System and method for testing performance of electrically induced circularly polarized light-emitting device

Abstract

The invention relates to the technical field of optical performance testing, and discloses a system and a method for testing the performance of an electrically induced circularly polarized light-emitting device. The system integrates an electrical performance measurement module and an optical performance module, and continuously provides electrical signals required by testing for a to-be-tested circularly polarized light-emitting device through a source meter; the electrical signal is transmitted to the test terminal, so that electrical performance parameters of the to-be-tested circular polarization light-emitting device are determined according to the electrical signal, divergent photons of the to-be-tested circular polarization light-emitting device are collected through the first integrating sphere and transmitted to the first spectrograph, and light-emitting spectrum information of the to-be-tested circular polarization light-emitting device is obtained; the optical performance parameters of the to-be-tested circular polarization light-emitting device are determined through the test terminal according to the light-emitting spectrum information, so that the electrical performance measurement and the optical performance measurement of the circular polarization light-emitting device are integrated for synchronous measurement, and the situation that the later data calculation and processing process is too tedious is avoided.

Description

Technical Field

[0001] This invention relates to the field of optical performance testing technology, and in particular to a performance testing system and method for electro-polarized light-emitting devices. Background Technology

[0002] Circularly polarized light-emitting devices are core components of next-generation information technology, possessing revolutionary potential in fields such as quantum communication, 3D display, optical information encryption, and biomedicine. These devices, by directly emitting highly asymmetric circularly polarized light, can significantly improve data transmission security, display clarity, and biological imaging accuracy, meeting the technical demands for miniaturization, low power consumption, and multifunctional integration.

[0003] In existing performance testing of circularly polarized light-emitting devices, it is difficult to simultaneously measure the electrical and optical characteristics of the devices, resulting in an overly cumbersome process for subsequent data calculation and processing. Summary of the Invention

[0004] In view of this, the present invention provides a performance testing system and method for electro-polarized light-emitting devices, which solves the technical problem that it is difficult to simultaneously measure the electrical and optical characteristics of circularly polarized light-emitting devices in the performance testing of existing circularly polarized light-emitting devices, resulting in an overly cumbersome process for subsequent data calculation and processing.

[0005] The first aspect of this invention provides a performance testing system for an electro-polarized light-emitting device, comprising: an electrical performance measurement module, an optical performance module, and a testing terminal;

[0006] The electrical performance measurement module includes a source meter and a device fixture for holding the circularly polarized light-emitting device under test. The two sides of the source meter are respectively connected to the circularly polarized light-emitting device under test and the test terminal. The source meter is used to continuously provide the electrical signal required for testing to the circularly polarized light-emitting device under test, and to make the circularly polarized light-emitting device under test emit divergent photons. It is also used to transmit the electrical signal to the test terminal.

[0007] The optical performance module includes a first integrating sphere and a first spectrometer connected to the first integrating sphere; the first integrating sphere collects the divergent photons emitted by the circularly polarized light-emitting device under test and transmits them to the first spectrometer; the first spectrometer is used to detect the first spectral information of the divergent photons and transmit the first spectral information to the test terminal.

[0008] The test terminal is used to determine the electrical performance parameters and optical performance parameters of the circularly polarized light-emitting device under test based on the electrical signal and the first spectral information.

[0009] Preferably, the electrical signal includes a voltage signal and a current signal; the electrical performance parameters include a current density-voltage variation curve, a start-up voltage, and a voltage peak corresponding to the maximum brightness of the device;

[0010] The test terminal is used to determine the start-up voltage and the voltage peak corresponding to the maximum brightness of the device based on the voltage signal; it is also used to determine the current density of the circularly polarized light-emitting device under test based on the predetermined light-emitting area of ​​the circularly polarized light-emitting device under test and the current signal; and to determine the current density-voltage change curve based on the current density and the voltage signal.

[0011] Preferably, the optical performance parameters include a brightness-voltage variation curve;

[0012] The test terminal is used to determine the luminous brightness of the circularly polarized light-emitting device under test based on the first spectral information, and is also used to determine the brightness-voltage change curve based on the luminous brightness and the voltage signal.

[0013] Preferably, the optical performance parameters include the maximum external quantum efficiency;

[0014] The test terminal is used to determine the maximum external quantum efficiency based on the first spectral information and the current signal.

