External quantum efficiency detection system and detection method of micro-area light-emitting element

Abstract

The present invention provides a detection system and method for external quantum efficiency of a light-emitting element under a micro-area, the detection system comprising: a receiving light path, comprising a first microscope objective lens and a first detection device for measuring light intensity, the first detection device being aligned with the rear end of the first microscope objective lens; a calibration device for obtaining a response function of the receiving light path, comprising a light source, a condenser for converging light on the focal plane of the first microscope objective lens, a conductive member for introducing light of different frequencies into the front end of the first microscope objective lens, and a second detection device for measuring the spectral intensity distribution of light of different frequencies on the focal plane, the first end of the condenser being aligned with the light source, the second end of the condenser being aligned with the focal plane, the conductive member being arranged on the focal plane; and a third detection device for measuring the current of the light-emitting element to be measured. The present invention solves the problem of poor accuracy of traditional external quantum efficiency detection devices when detecting single-pixel or sub-millimeter-level micro-sized light-emitting devices.

Description

Technical Field

[0001] The present invention relates to the technical field of light-emitting component detection, and in particular to an external quantum efficiency detection system and a detection method of a light-emitting component in a micro area. Background Art

[0002] External quantum efficiency is one of the important parameters used to characterize light-emitting devices.

[0003] In recent years, with the continuous development of electronic technology, people's requirements for high-performance flat panel displays have continued to increase. Smaller single pixel size and lower energy consumption have always been the pursuit of the light-emitting device industry. Existing optimization methods usually improve the external quantum efficiency of light-emitting devices through device material and processing technology design, or through micro-nano structure design.

[0004] In the early stages of research and development to improve the external quantum efficiency of light-emitting devices, in order to consider time and cost factors, usually only single-pixel or sub-millimeter scale or even smaller sample light-emitting devices are prepared. The problem that is faced is that as the light-emitting surface of the light-emitting device decreases, its luminous flux decreases accordingly, and conventional external quantum efficiency detection devices (generally based on an integrating sphere system) cannot accurately detect the external quantum efficiency of such small-sized light-emitting devices. Summary of the invention

[0005] In order to overcome the defects of the prior art, a micro-area light-emitting device external quantum efficiency detection system and detection method are provided to solve the problem of poor accuracy of traditional external quantum efficiency detection devices when detecting single-pixel or sub-millimeter-level tiny-sized light-emitting devices.

[0006] In order to achieve the above object, a system for detecting the external quantum efficiency of a light-emitting device under a micro-area is provided, comprising:

[0007] A receiving optical path, comprising a first microscope objective lens for collecting incident light and a first detection device for measuring the light intensity of the incident light, wherein the first detection device is aligned with the rear end of the first microscope objective lens;

[0008] A calibration device for obtaining a response function of the receiving optical path to incident light of different frequencies, comprising a light source for emitting light of different frequencies, a condenser for converging the light of different frequencies on a focal plane at the front end of the first microscope objective lens, a conductive member for guiding the light of different frequencies converged on the focal plane to the front end of the first microscope objective lens, and a second detection device for measuring the spectral intensity distribution of the light of different frequencies converged on the focal plane, wherein a first end of the condenser is aligned with the light source, a second end of the condenser is aligned with the focal plane, and the conductive member is arranged on the focal plane; and

[0009] The third detection device is used to measure the current when the light-emitting element to be tested emits light.

[0010] Furthermore, the receiving optical path also includes a coupling member, the coupling member is aligned with the rear end of the first microscope objective lens, and the first detection device is aligned with the coupling member.

[0011] Furthermore, the conductive member is a light-transmitting medium, the focusing member is a second microscope objective lens, the rear end of the second microscope objective lens is aligned with the light source, the front end of the second microscope objective lens is arranged opposite to the front end of the first microscope objective lens, and the focal plane of the second microscope objective lens coincides with the focal plane of the first microscope objective lens.

[0012] Furthermore, the conductive member is a reflective element, the focusing member is a third microscope objective lens, the rear end of the third microscope objective lens is aligned with the light source, the front end of the third microscope objective lens is arranged opposite to the front end of the first microscope objective lens, and the focal plane of the third microscope objective lens, the focal plane of the first microscope objective lens and the reflective surface of the reflective element are all compared to a straight line.

[0013] Furthermore, the focal plane of the third microscope objective lens, the focal plane of the first microscope objective lens and the reflective surface of the reflective element coincide with each other, and the first microscope objective lens and the third microscope objective lens are the same microscope objective lens.

[0014] Furthermore, the reflective element is a specular reflective element or a diffuse reflective element.

[0015] Furthermore, the first detection device is a photoelectric light intensity detection device.

[0016] Furthermore, the photoelectric light intensity detection device is any one of a spectrometer, a brightness meter, a power meter, a CCD, a CMOS, a PMT, and a single photon detector.

