Test apparatus, test method, and computer readable storage medium

Abstract

The invention provides a test device. The test device comprises a light source; an electrical measurement unit that measures a photoelectric signal obtained by photoelectrically converting the light emitted from the light source by the light-emitting element to be tested; and a calculation unit that calculates a light emission wavelength related to the light emission of the light-emitting element to be tested on the basis of the irradiation intensity of the light irradiated from the light source to the light-emitting element to be tested, the light emission wavelength related to the light emission of the light-emitting element to be tested, and the measured photoelectric signal of the light-emitting element to be tested. A pseudo external quantum efficiency associated with the original external quantum efficiency of the light-emitting element to be tested is calculated. The calculation unit may use a correction coefficient based on a pseudo external quantum efficiency calculated in advance for the reference light-emitting element and an original external quantum efficiency calculated in advance by a light emission test for the reference light-emitting element, to calculate the pseudo external quantum efficiency of the light-emitting element to be tested on the basis of the pseudo external quantum efficiency of the light-emitting element to be tested. An estimated value of the original external quantum efficiency obtained by the light emission test of the light-emitting element to be tested is calculated.

Description

Technical Field

[0001] The invention relates to a test device, a test method and a computer-readable storage medium. Background Art

[0002] Patent Document 1 states that “Characterization of a solar cell is performed as follows. External quantum efficiency (EQE) is estimated using cell responses at different wavelengths (measured using a white light halogen lamp combined with a bandpass filter)” (

[0121] ). [Prior art literature] [Patent Document] [Patent Document 1] Japanese Patent Application Publication No. 2021-9950 Summary of the invention

[0003] In a first aspect of the present invention, a test device is provided. The test device includes: a light source; an electrical measuring unit that measures a photoelectric signal obtained by photoelectrically converting light irradiated from the light source by a light-emitting element as a test object; and a calculating unit that calculates a pseudo external quantum efficiency correlated with the original external quantum efficiency of the light-emitting element as a test object based on the irradiation intensity of the light irradiated from the light source to the light-emitting element as a test object, a light emission wavelength related to the light emission of the light-emitting element as a test object, and the measured photoelectric signal of the light-emitting element as a test object.

[0004] In the test device, the calculation unit may also use a correction coefficient based on the pseudo external quantum efficiency calculated in advance for the benchmark light-emitting element and the original external quantum efficiency calculated in advance for the benchmark light-emitting element from the light-emitting test, and calculate an estimated value of the original external quantum efficiency of the light-emitting element that is the test object obtained from the light-emitting test based on the pseudo external quantum efficiency of the light-emitting element that is the test object.

[0005] In any of the test devices, the reference light-emitting element may be an ideal light-emitting element based on the design value of the test object light-emitting element, or a light-emitting element that meets a predetermined qualified standard and is included in the same manufacturing batch as the test object light-emitting element.

[0006] In any of the test devices, the emission wavelength related to the emission of the light-emitting element serving as the test object may be a wavelength based on a design value of the light-emitting element serving as the reference, a wavelength of the light-emitting element serving as the reference measured in advance by the emission test, or a wavelength based on a design value of the light-emitting element serving as the test object.

[0007] Any of the test devices may further include a light emission control unit that causes the reference light emitting element to emit light. Any of the test devices may further include a light measuring unit that measures the wavelength and light emission intensity of the light from the reference light emitting element. In any of the test devices, the calculation unit may calculate the pseudo external quantum efficiency of the reference light emitting element based on the irradiation intensity of the light irradiated 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 light emitting element to be tested, and the photoelectric signal measured by the reference light emitting element. In any of the test devices, the calculation unit may calculate the original external quantum efficiency of the reference light emitting element based on the measured wavelength and light emission intensity of the reference light emitting element and the current input to the reference light emitting element by the light emission control unit. In any of the test devices, the calculation unit may calculate the correction coefficient by dividing the pseudo external quantum efficiency by the original external quantum efficiency.

[0008] Any of the test devices may further include an optical system that irradiates light from the light source incident in one direction toward the reference light emitting element and irradiates light from the reference light emitting element incident in another direction toward the light measuring unit.

[0009] In any of the test devices, the electrical measurement unit may measure the photoelectric signal obtained by photoelectrically converting the light irradiated from the light source to each of the plurality of light emitting elements as test objects. In any of the test devices, the calculation unit may calculate the pseudo external quantum efficiency of each of the plurality of light emitting elements as test objects based on the irradiation intensity of the light irradiated from the light source to the plurality of light emitting elements as test objects, the emission wavelength associated with the emission of the plurality of light emitting elements as test objects, and the photoelectric signal measured for each of the plurality of light emitting elements as test objects.

[0010] In any of the test devices, the calculation unit may also use a correction coefficient based on the pseudo external quantum efficiency calculated in advance for the benchmark light-emitting element and the original external quantum efficiency calculated in advance for the benchmark light-emitting element from the light-emitting test, and calculate the estimated value of the original external quantum efficiency of each of the multiple light-emitting elements that are the test objects obtained from the light-emitting test based on the pseudo external quantum efficiency of each of the multiple light-emitting elements that are the test objects.

[0011] In any of the test devices, the calculation unit may use the correction coefficient that differs according to a manufacturing lot including the plurality of light emitting elements to be tested.

[0012] Any of the test devices may further include a determination unit that determines whether each of the plurality of light-emitting elements to be tested is good or not based on an estimated value of the original external quantum efficiency of each of the plurality of light-emitting elements to be tested.

[0013] Any of the test devices may also include a light control unit that causes the plurality of light emitting elements to be tested to emit light together. Any of the test devices may also include a light measuring unit that measures a wavelength of a synthesized light synthesized from the light from each of the plurality of light emitting elements to be tested as the light emission wavelength associated with the light emission of the plurality of light emitting elements to be tested. Any of the test devices may also include an optical system that irradiates the plurality of light emitting elements to be tested with light from the light source incident in one direction, and irradiates the light measuring unit with synthesized light synthesized from the light from each of the plurality of light emitting elements to be tested incident in another direction.

[0014] In a second aspect of the present invention, a test method is provided. The test method comprises, in any of the test devices, irradiating light from a light source to a light-emitting element to be tested; measuring a photoelectric signal obtained by photoelectric conversion of the irradiated light by the light-emitting element to be tested; and calculating a pseudo external quantum efficiency correlated with the original external quantum efficiency of the light-emitting element to be tested based on the irradiation intensity of the light irradiated from the light source to the light-emitting element to be tested, a light emission wavelength related to the light emission of the light-emitting element to be tested, and the measured photoelectric signal of the light-emitting element to be tested.