[0015] Preferably, the system further includes a circularly polarized optical path module; the optical performance module further includes a second integrating sphere and a second spectrometer connected to the second integrating sphere;

[0016] The circular polarization optical path module is used to split the divergent photons emitted by the circular polarization light-emitting device under test into first linearly polarized light and second linearly polarized light;

[0017] After passing through the first integrating sphere and the second integrating sphere, the first linearly polarized light and the second linearly polarized light are respectively transmitted to the first spectrometer and the second spectrometer.

[0018] The first spectrometer and the second spectrometer are respectively used to transmit the second spectral information and the third spectral information corresponding to the first linearly polarized light and the second linearly polarized light to the test terminal;

[0019] The testing terminal is used to determine the optical performance parameters of the circularly polarized light-emitting device under test based on the second spectral information and the third spectral information.

[0020] Preferably, the circularly polarized optical path module includes a collimating lens, a quarter-wave plate, a polarizing beam splitter, a converging lens, a converging lens, and a mounting base;

[0021] The collimating lens, the quarter-wave plate, and the polarizing beam splitter are arranged sequentially along the optical axis;

[0022] The converging lens is disposed on the reflected light path of the polarizing beam splitter and is positioned opposite to the second integrating sphere;

[0023] The converging lens is disposed on the refracting optical path of the polarizing beam splitter and is positioned opposite to the first integrating sphere;

[0024] The quarter-wave plate is mounted on the mounting base, and the quarter-wave plate is restricted to switch in a first direction or a second direction by rotating the mounting base.

[0025] Preferably, the optical performance parameters include an electroluminescence asymmetry factor; the second spectral information includes the luminous flux of the first linearly polarized light measured in the first direction and the luminous flux of the first linearly polarized light measured in the second direction; the third spectral information includes the luminous flux of the second linearly polarized light measured in the first direction and the luminous flux of the second linearly polarized light measured in the second direction.

[0026] The test terminal is used to determine the total linearly polarized light flux based on the first linearly polarized light flux measured in the first direction and the first linearly polarized light flux measured in the second direction; to determine the total linearly polarized light flux based on the second linearly polarized light flux measured in the first direction and the second linearly polarized light flux measured in the second direction; and to determine the electroluminescence asymmetry factor based on the total linearly polarized light flux of the first direction and the total linearly polarized light flux of the second direction.

[0027] Secondly, the present invention also provides a testing method applied to the performance testing system for electro-polarized light-emitting devices as described in the first aspect, the method comprising:

[0028] The source meter continuously provides the electrical signal required for testing to the circularly polarized light-emitting device under test, and causes the circularly polarized light-emitting device under test to emit divergent photons, and transmits the electrical signal to the test terminal.

[0029] The divergent photons emitted by the circularly polarized light-emitting device under test are collected by the first integrating sphere and transmitted to the first spectrometer. The first spectrometer detects the first spectral information of the divergent photons and transmits the first spectral information to the test terminal.

[0030] The testing terminal determines the electrical and optical performance parameters of the circularly polarized light-emitting device under test based on the electrical signal and the first spectral information.

[0031] Preferably, the electrical performance parameters include the current density-voltage variation curve, the start-up voltage, and the voltage peak corresponding to the maximum brightness of the device; the optical performance parameters include the brightness-voltage variation curve and the maximum external quantum efficiency.

[0032] Preferably, the electro-polarized circularly polarized light-emitting device performance testing system further includes a circularly polarized optical path module; the optical performance module further includes a second integrating sphere and a second spectrometer connected to the second integrating sphere; the method further includes:

[0033] The divergent photons emitted by the circularly polarized light-emitting device under test are split into first linearly polarized light and second linearly polarized light;

[0034] After passing through the first integrating sphere and the second integrating sphere, the first linearly polarized light and the second linearly polarized light are respectively transmitted to the first spectrometer and the second spectrometer.

[0035] The first spectrometer and the second spectrometer respectively transmit the second spectral information and the third spectral information corresponding to the first linearly polarized light and the second linearly polarized light to the test terminal;

[0036] The testing terminal determines the optical performance parameters of the circularly polarized light-emitting device under test based on the second spectral information and the third spectral information; wherein, the optical performance parameters include the electroluminescence asymmetry factor.