[0017] The present invention provides a method for detecting the external quantum efficiency of a light-emitting element in a micro-area, comprising the following steps:

[0018] The light source emits light of different frequencies and converges the light of different frequencies on the focal plane at the front end of the first microscope objective lens;

[0019] Determining the spectral intensity distribution of the light of different frequencies focused on the focal plane;

[0020] The conductive member is arranged on the focal plane, the conductive member guides the light of different frequencies into the front end of the first microscope objective lens, the light of different frequencies is emitted through the rear end of the first microscope objective lens, and the light intensity of the emitted light of different frequencies is measured;

[0021] Calculating and obtaining the response function of the receiving optical path to light of different frequencies;

[0022] Placing a light-emitting element to be tested on the focal plane and energizing the light-emitting element to be tested, so that the light-emitting element to be tested emits light to generate incident light, the incident light enters the front end of the first microscope objective lens and is emitted through the rear end of the first microscope objective lens, and the light intensity of the emitted incident light is measured;

[0023] Calculating and obtaining the luminous spectrum intensity distribution of the luminous element to be tested;

[0024] Determining the current value of the light-emitting element to be tested when it emits light;

[0025] The external quantum efficiency of the light-emitting element to be tested is obtained.

[0026] Furthermore, the step of obtaining the external quantum efficiency of the light-emitting element to be tested includes:

[0027] Acquire the luminous spectrum intensity distribution of the luminous element to be tested at different angles and the receiving angle of the first microscope objective lens to obtain the real luminous spectrum intensity distribution of the luminous element to be tested;

[0028] The external quantum efficiency of the light-emitting element to be tested is obtained by calculation according to the actual luminous spectrum intensity distribution and the current value of the light-emitting element to be tested.

[0029] The beneficial effect of the present invention lies in that the external quantum efficiency detection system of the micro-area light-emitting component of the present invention utilizes the first microscope objective lens to collect the luminous signal of the tiny-sized light-emitting device and improves the light signal receiving efficiency, utilizes the second detection device to calibrate the spectral intensity distribution of the incident light in the focal plane of the first microscope objective lens, and then combines with the calibration equipment to calibrate the response function of the receiving optical path to light of different frequencies, so as to improve the efficiency and accuracy of the measurement of the external quantum efficiency of the tiny light-emitting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of an external quantum efficiency detection system of a micro-area light-emitting element according to an embodiment of the present invention.

[0031] Figure 2 The figure is a flow chart of a method for detecting the external quantum efficiency of a light-emitting element under a micro-area according to an embodiment of the present invention.

[0032] Figure 3 It is a schematic structural diagram of the external quantum efficiency detection system of the micro-area light-emitting element according to the first embodiment of the present invention.

[0033] Figure 4 It is a schematic structural diagram of the external quantum efficiency detection system of the micro-area light-emitting element according to the second embodiment of the present invention. DETAILED DESCRIPTION

[0034] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0035] Figure 1 Schematic diagram of the external quantum efficiency detection system of the micro-area light-emitting element according to an embodiment of the present invention, Figure 2 Flow chart of the external quantum efficiency detection method of the micro-area light-emitting element according to the embodiment of the present invention, Figure 3 The schematic diagram of the structure of the external quantum efficiency detection system of the micro-area light-emitting element according to the first embodiment of the present invention is as follows; Figure 4 It is a schematic structural diagram of the external quantum efficiency detection system of the micro-area light-emitting element according to the second embodiment of the present invention.

[0036] Reference Figures 1 to 4 As shown, the present invention provides a system for detecting the external quantum efficiency of a light-emitting element in a micro-area, comprising: a receiving optical path 1, a calibration device 2 and a third detection device 3.

[0037] Specifically, the receiving optical path 1 includes a first microscope objective lens 11 and a first detection device 12. The first microscope objective lens 11 is used to collect incident light. In this embodiment, the incident light includes light collected from the luminous element to be detected and light generated by the light source mentioned below and introduced through the focusing element and the conducting element.

[0038] The first detection device 12 is used to measure the light intensity I(λ) of the incident light entering the first microscope objective. The first microscope objective has a front end and a rear end. The front end of the first microscope objective is the end that is aligned with the object to be observed, the stage or the cover glass when observing the micro object in a conventional manner, and the rear end of the first microscope objective is the end that is opposite to the object to be observed, the stage or the cover glass when observing the micro object in a conventional manner. The first detection device 12 is aligned with the rear end of the first microscope objective 11.

[0039] The calibration device 2 is used to obtain the response function H(λ) of the receiving optical path 1 to incident light of different frequencies.

[0040] Specifically, the calibration device 2 includes a light source 21 , a focusing element 22 , a conducting element 23 and a second detection device 24 .

[0041] The light source 21 is used to emit light of different frequencies. The focusing element 22 is used to focus the light of different frequencies generated by the light source 21 on the focal plane at the front end of the first microscope objective lens 11 .

[0042] The conductive member 23 is used to guide the light beams of different frequencies converged on the focal plane of the first microscope objective lens 11 into the front end of the first microscope objective lens 11 .

