXPLANATION OF REFERENCE SYMBOLS 10 LED 11 Terminal 15 waffles 100 test devices 110 arrangement unit 111 Through hole 120 Electrical connection unit 121 Substrat 123 probe 130 light source 140 optical system 150 Unit for electrical measurement 160 Light emission control unit 170 light measuring unit 180 calculation unit 190 Determination unit 200 storage units 210 Shielding unit 1200 computers 1201 DVD-ROM 1210 Host Controller 1212 CPU 1214 RAM 1216 graphics controller 1218 display device 1220 input / output controller 1222 Communication interface 1224 hard disk drive 1226 DVD-ROM drive 1230 ROM 1240 input / output chip 1242 keyboard

Claims

[1] Test device, comprising: a light source, an electrical measurement unit that measures a photoelectric signal obtained from a light-emitting test target element that photoelectrically converts light emitted by the light source, and a calculation unit that calculates a pseudo external quantum efficiency that has a correlation with the inherent external quantum efficiency of the test target light-emitting element, based on the irradiation intensity of the light radiated from the light source to the test target light-emitting element, a light emission wavelength related to the light emission of the test target light-emitting element, and the photoelectric signal measured from the test target light-emitting element. [2] The test device according to claim 1, wherein the calculation unit calculates an estimated value of the inherent external quantum efficiency of the test target light-emitting element obtained from a light emission test from the pseudo-external quantum efficiency of the test target light-emitting element using a correction coefficient based on the pseudo-external quantum efficiency calculated in advance for a reference light-emitting element and the inherent external quantum efficiency calculated in advance for a light emission test of the reference light-emitting element. [3] The test device according to claim 2, wherein the reference light-emitting element is an ideal light-emitting element corresponding to a design value of the test target light-emitting element, or a light-emitting element included in the same production batch as the test target light-emitting element and satisfying a predetermined acceptance reference. [4] The test device according to claim 2, wherein the light emission wavelength concerning the light emission of the test target light-emitting element is a wavelength corresponding to a design value of the reference light-emitting element, a wavelength measured in advance by the light emission test of the reference light-emitting element, or a wavelength in accordance with a design value of the test target light-emitting element. [5] Test device according to claim 2, further comprising: a light emission control unit that causes the reference light emission element to emit light, and a light measuring unit which measures the wavelength and the light emission intensity of the light emitted by the light-emitting reference element, where the calculation unit the pseudo-external quantum efficiency of the reference light-emitting element is calculated based on the radiation intensity of the light emitted from the light source onto the reference light-emitting element, the wavelength of the reference light-emitting element measured as the light emission wavelength relating to the light emission of the test target light-emitting element, and the measured photoelectric signal of the reference light-emitting element, the inherent external quantum efficiency of the reference light-emitting element is calculated based on the wavelength and the light emission intensity measured by the reference light-emitting element and the current applied by the light emission control unit to the reference light-emitting element, and the correction coefficient is calculated by dividing the pseudo-external quantum yield by the inherent external quantum yield. [6] Test device according to claim 5, further comprising: an optical system that irradiates the reference light-emitting element with light incident in one direction from the light source and irradiates the light measuring unit with light incident in another direction from the reference light-emitting element. [7] Test device according to one of claims 1 to 6, wherein the electrical measurement unit measures the photoelectric signal obtained from each of a plurality of test target light-emitting elements that jointly photoelectrically convert light emitted by the light source, and the calculation unit calculates the pseudo external quantum efficiency of each of the plurality of test target light-emitting elements based on the radiation intensity of the light emitted from the light source to the plurality of test target light-emitting elements, the light emission wavelength relating to the light emission of the plurality of test target light-emitting elements, and the photoelectric signal measured for each of the plurality of test target light-emitting elements. [8] The test apparatus according to claim 7, wherein the calculation unit calculates an estimated value of the inherent external quantum efficiency of each of the plurality of test target light-emitting elements obtained from a light emission test from the pseudo-external quantum efficiency of each of the plurality of test target light-emitting elements by using a correction coefficient based on the pseudo-external quantum efficiency calculated in advance for a reference light-emitting element and the inherent external quantum efficiency calculated in advance for a light emission test of the reference light-emitting element. [9] The test apparatus according to claim 8, wherein the calculation unit uses the correction coefficient that varies depending on a production batch including the plurality of test target light-emitting elements. [10] The test apparatus according to claim 8, further comprising a determination unit that determines the quality of each of the plurality of test target light-emitting elements based on the estimated value of the inherent external quantum efficiency of each of the plurality of test target light-emitting elements. [11] Test device according to claim 7, further comprising: a light emission control unit which causes the plurality of light-emitting test target elements to emit light together, a light measuring unit that measures, as the light emission wavelength concerning the light emission of the plurality of light-emitting test target elements, a wavelength of the combined light obtained by combining the light emitted from each of the plurality of light-emitting test target elements, and an optical system that irradiates the plurality of test target light-emitting elements with light incident from the light source in one direction, and irradiates the light measuring unit with combined light obtained by combining the light incident from each of the plurality of test target light-emitting elements in a different direction. [12] Test procedures, including: Illuminating a light-emitting test target element with light emitted by a light source, Measuring a photoelectric signal obtained by the light-emitting test target element that photoelectrically converts emitted light, and Calculating a pseudo-external quantum efficiency that has a correlation with the inherent external quantum efficiency of the test target light-emitting element based on the irradiation intensity of the light emitted from the light source to the test target light-emitting element, a light emission wavelength related to the light emission of the test target light-emitting element, and the measured photoelectric signal of the test target light-emitting element. [13] Program for causing a test device testing a light-emitting element to perform the following: Illuminating a light-emitting test target element with light emitted by a light source, Measuring a photoelectric signal obtained from the test target light-emitting element that photoelectrically converts emitted light, and calculating a pseudo-external quantum efficiency that has a correlation with the inherent external quantum efficiency of the test target light-emitting element based on the irradiation intensity of the light emitted from the light source to the test target light-emitting element, a light emission wavelength related to the light emission of the test target light-emitting element, and the measured photoelectric signal of the test target light-emitting element.

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