[0037] As can be seen from the above technical solution, this invention integrates the electrical performance measurement module and the optical performance module into one unit. A source meter continuously provides the electrical signal required for testing the circularly polarized light-emitting device under test (CPT), and the electrical signal is transmitted to the testing terminal. Based on the electrical signal, the electrical performance parameters of the CPT are determined. Furthermore, a first integrating sphere collects the divergent photons of the CPT and transmits them to a first spectrometer to obtain the emission spectrum information of the CPT. The testing terminal then determines the optical performance parameters of the CPT based on the emission spectrum information. This integrates the electrical and optical performance measurements of the CPT into a single, synchronous measurement, thus avoiding the overly cumbersome process of subsequent data calculation and processing. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1This is a first structural schematic diagram of a performance testing system for an electro-polarized light-emitting device provided in an embodiment of the present invention;

[0040] Figure 2 This is a schematic diagram of the second structure of a performance testing system for an electro-polarized light-emitting device provided in an embodiment of the present invention;

[0041] Figure 3 This is a schematic diagram of the first structure of a performance testing system for an electro-polarized light-emitting device after adding a circularly polarized optical path module, as provided in an embodiment of the present invention.

[0042] Figure 4 This is a schematic diagram of the second structure of a performance testing system for an electro-polarized light-emitting device after adding a circularly polarized optical path module, as provided in an embodiment of the present invention.

[0043] Figure 5 This is a schematic diagram of the optical path of a circularly polarized light-emitting module provided in an embodiment of the present invention.

[0044] Figure 6 An electroluminescence asymmetry factor curve is provided for an embodiment of the present invention;

[0045] Figure 7 A flowchart of a test method for a performance testing system for an electro-polarized light-emitting device provided in an embodiment of the present invention. Detailed Implementation

[0046] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] Unless otherwise specified or defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. When combined with the technical solutions of the invention in a real-world scenario, all technical and scientific terms used herein may also have meanings corresponding to the purpose of achieving the technical solutions of the invention. The terms "first," "second," etc., used herein are merely for distinguishing names and do not represent a specific number or order. The term "and / or," as used herein, includes any and all combinations of one or more of the associated listed items.

[0048] It should be noted that when a component is considered "fixed" to another component, it can be directly fixed to the other component or there can be an intervening component; when a component is considered "connected" to another component, it can be directly connected to the other component or there can be an intervening component; when a component is considered "mounted" on another component, it can be directly mounted on the other component or there can be an intervening component; when a component is considered "placed" on another component, it can be directly placed on the other component or there can be an intervening component.

[0049] Unless otherwise specified or defined, the terms "described" or "the" as used herein refer to the technical features or technical content mentioned or described prior to the relevant section, which may be the same as or similar to the technical features or technical content mentioned herein. Furthermore, the terms "comprising" and "having," and any variations thereof, as used herein, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or apparatus.

[0050] like Figure 1 and Figure 2 As shown, this application provides a performance testing system for an electro-polarized light-emitting device, including: an electrical performance measurement module 1, an optical performance module 3, and a testing terminal 4;

[0051] The electrical performance measurement module 1 includes a source meter 101 and a device fixture 102 for holding the circularly polarized light-emitting device under test (not shown). The two sides of the source meter 101 are connected to the circularly polarized light-emitting device under test and the test terminal 4, respectively. The source meter 101 is used to continuously provide the electrical signal required for the test to the circularly polarized light-emitting device under test, and to make the circularly polarized light-emitting device under test emit divergent photons. It is also used to transmit the electrical signal to the test terminal 4.

[0052] The source meter 101 can precisely control the intensity and stability of the provided electrical signal to ensure the accuracy and reliability of the test results. The device fixture 102 securely holds the circularly polarized light-emitting device under test and can control the light-emitting position of the device, which can ensure the stability and consistency of the device during the test and further improve the accuracy of the test.

[0053] Taking the Keithley 2450 source meter as an example, the positive and negative terminals of the source meter 101 can be connected to the device fixture 102 by wiring. By designing the device fixture 102, the positive and negative terminals of the circularly polarized light-emitting device under test can be connected, thereby causing the device to light up. At the same time, the Keithley 2450 source meter is connected to the test terminal 4, and the test terminal 4 can directly read the voltage and current information transmitted from the source meter 101.

[0054] The optical performance module 3 includes a first integrating sphere 302 and a first spectrometer 304 connected to the first integrating sphere 302; the first integrating sphere 302 collects the divergent photons emitted by the circularly polarized light-emitting device under test and transmits them to the first spectrometer 304; the first spectrometer 304 is used to detect the first spectral information of the divergent photons and transmit the first spectral information to the test terminal 4.