[0043] The second detection device 24 is used to measure the spectral intensity distribution S of the light of different frequencies converged on the focal plane of the first microscope objective 11. c (λ).

[0044] The first end of the condenser 22 is aligned with the light source 21, and the second end of the condenser 22 is aligned with the focal plane of the first microscope objective 11. The transmission element 23 is disposed on the focal plane, and the transmission element 23 has a known absolute reflectivity or transmittance R(λ).

[0045] The third detection device 3 is used to measure the current value A of the light-emitting element 4 to be tested when it emits light.

[0046] The external quantum efficiency detection system of the micro-area light-emitting component of the present invention utilizes a first microscope objective lens to collect the luminous signal of the micro-sized light-emitting device and improve the light signal receiving efficiency, utilizes a second detection device to calibrate the spectral intensity distribution of the incident light in the focal plane of the first microscope objective lens, and then combines with the calibration equipment to calibrate the response function of the receiving optical path to light of different frequencies, so as to improve the efficiency and accuracy of the measurement of the external quantum efficiency of the micro-light-emitting device.

[0047] As a preferred embodiment, the receiving optical path 1 further includes a coupling member 13. The coupling member is a fiber coupler. The first end of the coupling member 13 is aligned with the rear end of the first microscope objective lens 11, and the first detection device 12 is aligned with the second end of the coupling member 13.

[0048] The conductive element 23 is a light-transmitting medium or a reflective element. The first microscope objective lens is a transmission microscope objective lens or a reflection microscope objective lens.

[0049] For details, see Figure 4 As shown, the conductive member 23 is a light-transmitting medium. The first microscope objective lens 11 is a transmission microscope objective lens or a reflection microscope objective lens. The focusing member 22 is a second microscope objective lens. The second microscope objective lens is coaxially arranged with the second microscope objective lens, wherein the rear end of the second microscope objective lens is aligned with the light source 21, the front end of the second microscope objective lens is aligned with the front end of the first microscope objective lens, and the focal plane of the second microscope objective lens coincides with the focal plane of the first microscope objective lens. The rear end of the second microscope objective lens is aligned with the light source 21. The conductive member 23 is a light-transmitting medium, and further a wide-spectrum highly transparent medium. Continue to refer to Figure 4 As shown, the conductive member is, for example, air.

[0050] When calibrating the spectral intensity distribution of light of different frequencies at the focal plane position of the first microscope objective lens, the light source generates incident light, which is converged at the focal plane of the first microscope objective lens through the second microscope objective lens (the incident light enters from the rear end of the second microscope objective lens and is emitted from the front end of the second microscope objective lens), and the first detection device measures the spectral intensity distribution of light of different frequencies converged at the focal plane of the first microscope objective lens.

[0051] When obtaining the response function of the receiving optical path to light of different frequencies, the light source generates incident light, which is converged at the focal plane of the first microscope objective lens through the second microscope objective lens, and is introduced into the front end of the first microscope objective lens through the transmission medium (air) and then emitted from the rear end of the first microscope objective lens (the incident light enters from the front end of the first microscope objective lens and is emitted from the rear end of the first microscope objective lens). The first detection device measures the light intensity of light of different frequencies emitted from the rear end of the first microscope objective lens.

[0052] After obtaining the response function and the spectral intensity distribution of light of different frequencies at the focal plane position of the first microscope objective lens, the luminous element 4 to be tested is placed at the focal plane of the first microscope objective lens, and then the power supply 41 and the third detection device 3 are respectively connected to the luminous element 4 to be tested placed on the focal plane, the power supply 41 supplies power to the luminous element 4 to be tested to make it emit light, and the third detection device 3 measures the current value of the luminous element 4 to be tested when it emits light. The luminous element to be tested generates incident light, which is emitted through the rear end of the first microscope objective lens (the incident light enters from the front end of the first microscope objective lens and is emitted from the rear end of the first microscope objective lens), and the first detection device measures the light intensity of the incident light generated by the luminous element to be tested.

[0053] In some embodiments, the conductive element 23 is a reflective element, and the focusing element 22 is a third microscope objective lens. Figure 4 The difference is that the third microscope objective lens is arranged at an angle with the first microscope objective lens. The front end of the third microscope objective lens is arranged opposite to the front end of the first microscope objective lens and is simultaneously aligned with the reflecting surface of the reflecting element. The rear end of the third microscope objective lens is aligned with the light source. The focal plane of the third microscope objective lens, the focal plane of the first microscope objective lens and the reflecting surface of the reflecting element are simultaneously compared to a straight line.

[0054] When obtaining the response function of the receiving optical path to light of different frequencies, the light source generates incident light, which is converged at the focal plane of the first microscope objective lens through the third microscope objective lens (enters from the rear end of the third microscope objective lens and is emitted from the front end of the third microscope objective lens), and is reflected to the front end of the first microscope objective lens through the reflective element (aluminum mirror) and then emitted from the rear end of the first microscope objective lens. The first detection device measures the light intensity of light of different frequencies emitted from the rear end of the first microscope objective lens.