[0015] In a second aspect of the present invention, a program is provided. The program causes a test device for testing a light-emitting element to execute the following sequence: irradiating light from a light source to a light-emitting element to be tested; measuring a photoelectric signal obtained by photoelectric conversion of the irradiated light by the light-emitting element to be tested; and calculating a pseudo external quantum efficiency associated with the original external quantum efficiency of the light-emitting element to be tested based on the irradiation intensity of the light irradiated from the light source to the light-emitting element to be tested, a light emission wavelength associated with the light emission of the light-emitting element to be tested, and the measured photoelectric signal of the light-emitting element to be tested.

[0016] In addition, the above summary of the invention does not list all the features of the present invention. In addition, sub-combinations of these feature groups may also constitute inventions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 1 is an example of a schematic overall view showing a test device 100 for testing a plurality of LEDs (Light Emitting Diodes) 10 . Figure 2 1 is an example of a schematic overall view showing a test device 100 for testing a plurality of LEDs 10 . Figure 3 This is an example of a flowchart for explaining the flow of a testing method of the testing apparatus 100 . Figure 4 This diagram shows an example of a computer 1200 that can implement all or part of various aspects of the present invention. DETAILED DESCRIPTION

[0018] The present invention will be described below by way of the embodiments of the invention, but the following embodiments do not limit the invention of the scope of the claims. In addition, not all combinations of features described in the embodiments are essential to the solution means of the invention.

[0019] Figure 1 and Figure 2 FIG. 1 is an example of a schematic overall diagram showing a test device 100 for testing a plurality of LEDs 10. Figure 1 and Figure 2 In FIG. 1 , mutually orthogonal X-axis, Y-axis, and Z-axis are shown. The right direction toward the paper is set as the positive direction of the X-axis, the upward direction toward the paper is set as the positive direction of the Z-axis, and the depth direction toward the paper is set as the positive direction of the Y-axis.

[0020] The test device 100 uses the photoelectric effect of the light-emitting element to calculate the pseudo external quantum efficiency associated with the original external quantum efficiency of the light-emitting element based on the photoelectric signal output from the light-emitting element irradiated with light. The test device 100 of this embodiment calculates the pseudo external quantum efficiency of each LED 10 based on the photoelectric signal output from each LED 10 by irradiating light uniformly to an LED group formed by forming a plurality of LEDs 10 on a wafer 15 as an LED wafer. The test device 100 of this embodiment further calculates the estimated value of the original external quantum efficiency of each LED 10 based on the pseudo external quantum efficiency of each LED 10. The test device 100 of this embodiment tests the optical characteristics of the LED 10 by calculating the external quantum efficiency of the LED 10 in this way.

[0021] In this embodiment, LED 10 is a micro LED with a size of 100 μm or less. In addition, LED 10 may be a small LED with a size greater than 100 μm and less than 200 μm, or an LED with a size greater than 200 μm, instead of a micro LED, or may be other light-emitting elements such as LD (Laser Diode). These are all examples of light-emitting elements that are test objects and light-emitting elements that are references.

[0022] In the present embodiment, the plurality of LEDs 10 are not electrically connected to each other on the wafer 15. The LED group is a back-lighting type in which the light-emitting surfaces of the plurality of LEDs 10 face the wafer 15, and the wafer 15 allows light to pass through. On each LED 10, two terminals 11 are formed apart from each other in the Y-axis direction. Each terminal 11 of the plurality of LEDs 10 does not face the wafer 15. In addition, with respect to a back-lighting type LED group like the present embodiment, the plurality of LEDs 10 and the wafer 15 on which the plurality of LEDs 10 are mounted are sometimes collectively referred to as a wafer. In addition, the LED group may also be a surface-lighting type in which the light-emitting surfaces of the plurality of LEDs 10 do not face the wafer 15. In this case, the wafer 15 may not allow light to pass through. In addition, each terminal 11 of the plurality of LEDs 10 may not face the wafer 15 or may face the wafer 15. In the case in which each terminal 11 of the plurality of LEDs 10 faces the wafer 15, a through hole extending in the Z-axis direction is formed at the position of each terminal 11 in the wafer 15 so that a probe for power supply contacts each terminal 11.

[0023] Alternatively, a plurality of LEDs 10 may be formed on a wafer provided with electric wiring or a panel (PLP) of a glass substrate having a substantially square shape, and may be electrically connected to each other to form a module or a unit.

[0024] As an example, the test device 100 of the present embodiment includes a placement 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. Figure 1 and Figure 2 In FIG. 1 , black arrows are used to indicate the flow of signals between the components.

[0025] The mounting portion 110 mounts the LED group on the positive side of the Z axis. The mounting portion 110 mounts the LED group including the plurality of LEDs 10 to be tested. The mounting portion 110 may further directly mount one or more single-chip LEDs 10 to be a reference, or may mount the LED group including one or more LEDs 10 to be a reference.

[0026] The carrier portion 110 in the illustrated example has a generally circular shape when viewed from above in the Z-axis direction, but may also have other shapes. The carrier portion 110 has a holding function such as a vacuum chuck or an electrostatic chuck to hold the wafer 15 of the LED group being carried. The carrier portion 110 has a through hole 111, for example, in the center of the XY plane so as not to block light from the light source 130 that passes through the wafer 15 and irradiates the plurality of LEDs 10, or light that is emitted by the plurality of LEDs 10 and passes through the wafer 15. The carrier portion 110 holds the wafer 15 around the through hole 111. In addition, Figure 1 and Figure 2 The through hole 111 is indicated by a dotted line.

[0027] The electrical connection portion 120 is, for example, a probe card (probe substrate), and is electrically connected to the terminals 11 of each of the plurality of LEDs 10 included in the LED group of the test object. The electrical connection portion 120 of the present embodiment is further electrically connected to the terminals 11 of one or more monolithic LEDs 10 serving as a reference, or the terminals 11 of an LED group including one or more LEDs 10 serving as a reference.

[0028] The electrical connection portion 120 includes a substrate 121 and a plurality of probes 123. A 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 one main surface of the substrate 121. The plurality of probes 123 can contact the terminals 11 of the respective LEDs 10 when the substrate 121 faces the LED group on the mounting portion 110.

[0029] The electrical connection portion 120 moves two-dimensionally in the XY plane and rises and falls in the Z-axis direction. Figure 1 and Figure 2 , a hollow arrow indicates the moving direction of the electrical connection portion 120. The electrical connection portion 120 is moved, for example, in such a manner that the plurality of LEDs 10 are located between the electrical connection portion 120 and the light source 130, so that the plurality of probes 123 contact the respective terminals 11 of the plurality of LEDs 10 from the positive direction side of the Z axis of the wafer 15. The other end of each probe 123, which is opposite to the end in contact with the terminal 11, is electrically connected to an electrical wiring provided on the substrate 121. The electrical wiring of each probe 123 extends from the side surface of the substrate 121 and is electrically connected to the electrical measurement portion 150 and the light emission control portion 160.