[0055] Among them, the first integrating sphere 302 has high internal reflection performance, which can effectively collect and converge divergent photons emitted by the circularly polarized light-emitting device under test, reduce photon loss, and improve the detection accuracy of spectral information. At the same time, the first spectrometer 304 has the characteristics of high sensitivity and high resolution, which can accurately detect and record the spectral information of divergent photons, providing reliable data support for the test terminal 4.

[0056] In a typical example, the first integrating sphere 302 is connected to the first spectrometer 304 via an optical fiber bundle.

[0057] Test terminal 4 is used to determine the electrical and optical performance parameters of the circularly polarized light-emitting device under test based on the electrical signal and the first spectral information.

[0058] Test terminal 4 can be a computer, or other terminals or servers with the computing power required for electrical and optical performance, etc., without any restrictions.

[0059] To measure the electrical and optical performance parameters of the circularly polarized light-emitting device (EPD), the EPD is first placed on the device fixture 102. A source meter 101 is connected to continuously supply an electrical signal (voltage) to the device. When a certain voltage is reached, the EPD emits light. As the voltage is increased further, the brightness of the EPD gradually increases until the device is damaged. Simultaneously, the source meter is connected to a computer, allowing the computer software to read current and voltage information. A first spectrometer 304 is also connected to the computer, allowing the computer software to read emission spectrum information. The electrical performance parameters of the EPD can be determined using the current and voltage information, and the optical performance parameters can be determined using the emission spectrum information.

[0060] In the application of circularly polarized light-emitting devices under test, their electrical and optical performance parameters are crucial, as they directly reflect the device's performance. The testing system provided by this invention allows for comprehensive and accurate measurement of these key parameters, providing strong technical support for the research, development, production, and application of these devices.

[0061] It should be noted that in traditional methods, the circularly polarized light-emitting device under test (CPT) is typically placed on a spectrometer to measure its electroluminescence spectrum before being connected to a source meter to measure its electrical properties. This embodiment integrates the electrical performance measurement module and the optical performance module. The source meter continuously provides the necessary electrical signals to the CPT, and these signals are transmitted to a testing terminal to determine the CPT's electrical performance parameters. Furthermore, a first integrating sphere collects the divergent photons from the CPT and transmits them to a first spectrometer to obtain the CPT's emission spectrum information. The testing terminal then determines the CPT's optical performance parameters based on this emission spectrum information. This integrated measurement of the CPT's electrical and optical properties allows for simultaneous measurement, avoiding the overly cumbersome subsequent data calculation and processing.

[0062] The following description is as follows: Figure 1 and Figure 2 Based on the structure shown, a detailed process is described for testing the electrical and optical performance parameters of the circularly polarized light-emitting device under test.

[0063] In some embodiments, the electrical signal includes a voltage signal and a current signal; the electrical performance parameters include the current density-voltage variation curve, the start-up voltage, and the voltage peak corresponding to the maximum brightness of the device.

[0064] The current density-voltage curve describes how the current density flowing through the circularly polarized light-emitting device under test changes under different voltages. This parameter reflects the device's conductivity and charge injection efficiency, and is one of the important indicators for evaluating device performance.

[0065] The start-up voltage refers to the minimum voltage required for the circularly polarized light-emitting device under test to start emitting light, and it reflects the ease or difficulty of starting the device.

[0066] The peak voltage corresponding to the maximum brightness of the device is the voltage value corresponding to the maximum brightness of the device within a given voltage range. This parameter helps to understand the voltage requirements of the device under high brightness operating conditions.

[0067] In this case, test terminal 4 is used to determine the start-up voltage and the voltage peak corresponding to the maximum brightness of the device based on the voltage signal.

[0068] In practical applications, the activation voltage can be determined by gradually increasing the voltage and observing whether the device begins to emit light. The peak voltage corresponding to the device's maximum brightness, however, requires adjusting the voltage to find the point where the device's brightness reaches its maximum, while ensuring device safety. These values ​​can be automatically obtained using computer software to capture the voltage signal.

[0069] The test terminal 4 is also used to determine the current density of the circularly polarized light-emitting device under test based on the predetermined emitting area and current signal of the device; and to determine the current density-voltage change curve based on the current density and voltage signal.

[0070] The predetermined emitting area of ​​the circularly polarized light-emitting device under test is determined during the fabrication of the device. It has a specific emitting position, and the area of ​​this emitting position is fixed.