[0055] As a preferred implementation, see Figure 3As shown, the conductive member 23 is a reflective element, the first microscope objective lens is perpendicular to the reflective surface of the reflective element, and the reflective surface of the reflective element coincides with the focal plane of the first microscope objective lens. At this time, the first microscope objective lens 11 and the focusing member 22 can share the same microscope objective lens. Figure 3 The reflective element shown is a specular reflective element or a diffuse reflective element. Figure 3 In the embodiment, the reflective element is an aluminum mirror.

[0056] When calibrating the spectral intensity distribution of light of different frequencies at the focal plane position of the first microscope objective lens, the light source generates incident light, which converges at the focal plane of the first microscope objective lens through the first microscope objective lens (the incident light enters from the rear end of the first microscope objective lens and is emitted from the front end of the second microscope objective lens), and the first detection device measures the spectral intensity distribution of light of different frequencies converged at the focal plane of the first microscope objective lens.

[0057] When obtaining the response function of the receiving optical path to light of different frequencies, the light source generates incident light, which is converged at the focal plane of the first microscope objective lens through the first microscope objective lens, and is reflected by the reflecting element to enter the first microscope objective lens again from the front end and then emitted from the rear end of the first microscope objective lens. The first detection device measures the light intensity of the light of different frequencies emitted from the rear end of the first microscope objective lens.

[0058] After obtaining the response function and the spectral intensity distribution of light of different frequencies at the focal plane position of the first microscope objective lens, the luminescent element 4 to be tested is placed at the focal plane of the first microscope objective lens, and then the power supply 41 and the third detection device 3 are respectively connected to the luminescent element 4 to be tested placed on the focal plane, the power supply 41 supplies power to the luminescent element 4 to be tested to make it emit light, and the third detection device 3 measures the current value of the luminescent element 4 to be tested when it emits light. The luminescent element to be tested generates incident light, which enters through the front end of the first microscope objective lens and is emitted from the rear end of the first microscope objective lens, and the first detection device measures the light intensity of the incident light generated by the luminescent element to be tested.

[0059] In this embodiment, the first detection device 12 is any one of a spectrometer, a brightness meter, a power meter, a CCD (charge coupled device), a CMOS (Complementary Metal Oxide Semiconductor), a PMT (photomultiplier tube, used to detect weak light signals from weak emission sources), and a single photon detector.

[0060] In this embodiment, the light source is a monochromatic light source or a broadband light source.

[0061] As a preferred implementation, the second detection device 24 is a spectrum detection system with an absolute irradiance calibrated integrating sphere or a cosine corrector as a receiving end.

[0062] In this embodiment, the power supply and the third detection device are source meters.

[0063] The present invention provides a detection method of an external quantum efficiency detection system of a micro-area light-emitting element, characterized in that it comprises the following steps:

[0064] S1: The light source 21 emits light of different frequencies, and the focusing element 22 focuses the light of different frequencies on the focal plane at the front end of the first microscope objective lens 11 of the receiving light path 1.

[0065] S2: The second detection device 24 respectively measures the spectral intensity distribution S of the light of different frequencies converged on the focal plane of the first microscope objective lens 11 c (λ), where λ is the wavelength.

[0066] S3: The transmission element 23 is arranged on the focal plane of the first microscope objective lens 11. The absolute reflectivity or transmittance of the transmission element 23 is R(λ). The transmission element 23 guides the light of different frequencies into the front end of the first microscope objective lens 11. The light of different frequencies is incident into the coupling element 13 of the receiving optical path 1 through the rear end of the first microscope objective lens 11 and then incident into the first detection device 12 of the receiving optical path 1 after being coupled by the coupling element 13. The first detection device 12 measures the light intensity I of the incident light of different frequencies. c (λ).

[0067] S4: According to formula I c (λ) = S c (λ)×R(λ)×H(λ), calculate and obtain the response function H(λ) of the receiving optical path 1 to light of different frequencies.

[0068] S5: The luminous element 4 to be tested is placed on the focal plane of the first microscope objective 11 and energized, so that the luminous element 4 to be tested emits light to generate incident light, and the incident light enters the front end of the first microscope objective 11 and is coupled by the coupling element 13 at the rear end of the first microscope objective 11 and then enters the first detection device 12. The first detection device 12 measures the light intensity I of the incident light. x (λ).

[0069] S6: According to formula S x (λ)=I x (λ) / H(λ), calculate and obtain the luminous spectrum intensity distribution S of the luminous element 4 to be tested x (λ).

[0070] S7: The third detection device 3 measures the current value A of the light-emitting element 4 to be tested when it emits light.

[0071] S8: Based on the spectral intensity distribution S of the light emitting element 4 to be tested x (λ) and current value, and obtain the external quantum efficiency η of the light-emitting element 4 to be tested EQE .