[0030] The light source 130 irradiates light to one or more LEDs 10. In this embodiment, the light source 130 is as follows: Figure 1 As shown, light is irradiated to one or more LEDs 10 via the optical system 140. Figure 1 In FIG. 1 , light from the light source 130 is represented by oblique lines.

[0031] As an example, the light source 130 is a white light source or a light source that emits light of a specific wavelength. In the case of using the light source 130 as a white light source, a filter that filters light in the infrared region may also be arranged between the light source 130 and the LED 10 to prevent the LED 10 from becoming hot. In the case of using the light source 130 that emits light of a specific wavelength, the light source 130 may also be set to emit light of the reaction wavelength of the LED 10, that is, light of the wavelength at which the LED 10 can output a photoelectric signal. As an example, in the case where the design values ​​of the emission wavelength and the reaction wavelength of the LED 10 are 446nm and 560nm, the light source 130 may also be set to emit light in a band of 560nm±several nm. In the case of using the light source 130 that emits light of the reaction wavelength of the LED 10, the energy efficiency is improved compared to the white light source by not emitting the amount of light of wavelengths other than the reaction wavelength of the LED 10. In this case, for example, a filter that filters light in the infrared region as a band other than the reaction wavelength of the LED 10 may not be required.

[0032] The light source 130 may also be a surface light source that can evenly irradiate light toward a plane where the irradiation object is located. 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 mounting portion 110 can be calculated in advance by calculating the irradiation intensity per unit area (mW / cm 2 ]) multiplied by the area of ​​each LED 10 ([cm 2 ]) and is calculated and stored in the storage unit 200. Alternatively, the light source 130 may also emit light having an illuminance distribution within the plane. In this case, the illuminance distribution may also be measured in advance and stored in the storage unit 200. For example, the irradiation intensity of the light irradiated from the light source 130 to each position of the plurality of LEDs 10 on the mounting portion 110 may also be measured in advance and stored in the storage unit 200, and the calculation of the external quantum efficiency may also be applied to the irradiation intensity of each position. In addition, the irradiation intensity of the light irradiated from the light source 130 to each of the plurality of LEDs 10 refers to the irradiation intensity of the light of the reaction wavelength of LED 10 in the light from the light source 130. For example, in the case where the light source 130 is a white light source, the irradiation intensity of the light of the reaction wavelength of LED 10 may be calculated by multiplying the irradiation intensity of the light of all wavelength bands from the light source 130 by the ratio of the relative intensity of the reaction wavelength of LED 10 when the total intensity of all wavelength bands is set to 1. In addition, the light source 130 may also be able to adjust the irradiation time, wavelength, intensity, etc. of the light irradiated to the object.

[0033] The optical system 140 irradiates the light incident from the light source 130 to one or more LEDs 10. Figure 1 and Figure 2As shown, the optical system 140 of this embodiment is configured such that one side is connected to the light source 130 and the light measuring unit 170, and the other side is directed toward the LED group on the mounting unit 110. In this embodiment, the optical system 140 is an optical element group common to the light source 130 and the light measuring unit 170. The optical system 140 can perform photoelectric signal measurement and wavelength measurement of the LED 10 using a bidirectional optical path. Specifically, the optical system 140 irradiates the light from the light source 130 incident in one direction to the LED 10, and irradiates the light from the LED 10 incident in the other direction to the light measuring unit 170.

[0034] More specifically, if Figure 1 As shown, the optical system 140 of this embodiment diffuses the light from the light source 130 and irradiates the light from the light source 130 to the plurality of LEDs 10. That is, the projection surface of the light from the light source 130 radiated via the optical system 140 on the XY plane on the mounting portion 110 covers at least the plurality of LEDs 10 of the LED group.

[0035] The optical system 140 of this embodiment further emits the synthesized light obtained by synthesizing the lights from the plurality of LEDs 10 to the light measuring unit 170. Figure 2 In FIG. 1 , the composite light from a plurality of LEDs 10 is represented by oblique lines. Figure 2 As shown, the optical system 140 collects diffused light from a plurality of LEDs 10 and guides the diffused light to the light measuring unit 170. Figure 2 As shown, the optical system 140 of this embodiment guides the light from the plurality of LEDs 10 to both the light source 130 and the light measuring unit 170 . However, the optical system 140 may alternatively be configured to guide the light 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 of the present embodiment has a 2-branch fiber 141. The 2-branch fiber 141 is a Y-shaped optical fiber. The end of the branch side of the 2-branch fiber 141 is connected to the light source 130 and the light measuring unit 170. The optical system 140 may also have a multi-branch fiber such as a 3-branch fiber or a 4-branch fiber instead of the 2-branch fiber 141. In this case, the test device 100 may also have more than two light sources 130, or one light source 130 may be connected to each end of the branch side of the multi-branch fiber. In this case, the optical system 140 may also collect light from multiple light sources 130 that radiate light of different wavelength bands and irradiate it to multiple LEDs 10. For example, the optical system 140 may also collect light from three light sources 130 that respectively radiate light of each reaction wavelength of RGB of LED 10 and irradiate it to LED 10. When the light source 130 radiates light of a specific wavelength band, by connecting the plurality of light sources 130 to the optical system 140 in this way, the wavelength band width of the light irradiated to the LED 10 can be expanded, and more specifically, the LED 10 can be photoelectrically converted.

[0037] In addition, the optical system 140 may further include a lens assembly 143 including one or more lenses, and the lens assembly 143 is arranged on the optical path in the optical system 140. Figure 2 As shown, the lens assembly 143 converges diffused light emitted from the plurality of LEDs 10 and allows the converged light to enter the two-branch fiber 141 .

[0038] The test device 100 can utilize the mutually connected configuration of the optical system 140, the light source 130, and the light measuring unit 170 to bidirectionally perform photoelectric signal measurement and wavelength measurement of a plurality of LEDs 10 using the common optical system 140. When the test device 100 ends one of the photoelectric signal measurement and the wavelength measurement and starts the other, it is not necessary to change the device configuration or move the LED 10.

[0039] The electrical measuring unit 150 measures a photoelectric signal obtained by photoelectrically converting light irradiated from the light source 130 by the LED 10 serving as the test object. The electrical measuring unit 150 of this embodiment measures a photoelectric signal obtained by photoelectrically converting light irradiated from the light source 130 by each of the plurality of LEDs 10 serving as the test object. The electrical measuring unit 150 of this embodiment also measures a photoelectric signal obtained by photoelectrically converting light irradiated from the light source 130 by one or more LEDs 10 serving as the reference.