[0071] In practical applications, by measuring and recording the current values ​​under different voltages and combining them with the light-emitting area of ​​the device, the corresponding current density can be calculated, thereby plotting the current density-voltage change curve, i.e., the JV curve.

[0072] In some embodiments, the optical performance parameters include a brightness-voltage variation curve.

[0073] The brightness-voltage variation curve describes how the luminous brightness of the circularly polarized light-emitting device under test changes under different voltages. This parameter can intuitively reflect the luminous efficiency and stability of the device and is one of the important indicators for evaluating the optical performance of the device.

[0074] In this case, the test terminal 4 is used to determine the luminous brightness of the circularly polarized light-emitting device under test based on the first spectral information, and also to determine the brightness-voltage change curve based on the luminous brightness and voltage signal.

[0075] The first spectral information includes the radiant flux entering the first integrating sphere. The luminous intensity of the circularly polarized light-emitting device under test is determined as follows:

[0076]

[0077] In the formula, L represents the luminous intensity. For maximum spectral light efficiency, it is a constant. =638lm / W, The radiation flux entering the first integrating sphere. The photopic spectral luminous efficiency function is defined based on experimental values. The light-emitting area of ​​the device, λ is the wavelength.

[0078] After obtaining the luminance of the circularly polarized light-emitting device, the test terminal 4 can further plot the luminance-voltage variation curve, i.e., the LV curve, based on the luminance and voltage signal. This curve clearly shows the trend of the device's luminance variation under different voltage driving conditions, providing an important basis for evaluating the device's luminous efficiency and stability.

[0079] In some embodiments, optical performance parameters include maximum external quantum efficiency.

[0080] The maximum external quantum efficiency (MPE) describes the efficiency with which a circularly polarized light-emitting device (EPD) converts injected electrons into outwardly radiated photons. It is a key indicator of a device's luminous efficiency. High MPE means that the device can more effectively convert electrical energy into light energy, thereby improving luminous efficiency and reducing energy consumption.

[0081] Test terminal 4 is used to determine the maximum external quantum efficiency based on the first spectral information and the current signal.

[0082] The calculation process for the maximum external quantum efficiency is as follows:

[0083]

[0084] In the formula, For maximum external quantum efficiency, , They represent the number of photons and electrons, respectively; I represents the device injection current; e represents the charge of a single electron; h is Planck's constant; and c is the speed of light.

[0085] The electroluminescence asymmetry factor is a key dimensionless parameter for quantitatively characterizing the degree of chirality (i.e., the difference in intensity between the left-hand and right-hand circularly polarized light emitted by a material. It is defined as twice the ratio of the difference between the intensity of the left-hand circularly polarized light (IL) and the intensity of the right-hand circularly polarized light (IR) emitted by the light-emitting device to the sum of the two.

[0086] Furthermore, in the prior art, the inventors have discovered that existing measurement systems for measuring the electroluminescence asymmetry factor require testing the luminescence intensity / luminance of the device under different circular polarization states under both left-handed and right-handed filtering conditions. Due to the attenuation of the device's luminescence intensity during the testing process and the presence of numerous artifacts, the measurement data becomes extremely inaccurate. Firstly, neither traditional measurement methods nor commercially available measuring instruments (Jasco CPL-300) can resolve the artifacts in the electroluminescence asymmetry factor measurement caused by the attenuation of the device's luminescence intensity / luminance over testing time. Although commercial measuring instruments (such as the Jasco CPL-300) use photoelastic modulators to improve measurement accuracy, this method still sacrifices measurement time, typically requiring several minutes or even more than ten minutes. The instability of the device's luminous brightness severely affects the comparison of the intensity / luminous brightness of left-handed and right-handed circularly polarized light, thus leading to a decrease in measurement accuracy. Secondly, the traditional method for measuring luminous devices is to measure the asymmetry factor using a quarter-wave plate and a linear polarizer. This method usually requires manual rotation of the quarter-wave plate, and the rotation angle often deviates from the expected value, resulting in very limited measurement accuracy. Finally, in addition to the obvious artifacts mentioned above, there are also artifacts such as spectrometer measurement bias and circular dichroism absorption of optical elements (different absorption intensities for left-handed and right-handed circularly polarized light).

[0087] Artifacts refer to non-real signals appearing in measurement results or images. These signals do not originate from the actual physical characteristics of the target sample or the object being measured, but are false information introduced by defects in the measurement system itself, environmental interference, or data processing errors.