[0072] Specifically, step S8 includes:

[0073] S81, according to the spectral intensity distribution S of the light-emitting element 4 to be tested x (λ), and use the Lambertian distribution model to calculate the actual luminous spectrum intensity distribution S of the luminous element 4 to be tested x0 (λ).

[0074] S82, based on the calculated real luminous spectrum intensity distribution S of the luminous element 4 to be tested x0 (λ) and the measured current value A, calculate the external quantum efficiency η of the light-emitting element 4 to be tested EQE .

[0075] External quantum efficiency calculation formula: Where h is Planck's constant, which is 6.62607×10 - 34 J·s, c is the speed of light, i.e. 3×10 8 m / s, e is the charge of a single electron, which is 1.602189×10 -19 C.

[0076] In addition, according to the measured spectral intensity distribution S of the light-emitting element to be tested x0 (λ), the optical parameters of the light-emitting component such as luminous efficiency, luminous flux, luminous intensity, luminance (brightness), color coordinates, color temperature, main wavelength, peak wavelength, half-peak width, etc. can also be obtained, and the IVL curve can be obtained at the same time.

[0077] In order to more clearly illustrate the external quantum efficiency detection system and detection method of the micro-area light-emitting element of the present invention, the following embodiments are listed to further illustrate and describe.

[0078] First embodiment

[0079] Reference Figures 1 to 3As shown, the external quantum efficiency detection system of the micro-area light emitting element of the embodiment of the present invention includes: a light source 21, which uses a xenon lamp light source with a monochromator to provide monochromatic light covering 250nm to 1700nm from ultraviolet to near-infrared; a focusing element (i.e., a third microscope objective lens, the third microscope objective lens and the first microscope objective lens are the same microscope objective lens), which is used to receive the light of the light source and converge it on the focal plane of the first microscope objective lens; a transmission element, which uses an aluminum mirror with a known absolute reflectivity R (λ); a receiving light path, which includes the first microscope objective lens, a coupling element 13 and a first detection device 12. The first microscope objective lens is used to collect the light signal on the focal plane of the first microscope objective lens. In this embodiment, the focusing element and the first microscope objective lens are the same microscope objective lens; the first detection device uses a single-point light detector to detect the spectrum and intensity I(λ) of the light signal received by the receiving light path; the power supply 41 is a source meter in this embodiment, which is used to provide power to the light-emitting element to be tested to light it; the third detection device 3 is used to detect the current when the light-emitting element to be tested emits light; in this embodiment, the power supply and the third detection device are the same device, namely, a power source meter.

[0080] In this embodiment, the detection method of the external quantum efficiency detection system of the micro-area light-emitting element of the embodiment of the present invention has the following steps:

[0081] S1: The light source 21 of the calibration device 2 emits light of different frequencies, which are injected from the rear end of the first microscope objective lens (i.e., the third microscope objective lens) and then converged from the front end of the first microscope objective lens onto the focal plane at the front end of the first microscope objective lens 11 of the receiving optical path 1.

[0082] The light source is a xenon lamp light source with a monochromator, which outputs monochromatic light; the light source 21 is converged to the focal plane of the first microscope objective lens through a condenser.

[0083] S2: The second detection device 24 of the calibration device 2 measures the spectral intensity distribution S of the light of different frequencies converged on the focal plane of the first microscope objective (i.e., the first microscope objective). c (λ).

[0084] The optical signal converged by the light source under the first microscope objective is collected and detected by a spectrum detection system at the receiving end using an integrating sphere calibrated with absolute irradiance.

[0085] The monochromator changes the output wavelength of the light source by rotating the grating. At different wavelengths, the spectral intensity distribution S of the light source at the focal plane of the first microscope objective lens after passing through the condenser can be c (λ). So far, the spectral intensity calibration of the light of different frequencies output by the xenon lamp light source and the monochromator at the focal plane of the first microscope objective has been completed.

[0086] S3: The conductive member 23 of the calibration device 2 is set on the focal plane of the first microscope objective lens 11. The conductive member 23 has a known absolute reflectivity or transmittance R(λ). The conductive member is a reflective element, and the reflective surface of the reflective element coincides with the focal plane of the first microscope objective lens. The reflective element reflects the light of different frequencies and guides it to the front end of the first microscope objective lens 11. The light of different frequencies is injected into the coupling member 13 of the receiving optical path 1 through the rear end of the first microscope objective lens 11 and then injected into the first detection device 12 of the receiving optical path 1 after coupling through the coupling member 13. The first detection device 12 measures the light intensity I of the injected light of different frequencies. c (λ).

[0087] An aluminum mirror with an absolute reflectivity of R(λ) is placed at the focal plane of the first microscope objective. Figure 3 In the embodiment shown, the reflective surface of the aluminum mirror is arranged to coincide with the focal plane of the first microscope objective lens. The aluminum mirror reflects the monochromatic light of different frequencies output by the light source and injects it into the front end of the first microscope objective lens. The monochromatic light of different frequencies is coupled by the coupling element and injected into the first detection device. The first detection device measures the intensity I of the monochromatic light. c The light source is scanned by a monochromator to obtain the intensity of light of different frequencies. c (λ).