[0040] More specifically, the electrical measuring unit 150 measures the current value of the current output from each LED 10 via the electrical connecting unit 120. The electrical measuring unit 150 outputs the current value measured for each LED 10 to the calculating unit 180. In addition, the electrical measuring unit 150 may measure a voltage value corresponding to the current value instead of the current value of the current output from the LED 10.

[0041] The light control unit 160 supplies a current or voltage of a predetermined magnitude to the LED 10 to make the LED 10 emit light. The light control unit 160 of this embodiment supplies a current or voltage of a predetermined magnitude to the multiple LEDs 10 that are the test objects through the electrical connection unit 120 to make the multiple LEDs 10 that are the test objects emit light together. The light control unit 160 of this embodiment further makes one or more LEDs 10 that are the reference emit light.

[0042] The light measuring unit 170 measures the wavelength of light from the LED 10. The light measuring unit 170 of the present embodiment measures the wavelength of synthesized light obtained by synthesizing the light from each of the plurality of LEDs 10 received via the optical system 140. The synthesized light obtained by synthesizing the light from each of the plurality of LEDs 10 is an example of a light emission wavelength related to the light emission of the plurality of LEDs 10 that are test subjects. The light measuring unit 170 may also measure the wavelength of light that causes one or more LEDs 10 in a group to emit light according to each group, wherein all the LEDs 10 that are test subjects are divided into several groups. In addition, the light measuring unit 170 may also individually measure the wavelength of light from each of the plurality of LEDs 10 that are test subjects. The light measuring unit 170 of the present embodiment further measures the wavelength and light emission intensity of light from one or more LEDs 10 that are references.

[0043] The light measuring unit 170 of this embodiment includes, for example, a wavelength meter. The light measuring unit 170 may also measure the wavelength of the synthesized light from the plurality of LEDs 10 and identify the intensity distribution of the wavelength of the synthesized light. The light measuring unit 170 may identify the peak wavelength or half-width of the synthesized light based on the intensity distribution of the synthesized light, and may also measure the wavelength corresponding to the color when the synthesized light is visually observed, that is, the main wavelength. The light measuring unit 170 may also include a spectrometer or a spectrum analyzer, etc., instead of the wavelength meter. The light measuring unit 170 outputs the measured wavelength or luminous intensity to the calculation unit 180.

[0044] The calculation unit 180 calculates a pseudo external quantum efficiency associated with the original external quantum efficiency of the LED 10 to be tested. More specifically, the calculation unit 180 calculates the pseudo external quantum efficiency based on the intensity of the irradiation from the light source 130 to the LED 10 to be tested, the wavelength of the light emission associated with the light emission of the LED 10 to be tested, and the photoelectric signal measured by the LED 10 to be tested. The calculation unit 180 further calculates an estimated value of the original external quantum efficiency of the LED 10 to be tested obtained from the light emission test based on the pseudo external quantum efficiency of the LED 10 to be tested.

[0045] The calculation unit 180 of the present embodiment calculates the pseudo external quantum efficiency of each of the plurality of LEDs 10 that are the test objects. More specifically, the calculation unit 180 calculates the pseudo external quantum efficiency of each of the plurality of LEDs 10 that are the test objects based on the irradiation intensity from the light source 130 to the plurality of LEDs 10 that are the test objects, the emission wavelength related to the emission of the plurality of LEDs 10 that are the test objects, and the photoelectric signal measured for each of the plurality of LEDs 10 that are the test objects. The calculation unit 180 further calculates the estimated value of the original external quantum efficiency of each of the plurality of LEDs 10 that are the test objects obtained from the emission test based on the pseudo external quantum efficiency of the plurality of LEDs 10 that are the test objects.

[0046] The calculation unit 180 may obtain data of the irradiation intensity of the one or more LEDs 10 to be tested from the light source 130 from the outside of the test device 100 through user input, and store the data in the storage unit 200. The irradiation intensity of the one or more LEDs 10 to be tested from the light source 130 may be the irradiation intensity measured by placing the light measuring unit 170 on the mounting unit 110 instead of the LED group in the test device 100.

[0047] The calculation unit 180 uses, for example, the wavelength of the synthesized light of the plurality of LEDs 10 input from the light measuring unit 170 as the emission wavelength related to the emission of the plurality of LEDs 10 to be tested. Alternatively, the calculation unit 180 may use the wavelength of the reference LED 10 input from the light measuring unit 170 as the emission wavelength related to the emission of one or more LEDs 10 to be tested.

[0048] The LED 10 used as the reference may also be an LED 10 that can be compared with the LED 10 used as the test object and that exhibits good light-emitting characteristics. The LED 10 used as the reference may be, for example, an ideal light-emitting element based on the design value of the LED 10 used as the test object, or may be an LED 10 that meets a predetermined qualified standard and is included in the same manufacturing batch as the LED 10 used as the test object. The predetermined qualified standard may be defined, for example, for each user who manufactures and sells the LED 10 used as the test object.

[0049] The pseudo external quantum efficiency is the same as the generally known original external quantum efficiency, and is calculated by the derived formula: EQE = [P / (I×E)]×100. However, the original external quantum efficiency is based on the luminous efficiency, but the pseudo external quantum efficiency is based on the light receiving efficiency, so the original external quantum efficiency and the pseudo external quantum efficiency become different values. In the derived formula, when deriving the original external quantum efficiency, EQE is the original external quantum efficiency ([%]), P is the luminous intensity of the element ([mW]), I is the current value input to the element ([mA]), and E is the energy of the light, and is the value ([eV]) obtained by dividing the product of Planck's constant and the light beam in a vacuum (1240 [nm·eV]) by the luminous wavelength ([nm]) of the element. When deriving the pseudo external quantum efficiency, EQE is the pseudo external quantum efficiency ([%]), P is the irradiation intensity of light irradiated to the element ([mW]), I is the current value of the photoelectric signal output from the element ([mA]), and E is the energy of the light, which is the value ([eV]) obtained by dividing the product of Planck's constant and the light beam in a vacuum (1240 [nm·eV]) by the light emission wavelength ([nm]) of the element.

[0050] It should be understood that the pseudo external quantum efficiency has a positive correlation with the original external quantum efficiency. Therefore, by using the pseudo external quantum efficiency, the luminescence characteristics of the light-emitting element can be evaluated. In addition, for example, by dividing the original external quantum efficiency of a specific light-emitting element by the pseudo external quantum efficiency of the light-emitting element, the correlation coefficient of the light-emitting element is obtained. The correlation coefficient between the pseudo external quantum efficiency and the original 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 manufacturing batch of the light-emitting element.