[0088] S4: According to formula I c (λ) = S c (λ)×R(λ)×H(λ), calculate and obtain the response function H(λ) of the receiving optical path 1 to light of different frequencies.

[0089] According to I c (λ) = S c (λ)×R(λ)×H(λ), the response function H(λ) of the receiving optical path to light of different frequencies can be calculated, thus completing the calibration of the response function of the receiving optical path to light of different frequencies.

[0090] S5: The luminous element 4 to be tested is placed on the focal plane of the first microscope objective 11 and energized, so that the luminous element 4 to be tested emits light to generate incident light, and the incident light enters the front end of the first microscope objective 11 and is coupled by the coupling element 13 at the rear end of the first microscope objective 11 and then enters the first detection device 12. The first detection device 12 measures the light intensity I of the incident light. x (λ).

[0091] After completing the calibration of the response function of the receiving optical path to light of different frequencies, the light-emitting element to be tested is placed on the focal plane of the first microscope objective lens, the light-emitting element to be tested is lit by a power supply, and the light signal emitted by the light-emitting element to be tested is received by the receiving optical path. The first detection device measures the light intensity I of the light-emitting element to be tested. x (λ). The light signal that can be received by the device is Sx (λ)=I x (λ) / H(λ).

[0092] S6: According to formula S x (λ)=I x (λ) / H(λ), calculate and obtain the luminous spectrum intensity distribution S of the luminous element 4 to be tested x (λ).

[0093] S7: The third detection device 3 measures the current value of the light-emitting element 4 to be tested when it emits light.

[0094] S8: Based on the spectral intensity distribution S of the light emitting element 4 to be tested x (λ) and current value, and obtain the external quantum efficiency of the light-emitting element 4 to be tested.

[0095] Specifically, step S8 includes:

[0096] S81, obtaining the luminous spectrum intensity distribution of the luminous element to be tested at different angles and the receiving angle of the first microscope objective lens, and calculating and obtaining the real luminous spectrum intensity distribution of the luminous element to be tested.

[0097] By measuring, simulating, or directly using the luminous model of an ideal micro-luminescent element, the luminous intensity distribution model of the luminescent element to be tested at different angles is obtained, and the real luminous spectrum intensity distribution of the luminescent element to be tested is calculated according to the receiving angle of the first microscope objective lens.

[0098] Preferably, according to the spectral intensity distribution model of the light emitted by the light emitting element at different angles and the receiving angle of the first microscope objective lens, the actual spectral intensity distribution S of the light emitting device can be calculated. x0 (λ).

[0099] Specifically, in this embodiment, according to the spectral intensity distribution S of the light-emitting element 4 to be tested x (λ), and use the Lambertian distribution model to calculate the actual luminous spectrum intensity distribution S of the luminous element 4 to be tested x0 (λ).

[0100] S82, based on the calculated real luminous spectrum intensity distribution S of the luminous element 4 to be tested x0 (λ) and the measured current value, and calculate the external quantum efficiency of the light-emitting element 4 to be tested.

[0101] According to the luminous spectrum intensity distribution S of the light-emitting device x0 The external quantum efficiency of the light-emitting device to be tested can be calculated based on the current (λ) and the current passing through the light-emitting device to be tested.

[0102] In addition, according to the measured spectral intensity distribution S of the light-emitting element to be tested x0(λ), the optical parameters of the light-emitting device, such as luminous efficiency, luminous flux, luminous intensity, luminance (brightness), color coordinates, color temperature, main wavelength, peak wavelength, half-peak width, etc., can also be obtained, and the IVL curve can be obtained at the same time.

[0103] Second embodiment

[0104] Reference Figure 1 , Figure 2 and Figure 4 As shown, the external quantum efficiency detection system of the micro-area light-emitting element according to the embodiment of the present invention includes:

[0105] The calibration equipment includes a light source, a focusing element, a conducting element and a second detection device. The light source 21 is a white light LED light source, which provides a wide spectrum of light covering 380nm to 700nm from ultraviolet to visible. The focusing element is a second microscope objective lens, the rear end of the second microscope objective lens is aligned with the light source, the front end of the second microscope objective lens is aligned with the front end of the first microscope objective lens, and the focal planes of the first microscope objective lens and the second microscope objective lens coincide. The first microscope objective lens is coaxially arranged with the second microscope objective lens. The focusing element is used to receive the light from the light source and converge it on the focal plane of the first microscope objective lens. The conducting element is a transmission medium, air, and the transmittance T(λ) of air to light of different frequencies is 1 by default.