[0051] Therefore, the calculation unit 180 of the present embodiment uses the correction coefficient calculated in advance as the correlation coefficient corresponding to the LED 10 to be tested, and calculates the estimated value of the original external quantum efficiency of the LED 10 to be tested obtained from the light emission test based on the pseudo external quantum efficiency of the LED 10 to be tested. The calculation unit 180 uses a correction coefficient that is different depending on the manufacturing batch containing one or more LEDs 10 to be tested. In addition, the multiple LEDs 10 formed on the same wafer 15 are LEDs 10 manufactured according to the same design values, and are LEDs 10 included in the same manufacturing batch. The calculation unit 180 outputs the estimated value of the original external quantum efficiency to the determination unit 190.

[0052] The determination unit 190 determines whether each of the plurality of LEDs 10 to be tested is good or not based on the estimated value of the original external quantum efficiency of each of the plurality of LEDs 10 to be tested. The determination unit 190 may determine whether each of the plurality of LEDs 10 to be tested is good or not, for example, by comparing the original external quantum efficiency with the original external quantum efficiency of the reference LED 10 stored in the storage unit 200, that is, by comparing with a threshold value that serves as a predetermined qualified reference. The determination unit 190 may, for example, identify an LED 10 whose original external quantum efficiency becomes an abnormal value based on the statistical value of the original external quantum efficiency of the plurality of LEDs 10 to be tested, and determine the LED 10 to be defective. The determination unit 190 may further exclude the LED 10 determined to have a defective original external quantum efficiency from the objects of subsequent tests.

[0053] The shielding portion 210 shields light other than the light from the light source 130 and the LED 10. The shielding portion 210 in this embodiment is completely painted black to prevent random reflection of light on the surface. Figure 1 As shown, the shielding portion 210 is provided as a sealed space formed by the lens assembly 143 , the mounting portion 110 , and the wafer 15 . With this configuration, light other than the light from the light source 130 and the LED 10 is shielded.

[0054] Figure 3 The flowchart is an example of a flow chart for explaining the flow of the test method of the test device 100. When the LED group is placed on the placement unit 110, for example, the user inputs an input to the test device 100 to start the test of the LED group. Figure 3 The action flow shown.

[0055] The test device 100 calculates the original external quantum efficiency of the reference LED 10 based on the light emission test of the reference LED 10 (step S101). More specifically, the light emission control unit 160 of the test device 100 supplies a predetermined current to the reference LED 10 via the electrical connection unit 120 while the reference LED 10 is placed on the placement unit 110, thereby causing the reference LED 10 to emit light. The light measurement unit 170 receives light from the reference LED 10 via the optical system 140, measures the wavelength and light emission intensity of the received light, and outputs the measurement result to the calculation unit 180. The wavelength of the light may be, for example, the center wavelength of the synthesized light from the reference LEDs 10.

[0056] The calculation unit 180 calculates the original external quantum efficiency of the reference LED 10 based on the measured wavelength and light intensity of the reference LED 10 and the current input to the reference LED 10 by the light control unit 160. As an example, the calculation unit 180 calculates the original external quantum efficiency of the reference LED 10 by referring to the derivation formula of the original external quantum efficiency 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). More specifically, the light source 130 of the test device 100 irradiates light at a predetermined irradiation intensity to the reference LED 10 or LEDs 10 via the optical system 140. The electrical measurement unit 150 measures the photoelectric signal obtained by photoelectrically converting the light irradiated by each of the reference LED 10 or LEDs 10 via the electrical connection unit 120, and outputs the measurement result to the calculation unit 180. The calculation unit 180 calculates the pseudo external quantum efficiency of each of the reference LED 10 or LEDs 10 based on the irradiation intensity of the light irradiated from the light source 130 to the reference LED 10 or LEDs 10, the wavelength of the reference LED 10 or LEDs 10 measured as the emission wavelength related to the emission of the LED 10 to be tested in step S101, and the photoelectric signal measured by each of the reference LED 10 or LEDs 10.

[0058] The test device 100 calculates the correction coefficient (step S105). More 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 LEDs 10 that serve as a reference by the original external quantum efficiency of the one or more LEDs 10 that serve as a reference. When using a plurality of LEDs 10 that serve as references, the calculation unit 180 may derive an average value of several correction coefficients of the LEDs 10 calculated from the individual pseudo external quantum efficiencies of each LED 10 and the original external quantum efficiencies common to all the LEDs 10, or may select a median value of the plurality of correction coefficients.

[0059] The test device 100 specifies the emission wavelength related to the emission of the LED 10 to be tested based on the power-on test of the LED 10 to be tested (step S107). More specifically, the emission control unit 160 of the test device 100 supplies a predetermined current to the plurality of LEDs 10 to be tested via the electrical connection unit 120 while the plurality of LEDs 10 to be tested are placed on the placement unit 110, thereby causing the LEDs 10 to emit light. The light measurement unit 170 receives the synthesized light from the plurality of LEDs 10 to be tested via the optical system 140, measures the wavelength of the received synthesized light, and outputs the measurement result to the calculation unit 180. The calculation unit 180 specifies the wavelength of the synthesized light from the plurality of LEDs 10 to be tested as the emission wavelength related to the emission of the plurality of LEDs 10 to be tested. The wavelength of the synthesized light may be, for example, the center wavelength of the synthesized light.

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

[0061] The test device 100 calculates an estimated value of the original external quantum efficiency from the pseudo external quantum efficiency of the LED 10 to be tested using the correction coefficient (step S111). More specifically, the calculation unit 180 of the test device 100 calculates an estimated value of the original external quantum efficiency of each of the plurality of LEDs 10 to be tested using the correction coefficient calculated in step S105 from the pseudo external quantum efficiency of each of the plurality of LEDs 10 to be tested. As an example, the calculation unit 180 calculates the original 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 the calculation result to the determination unit 190.

[0062] The test device 100 determines whether the LED 10 to be tested is good or not based on the estimated value of the original external quantum efficiency (step S113), and ends the process. More specifically, as an example, the determination unit 190 of the test device 100 compares the original 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 that the LED 10 whose original external quantum efficiency is less than the threshold value is defective, and excludes it from the subsequent test objects.

[0063] In addition, the test device 100 can also be used Figure 3 The order of the steps in the action flow may be different, and one or more steps may be omitted. Figure 3 In the operation flow of the present invention, the order of step S101 and step S103 may be reversed. In addition, steps S101 to S107 may be omitted. In this case, the test device 100 may obtain the correction coefficient calculated in step S105 and the emission wavelength related to the emission of the LED 10 to be tested measured in step S107 in advance, and store them in the storage unit 200. In addition, the irradiation intensity of the light source 130 in steps S103 and S109 may be the irradiation intensity measured in advance, or may be the set value input to the light source 130.

[0064] As described above, according to the test device 100 of the present embodiment, light from the light source 130 is irradiated onto the LED 10 as the test object, and a photoelectric signal obtained by photoelectric conversion of the irradiated light by the LED 10 as the test object is measured. Based on the irradiation intensity of the light irradiated from the light source 130 to the LED 10 as the test object, the emission wavelength related to the light emission of the LED 10 as the test object, and the measured photoelectric signal of the LED 10 as the test object, a pseudo external quantum efficiency related to the original external quantum efficiency of the LED 10 as the test object is calculated.

[0065] As a comparative example of the test device 100 of the present embodiment, the following device is assumed: a current of a predetermined magnitude is applied to a light-emitting element to be tested to cause it to emit light, and the original external quantum efficiency is calculated by measuring the wavelength and luminous intensity of the light. For example, in a semiconductor test, a plurality of light-emitting elements are arranged adjacent to each other. When the semiconductor test is performed using the device, if the plurality of light-emitting elements are caused to emit light together, the light of the adjacent light-emitting elements is mixed, so that the luminous intensity of each light-emitting element cannot be accurately measured. In this device, in order to avoid this situation, when the plurality of light-emitting elements are caused to emit light in sequence, a large amount of processing time is required to measure the luminous intensity of all the light-emitting elements to calculate the original external quantum efficiency.

[0066] In contrast, according to the test apparatus 100 of the present embodiment, a light having a predetermined intensity is irradiated to the light emitting element to be tested, and a photoelectric signal is outputted, and the pseudo external quantum efficiency is calculated by measuring the photoelectric signal. Even in the case of a semiconductor test in which a plurality of light emitting elements are arranged adjacent to each other, the test apparatus 100 can irradiate light to the plurality of light emitting elements together, measure the photoelectric signal of each light emitting element simultaneously, and calculate the pseudo external quantum efficiency of each light emitting element in parallel in time. Therefore, the test apparatus 100 can also calculate the estimated value of the original external quantum efficiency associated with the pseudo external quantum efficiency of each light emitting element in parallel in time by using the correction coefficient calculated in advance for the light emitting element to be tested. As a result, the test apparatus 100 can significantly shorten the processing time until the estimated value of the original external quantum efficiency of each light emitting element is calculated, that is, the execution time of the test, compared with the apparatus of the comparative example. In addition, the test apparatus 100 can also evaluate the emission characteristics of each light emitting element based on the pseudo external quantum efficiency of each light emitting element.

[0067] In the above-mentioned embodiments, the following configuration is described: the light measuring unit 170 of the test device 100 measures the wavelength of the synthesized light synthesized from the light from each of the plurality of LEDs 10 to be tested and the wavelength of the light from the reference LED 10 as the emission wavelength related to the emission of the plurality of LEDs 10 to be tested. Furthermore, the following configuration is described: the calculation unit 180 of the test device 100 calculates the pseudo external quantum efficiency of each of the plurality of LEDs 10 to be tested using the photoelectric signal of each of the plurality of LEDs 10 to be tested measured by the electrical measurement unit 150 and the wavelength of the synthesized light or the wavelength of the reference LED 10 measured by the light measuring unit 170.

[0068] Alternatively, the light measuring unit 170 of the test device 100 may not measure at least one of the wavelength of the synthesized light obtained by synthesizing the lights from the plurality of LEDs 10 to be tested and the wavelength of the reference LED 10. Alternatively, the test device 100 may not include the light measuring unit 170, in which case the optical system 140 may not include the two-branch fiber 141. When the test device 100 does not measure the wavelength of the synthesized light from the plurality of LEDs 10 to be tested and the wavelength of the reference LED 10, the test device 100 may use a wavelength according to the design value of the reference LED 10, a wavelength previously measured by a light emission test of the reference LED 10, or a wavelength according to the design value of the one or more LEDs 10 to be tested as the light emission wavelength related to the light emission of the one or more LEDs 10 to be tested. The test device 100 may obtain the data of these wavelengths from outside the test device 100, for example, by user input, before calculating the pseudo external quantum efficiency of the LED 10 to be tested, 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 the one or more LEDs 10 as test objects using the photoelectric signals of the one or more LEDs 10 as test objects measured by the electrical measurement unit 150 and these wavelengths.

[0069] In the above embodiments, the light measuring unit 170 of the test device 100 measures the wavelength and emission intensity of light from the reference LED 10 so that the calculation unit 180 calculates the correction coefficient. Furthermore, the calculation unit 180 of the test device 100 calculates the pseudo external quantum efficiency of the reference LED 10 using the photoelectric signal of the reference LED 10 measured by the electrical measuring unit 150 and the wavelength of the reference LED 10 measured by the light measuring unit 170. The calculation unit 180 further calculates the original external quantum efficiency of the reference LED 10 based on the wavelength and emission intensity of the reference LED 10 measured by the light measuring unit 170 and the current input to the reference LED 10 by the emission control unit 160. The calculation unit 180 further calculates the correction coefficient by dividing the pseudo external quantum efficiency of the reference LED 10 by the original external quantum efficiency of the reference LED 10.

[0070] Alternatively, the light measuring unit 170 of the test device 100 may not measure the wavelength of the light from the reference LED 10, and the calculation unit 180 may obtain a correction coefficient corresponding to the LED 10 to be tested from the outside of the test device 100, for example, by user input, before calculating the estimated value of the original external quantum efficiency of the LED 10 to be tested, and store it in the storage unit 200. In this case, the calculation unit 180 of the test device 100 further calculates the estimated value of the original external quantum efficiency of the LED 10 to be tested from the pseudo external quantum efficiency calculated for the LED 10 to be tested, using the correction coefficient obtained from the outside.

[0071] In the above embodiments, the test device 100 may include other mechanisms such as a prism in the optical system 140 instead of the branched fiber such as the two-branched fiber 141. In this case, the prism has the same functional configuration as the two-branched fiber 141 described in the above embodiments.

[0072] In the above multiple embodiments, when the LED group is composed of a plurality of LEDs formed on a panel (PLP) of a glass matrix having a roughly square shape and on which electrical wiring is formed, the electrical connection portion can also be a structure in which the probe is brought into contact with each wiring in the row and column directions arranged on two side surfaces of the panel.

[0073] Various embodiments of the present invention may be described with reference to flow charts and block diagrams, where blocks may represent (1) stages of a process for performing an operation or (2) regions of a device having the function of performing an operation. Specific stages and regions may be implemented by dedicated circuits, programmable circuits supplied with computer-readable instructions stored on a computer-readable medium, and / or processors supplied with computer-readable instructions stored on a computer-readable medium. Dedicated circuits may include digital and / or analog hardware circuits, and may include integrated circuits (ICs) and / or discrete circuits. Programmable circuits may include reconfigurable hardware circuits including memory elements such as logical AND, logical OR, logical XOR, logical NAND, logical NOR, and other logical operations, flip-flops, registers, field programmable gate arrays (FPGAs), programmable logic arrays (PLAs), and the like.