[0106] The receiving optical path includes a first microscope objective lens, a coupling member 13 and a first detection device 12. The first microscope objective lens of the receiving optical path adopts an independent optical path (it does not share a microscope objective lens with the second microscope objective lens). The first microscope objective lens is used to collect the optical signal on the focal plane of the first microscope objective lens. The first detection device is an imaging spectrometer, which is used to perform spectrum and intensity I (λ) detection on the optical signal received by the receiving optical path; the power supply 41, in this embodiment, is a source meter, which is used to provide power to the light-emitting element to be tested to light it up; the third detection device 3 is used to detect the current when the light-emitting element to be tested emits light; in this embodiment, the power supply and the third detection device are the same device, namely, a source meter.

[0107] In this embodiment, the detection method of the external quantum efficiency detection system of the micro-area light-emitting element of the embodiment of the present invention has the following steps:

[0108] S1: The light source 21 of the calibration device 2 emits light of different frequencies, and the second microscope objective lens of the calibration device 2 converges the light of different frequencies onto the focal plane at the front end of the first microscope objective lens 11 of the receiving optical path 1.

[0109] Specifically, the white light LED light source is output through the optical fiber and converges onto the focal plane of the first microscope lens through the second microscope lens.

[0110] S2: The second detection device 24 of the calibration device 2 measures the spectral intensity distribution S of the light of different frequencies converged on the focal plane of the first microscope objective 11 c (λ).

[0111] The optical signal gathered by the white light LED light source under the first microscope objective is collected and detected by a spectrum detection system with a cosine corrector calibrated with absolute irradiance as the receiving end.

[0112] At this time, the spectral intensity distribution S of the white light LED light source after passing through the focusing element can be obtained. c At this point, the spectral intensity calibration of the light of different frequencies output by the white light LED light source under the first microscope objective lens is completed.

[0113] S3: The conducting member 23 is air, so the broad spectrum light output by the white light LED light source is transmitted through the air into the front end of the first microscope objective lens 11, and the light of different frequencies is injected into the coupling member 13 of the receiving optical path 1 through the rear end of the first microscope objective lens 11 and then injected into the first detection device 12 of the receiving optical path 1 after coupling through the coupling member 13. The first detection device 12 measures the light intensity I of the injected broad spectrum light. c (λ).

[0114] S4: According to formula I c (λ) = S c (λ)×T(λ)×H(λ), calculate and obtain the response function H(λ) of the receiving optical path 1 to light of different frequencies.

[0115] According to I c (λ) = S c (λ)×T(λ)×H(λ), the response function H(λ) of the receiving optical path to light of different frequencies can be calculated, thus completing the calibration of the receiving optical path.

[0116] S5: The luminous element 4 to be tested is placed on the focal plane of the first microscope objective 11 and energized, so that the luminous element 4 to be tested emits light to generate incident light, and the incident light enters the front end of the first microscope objective 11 and is coupled by the coupling element 13 at the rear end of the first microscope objective 11 and then enters the first detection device 12. The first detection device 12 measures the light intensity I of the incident light. x (λ).

[0117] The light-emitting element to be tested is placed on the focal plane of the first microscope objective lens, the light-emitting element to be tested is lit by a power supply, and the light signal emitted by the light-emitting element to be tested is received by the receiving optical path. The first detection device measures the light intensity I of the light-emitting element to be tested. x (λ). The light signal that can be received by the device is S x (λ)=I x (λ) / H(λ).

[0118] S6: According to formula S x (λ)=I x(λ) / H(λ), calculate and obtain the luminous spectrum intensity distribution S of the luminous element 4 to be tested x (λ).

[0119] S7: The third detection device 3 measures the current value of the light-emitting element 4 to be tested when it emits light.

[0120] S8: Based on the spectral intensity distribution S of the light emitting element 4 to be tested x (λ) and current value, and obtain the external quantum efficiency of the light-emitting element 4 to be tested.

[0121] Specifically, step S8 includes:

[0122] S81, obtaining the luminous spectrum intensity distribution of the luminous element to be tested at different angles and the receiving angle of the first microscope objective lens, and calculating and obtaining the real luminous spectrum intensity distribution of the luminous element to be tested.

[0123] By measuring, simulating, or directly using the luminous model of an ideal micro-luminescent element, the luminous intensity distribution model of the luminescent element to be tested at different angles is obtained, and the real luminous spectrum intensity distribution of the luminescent element to be tested is calculated according to the receiving angle of the first microscope objective lens.

[0124] Preferably, according to the spectral intensity distribution model of the light emitted by the light emitting element at different angles and the receiving angle of the first microscope objective lens, the actual spectral intensity distribution S of the light emitting device can be calculated. x0 (λ).

[0125] Specifically, in this embodiment, according to the spectral intensity distribution S of the light-emitting element 4 to be tested x (λ), and use the Lambertian distribution model to calculate the actual luminous spectrum intensity distribution S of the luminous element 4 to be tested x0 (λ).

[0126] S82, based on the calculated real luminous spectrum intensity distribution S of the luminous element 4 to be tested x0 (λ) and the measured current value, and calculate the external quantum efficiency of the light-emitting element 4 to be tested.