[0074] The computer-readable medium may include any tangible element capable of storing commands executed by appropriate elements, and as a result, the computer-readable medium having the commands stored therein may include an article of manufacture that includes the commands executable to produce a means for performing the operations specified by the flowchart or block diagram. Examples of computer-readable media include electronic storage media, magnetic storage media, optical storage media, electromagnetic storage media, semiconductor storage media, etc. More specific examples of computer-readable media include floppy (registered trademark) disks, magnetic disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), electrically erasable programmable read-only memories (EEPROM), static random access memories (SRAM), compact disk read-only memories (CD-ROM), digital versatile disks (DVD), blue-ray (RTM) disks, memory sticks, integrated circuit cards, etc.

[0075] The computer-readable instructions may include any source code or object code described in any combination of one or more programming languages, including assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or target-oriented programming languages ​​such as Smalltalk (registered trademark), JAVA (registered trademark), C++, and conventional procedural programming languages ​​such as the "C" programming language or similar programming languages.

[0076] Computer-readable instructions are provided to a processor or programmable circuit of a programmable data processing device such as a computer via a wide area network (WAN) such as a local area network (LAN) or the Internet, and the computer-readable instructions can be executed to form a means for performing the operations specified by the flowchart or block diagram. Here, the computer can be a PC (personal computer), a tablet computer, a smart phone, a workstation, a server computer, a general-purpose computer, or a special-purpose computer, or a computer system connected to multiple computers. Such a computer system connected to multiple computers is called a distributed computing system, which is a computer in a broad sense. In a distributed computing system, multiple computers each execute a part of a program, and data in the execution of the program is transmitted between computers as needed, so that multiple computers collectively execute the program.

[0077] Examples of processors include computer processors, central processing units (CPUs), processing components, microprocessors, digital signal processors, controllers, microcontrollers, and the like. A computer may have one processor or multiple processors. In a multiprocessor system having multiple processors, each processor executes a portion of a program, and data in the execution of the program is transmitted between processors as needed, so that the multiple processors collectively execute the program. For example, in the execution of multiple tasks, each of the multiple processors executes a portion of each task in fragments by switching tasks for each time slice. In this case, which part of a program is executed by each processor changes dynamically. Which part of the program is executed by each of the multiple processors can also be statically determined by programming that makes the multiple processors aware.

[0078] Figure 4 The computer 1200 is an example of a computer that can implement various aspects of the present invention in whole or in part. The program installed in the computer 1200 can cause the computer 1200 to function as an operation associated with a device according to an embodiment of the present invention or one or more regions of the device, or can execute the operation or the one or more regions, and / or can cause the computer 1200 to execute a process according to an embodiment of the present invention or a stage of the process. In order to cause the computer 1200 to execute specific operations associated with some or all of the blocks in the flowcharts and block diagrams described in this specification, the program can be executed by the CPU 1212.

[0079] The computer 1200 of this embodiment includes a CPU 1212, a RAM 1214, a graphics controller 1216, and a display device 1218, which are connected to each other by a host controller 1210. The computer 1200 also includes input / output components 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 the input / output controller 1220. The computer also includes conventional input / output components such as a ROM 1230 and a keyboard 1242, which are connected to the input / output controller 1220 via an input / output chip 1240.

[0080] The CPU 1212 operates according to the programs stored in the ROM 1230 and the RAM 1214 to control each component. The graphic controller 1216 obtains the image data generated by the CPU 1212 in the frame buffer or the like provided in the RAM 1214 or in itself, and displays the image data on the display device 1218.

[0081] The communication interface 1222 communicates with other electronic components via a network. The hard disk drive 1224 stores programs and data 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 an IC card.

[0082] The ROM 1230 stores therein a startup program etc. executed by the computer 1200 when activated, and / or a program that depends on the hardware of the computer 1200. The input / output chip 1240 can additionally connect various input / output components to the input / output controller 1220 via a parallel port, a serial port, a keyboard port, a mouse port, etc.

[0083] The program is provided by a computer-readable medium such as DVD-ROM 1201 or an IC card. The program is read from the computer-readable medium and installed in the hard disk drive 1224, RAM 1214, or ROM 1230, which is also an example of a computer-readable medium, and is executed by the CPU 1212. The information processing described in these programs is read by the computer 1200, resulting in the combination between the program and the various types of hardware resources described above. The device or method can be constructed by implementing the operation or processing of information according to the use of the computer 1200.

[0084] For example, when the computer 1200 communicates with an external device, the CPU 1212 executes a communication program loaded in the RAM 1214, and can instruct the communication interface 1222 to perform communication processing according to the processing described in the communication program. Under the control of the CPU 1212, the communication interface 1222 reads the transmission data stored in the transmission buffer processing area provided to the RAM 1214, the hard disk drive 1224, the DVD-ROM 1201, or a recording medium such as an IC card, and transmits the read transmission data to the network, or writes the reception data received from the network to the reception buffer processing area provided to the recording medium.

[0085] In addition, the CPU 1212 can read all or a necessary part of a file or database stored in an external recording medium such as the hard disk drive 1224, the DVD-ROM drive 1226 (DVD-ROM 1201), or an IC card into the RAM 1214, and perform various types of processing on the data on the RAM 1214. The CPU 1212 then writes the processed data back to the external recording medium.

[0086] Various types of information such as various types of programs, data, tables, and databases can be stored in the recording medium and receive information processing. The CPU 1212 can perform various types of processing including various types of operations specified by the command sequence of the program, information processing, conditional judgment, conditional branching, unconditional branching, information retrieval / replacement, etc., which are recorded anywhere in the present invention, on the data read from the RAM 1214, and write the results back to the RAM 1214. In addition, the CPU 1212 can retrieve information in files, databases, etc. in the recording medium. For example, in the case where a plurality of input values ​​having attribute values ​​of the first attribute each associated with an attribute value of the second attribute are stored in the recording medium, the CPU 1212 can retrieve an input value that matches the condition specified by the attribute value of the first attribute from among the plurality of input values, read the attribute value of the second attribute stored in the input value, and thereby obtain the attribute value of the second attribute associated with the first attribute that satisfies the predetermined condition.

[0087] The program or software module described above may be stored in a computer-readable medium on or near the computer 1200. In addition, a recording medium such as a hard disk or RAM provided to a server system connected to a dedicated communication network or the Internet can be used as a computer-readable medium, thereby providing the program to the computer 1200 via the network.

[0088] The present invention has been described above using the embodiments, but the technical scope of the present invention is not limited to the scope described in the embodiments. It is clear to those skilled in the art that various changes or improvements can be added to the embodiments. It is clear that the forms to which various changes or improvements are added according to the description of the claims are also included in the technical scope of the present invention.

[0089] It should be noted that the execution order of each process such as actions, sequences, steps, and stages in the devices, systems, programs, and methods shown in the claims, specifications, and drawings can be implemented in any order unless it is specifically stated as "before" or "before", and the output of the previous process is not used for the subsequent process. Even if the action flow in the claims, specifications, and drawings is described using "first," "next," etc. for convenience, it does not mean that it must be implemented in this order.

Explanation of symbols

[0090] 10: LED 11: Terminal 15: Wafer 100: Test device 110: Loading section 111: Through hole 120: Electrical connection 121: Substrate 123: Probe 130: Light source 140: Optical system 150: Electrical measurement unit 160: Lighting control unit 170: Light Measurement Unit 180: Calculation Department 190: Judgment Department 200: Storage 210: Shield 1200: Computer 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 Drive 1226: DVD-ROM drive 1230: ROM 1240: Input / output chip 1242: Keyboard

Claims

1. A test device comprising: light source; An electrical measuring unit that measures a photoelectric signal obtained by photoelectrically converting light irradiated from the light source by a light emitting element to be tested; and A calculation unit calculates a pseudo external quantum efficiency associated with an original external quantum efficiency of the light-emitting element as a test object based on the irradiation intensity of light irradiated from the light source to the light-emitting element as a test object, the emission wavelength related to the emission of the light-emitting element as a test object, and the measured photoelectric signal of the light-emitting element as a test object.

2. The test device according to claim 1, wherein The calculation unit uses a correction factor based on the pseudo external quantum efficiency calculated in advance for the benchmark light-emitting element and the original external quantum efficiency calculated in advance from a light-emitting test for the benchmark light-emitting element, and calculates an estimated value of the original external quantum efficiency of the light-emitting element that is the test object, obtained from the light-emitting test, based on the pseudo external quantum efficiency of the light-emitting element that is the test object.

3. The test device according to claim 2, wherein The reference light emitting element is an ideal light emitting element based on the design value of the test object light emitting element, or a light emitting element that meets a predetermined acceptance standard and is included in the same manufacturing batch as the test object light emitting element.

4. The test device according to claim 2, wherein The emission wavelength related to the emission of the light-emitting element that is the test object is a wavelength based on the design value of the light-emitting element that serves as the benchmark, a wavelength of the light-emitting element that is the benchmark and is pre-measured by the emission test, or a wavelength based on the design value of the light-emitting element that serves as the test object.

5. The test device according to claim 2, further comprising: a light emitting control unit that causes the reference light emitting element to emit light; and a light measuring unit for measuring the wavelength and light intensity of light from the light emitting element serving as a reference; The calculation unit The pseudo external quantum efficiency of the reference light-emitting element is calculated based on the irradiation intensity of the light irradiated from the light source to the reference light-emitting element, the wavelength of the reference light-emitting element measured as the emission wavelength related to the emission of the light-emitting element of the test object, and the measured photoelectric signal of the reference light-emitting element, calculating the original external quantum efficiency of the reference light-emitting element based on the measured wavelength and the light emission intensity of the reference light-emitting element and the current input to the reference light-emitting element by the light emission control unit, The correction coefficient is calculated by dividing the pseudo external quantum efficiency by the actual external quantum efficiency.

6. The test device according to claim 5, further comprising: The optical system irradiates the light from the light source incident in one direction toward the reference light emitting element, and irradiates the light from the reference light emitting element incident in another direction toward the light measuring unit.

7. The test device according to any one of claims 1 to 6, wherein The electrical measuring unit measures the photoelectric signal obtained by photoelectrically converting the light emitted from the light source by each of the plurality of light emitting elements to be tested. The calculation unit calculates the pseudo external quantum efficiency of each of the multiple light-emitting elements that are the test objects based on the irradiation intensity of the light irradiated from the light source to the multiple light-emitting elements that are the test objects, the emission wavelength related to the light emission of the multiple light-emitting elements that are the test objects, and the photoelectric signal measured for each of the multiple light-emitting elements that are the test objects.

8. The test device according to claim 7, wherein The calculation unit uses a correction coefficient based on the pseudo external quantum efficiency calculated in advance for the benchmark light-emitting element and the original external quantum efficiency calculated in advance for the benchmark light-emitting element from a light-emitting test, and calculates an estimated value of the original external quantum efficiency of each of the multiple light-emitting elements that are the test objects obtained from the light-emitting test based on the pseudo external quantum efficiency of each of the multiple light-emitting elements that are the test objects.

9. The test device according to claim 8, wherein The calculation unit uses the correction coefficient that differs according to a manufacturing lot including the plurality of light emitting elements to be tested.

10. The test device according to claim 8, further comprising: The determination unit determines whether each of the plurality of light-emitting elements to be tested is good or not based on the estimated value of the original external quantum efficiency of each of the plurality of light-emitting elements to be tested.

11. The test device according to claim 7, further comprising: A light emitting control unit, which makes the plurality of light emitting elements serving as test objects emit light together; a light measuring unit that measures a wavelength of synthesized light obtained by synthesizing the lights from the plurality of light emitting elements as test objects as the emission wavelength associated with the emission of the plurality of light emitting elements as test objects; and The optical system irradiates the plurality of light emitting elements as test objects with light from the light source incident in one direction, and irradiates the light measuring unit with synthesized light obtained by synthesizing light from each of the plurality of light emitting elements as test objects incident in another direction.

12. A test method comprising: irradiating light from a light source to a light emitting element to be a test object; measuring a photoelectric signal obtained by photoelectrically converting the irradiated light by the light-emitting element serving as the test object; and Based on the irradiation intensity of light from the light source to the light-emitting element as the test object, the emission wavelength related to the light emission of the light-emitting element as the test object, and the measured photoelectric signal of the light-emitting element as the test object, a pseudo external quantum efficiency related to the original external quantum efficiency of the light-emitting element as the test object is calculated.

13. A computer-readable storage medium storing a program for causing a test device for testing a light-emitting element to execute the following sequence: irradiating light from a light source to a light emitting element to be a test object; measuring a photoelectric signal obtained by photoelectrically converting the irradiated light by the light-emitting element serving as the test object; and Based on the irradiation intensity of light from the light source to the light-emitting element as the test object, the emission wavelength related to the light emission of the light-emitting element as the test object, and the measured photoelectric signal of the light-emitting element as the test object, a pseudo external quantum efficiency related to the original external quantum efficiency of the light-emitting element as the test object is calculated.

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