[0127] In addition, according to the measured spectral intensity distribution S of the light-emitting element to be tested x0 (λ), the optical parameters of the light-emitting device, such as luminous efficiency, luminous flux, luminous intensity, luminance (brightness), color coordinates, color temperature, main wavelength, peak wavelength, half-peak width, etc., can also be obtained, and the IVL curve can be obtained at the same time.

[0128] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0129] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, some details in the embodiments should not be construed as limiting the present invention, and the present invention shall be protected by the scope defined by the attached claims.

Claims

1. A system for detecting the external quantum efficiency of a light-emitting element in a micro-area, characterized in that: include: A receiving optical path, comprising a first microscope objective lens for collecting incident light and a first detection device for measuring the light intensity of the incident light, wherein the first detection device is aligned with the rear end of the first microscope objective lens; A calibration device for obtaining the response function of the receiving optical path to incident light of different frequencies, comprising a light source for emitting light of different frequencies, a condenser for converging the light of different frequencies on a focal plane at the front end of the first microscope objective lens, a conductive member for guiding the light of different frequencies converged on the focal plane into the front end of the first microscope objective lens, and a second detection device for measuring the spectral intensity distribution of the light of different frequencies converged on the focal plane, wherein the first end of the condenser is aligned with the light source, the second end of the condenser is aligned with the focal plane, and the conductive member is arranged on the focal plane; as well as The third detection device is used to measure the current when the light-emitting element to be tested emits light.

2. The external quantum efficiency detection system of the micro-area light-emitting element according to claim 1, characterized in that: The receiving optical path further comprises a coupling member, the coupling member is aligned with the rear end of the first microscope objective lens, and the first detection device is aligned with the coupling member.

3. The external quantum efficiency detection system of the micro-area light-emitting element according to claim 1, characterized in that: The conductive member is a light-transmitting medium, the focusing member is a second microscope objective lens, the rear end of the second microscope objective lens is aligned with the light source, the front end of the second microscope objective lens is arranged opposite to the front end of the first microscope objective lens, and the focal plane of the second microscope objective lens coincides with the focal plane of the first microscope objective lens.

4. The external quantum efficiency detection system of the micro-area light-emitting element according to claim 1, characterized in that: The conductive member is a reflective element, the focusing member is a third microscope objective lens, the rear end of the third microscope objective lens is aligned with the light source, the front end of the third microscope objective lens is arranged opposite to the front end of the first microscope objective lens, and the focal plane of the third microscope objective lens, the focal plane of the first microscope objective lens and the reflective surface of the reflective element are all compared to a straight line.

5. The external quantum efficiency detection system of the micro-area light-emitting element according to claim 4, characterized in that: The focal plane of the third microscope objective lens, the focal plane of the first microscope objective lens and the reflective surface of the reflective element coincide with each other, and the first microscope objective lens and the third microscope objective lens are the same microscope objective lens.

6. The external quantum efficiency detection system of the micro-area light-emitting element according to claim 4, characterized in that: The reflective element is a specular reflective element or a diffuse reflective element.

7. The external quantum efficiency detection system of the micro-area light-emitting element according to claim 1, characterized in that: The first detection device is a photoelectric light intensity detection device.

8. The external quantum efficiency detection system of the micro-area light-emitting element according to claim 7, characterized in that: The photoelectric light intensity detection device is any one of a spectrometer, a brightness meter, a power meter, a CCD, a CMOS, a PMT, and a single photon detector.

9. A method for detecting the external quantum efficiency of a light-emitting element under a micro-area, characterized in that: The following steps are involved: The light source emits light of different frequencies and converges the light of different frequencies on the focal plane at the front end of the first microscope objective lens; Determining the spectral intensity distribution of the light of different frequencies focused on the focal plane; The conductive member is arranged on the focal plane, the conductive member guides the light of different frequencies into the front end of the first microscope objective lens, the light of different frequencies is emitted through the rear end of the first microscope objective lens, and the light intensity of the emitted light of different frequencies is measured; Calculating and obtaining the response function of the receiving optical path to light of different frequencies; Placing a light-emitting element to be tested on the focal plane and energizing the light-emitting element to be tested, so that the light-emitting element to be tested emits light to generate incident light, the incident light enters the front end of the first microscope objective lens and is emitted through the rear end of the first microscope objective lens, and the light intensity of the emitted incident light is measured; Calculating and obtaining the luminous spectrum intensity distribution of the luminous element to be tested; Determining the current value of the light-emitting element to be tested when it emits light; The external quantum efficiency of the light-emitting element to be tested is obtained.

10. The detection method according to claim 9, characterized in that: The step of obtaining the external quantum efficiency of the light-emitting element to be tested comprises: Acquire the luminous spectrum intensity distribution of the luminous element to be tested at different angles and the receiving angle of the first microscope objective lens to obtain the real luminous spectrum intensity distribution of the luminous element to be tested; The external quantum efficiency of the light-emitting element to be tested is obtained by calculation according to the actual luminous spectrum intensity distribution and the current value of the light-emitting element to be tested.

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