[0088] Furthermore, regarding the synchronization of electrical and optical characteristics measurements of circularly polarized light-emitting devices, neither of the two methods mentioned above can simultaneously measure both electrical and optical characteristics, resulting in an overly cumbersome process for subsequent data calculation and processing.

[0089] Therefore, the process of measuring the electroluminescence asymmetry factor in the embodiments of this application is described below.

[0090] like Figure 3 and Figure 4 As shown, in Figure 1 and Figure 2 Based on the performance testing system of the electro-polarized circularly polarized light-emitting device, a circularly polarized optical path module 2 is added; the optical performance module 3 also includes a second integrating sphere 301 and a second spectrometer 303 connected to the second integrating sphere 301.

[0091] The circular polarization optical path module 2 is used to split the divergent photons emitted by the circularly polarized light-emitting device under test into first linearly polarized light and second linearly polarized light;

[0092] The first linearly polarized light and the second linearly polarized light are transmitted to the first spectrometer 304 and the second spectrometer 303 respectively after passing through the first integrating sphere 302 and the second integrating sphere 301.

[0093] The first spectrometer 304 and the second spectrometer 303 are respectively used to transmit the second spectral information and the third spectral information corresponding to the first linearly polarized light and the second linearly polarized light to the test terminal 4.

[0094] Test terminal 4 is used to determine the optical performance parameters of the circularly polarized light-emitting device under test based on the second spectral information and the third spectral information.

[0095] The circular polarization optical path module 2 includes a collimating lens 201, a quarter-wave plate 202, a polarizing beam splitter 203, a converging lens 204, a converging lens 205, and a mounting base (not shown).

[0096] The collimating lens 201, the quarter-wave plate 202, and the polarizing beam splitter 203 are arranged sequentially along the optical axis;

[0097] The converging lens 204 is disposed on the reflected light path of the polarizing beam splitter 203 and is positioned opposite to the second integrating sphere 301;

[0098] The converging lens 205 is disposed on the refracting optical path of the polarizing beam splitter 203 and is positioned opposite to the first integrating sphere 302;

[0099] A quarter-wave plate 202 is mounted on a mounting base, and the quarter-wave plate 202 is restricted to switching in a first direction or a second direction by rotating the mounting base.

[0100] In such Figure 3 and Figure 4 Based on the structure shown, the optical performance parameters include the electroluminescence asymmetry factor; the second spectral information includes the luminous flux of the first linearly polarized light measured in the first direction and the luminous flux of the first linearly polarized light measured in the second direction; the third spectral information includes the luminous flux of the second linearly polarized light measured in the first direction and the luminous flux of the second linearly polarized light measured in the second direction.

[0101] The test terminal 4 is used to determine the total luminous flux of the first linearly polarized light based on the luminous flux of the first linearly polarized light measured in the first direction and the luminous flux of the first linearly polarized light measured in the second direction; to determine the total luminous flux of the second linearly polarized light based on the luminous flux of the second linearly polarized light measured in the first direction and the luminous flux of the second linearly polarized light measured in the second direction; and to determine the electroluminescence asymmetry factor based on the total luminous flux of the first linearly polarized light and the total luminous flux of the second linearly polarized light.

[0102] For example, such as Figure 5As shown, the divergent photons (circularly polarized light) emitted by the circularly polarized light-emitting device under test first pass through the collimating lens 201 and become parallel circularly polarized light. Then, they pass through the quarter-wave plate 202 (at this time, the quarter-wave plate 202 is located in the first direction, i.e., the fast axis direction is at +45° with the ground plane). The left-hand circularly polarized light becomes perpendicular linearly polarized light (s-polarized light), and the right-hand circularly polarized light becomes parallel linearly polarized light (p-polarized light). Then, they pass through the polarizing beam splitter prism 203, where the s-polarized light is reflected and the p-polarized light is transmitted. Finally, the two linearly polarized lights pass through the converging lens 205 and the converging lens 204 respectively and enter the first integrating sphere 302 and the second integrating sphere 301, where they are detected by the first spectrometer 304 and the second spectrometer 303 respectively, to obtain the measured luminous flux Φ of the first linearly polarized light in the first direction. L+ The second linearly polarized light flux Φ measured in the first direction R+ .

[0103] The quarter-wave plate 202 is switched to the second direction again by rotating the mounting base, so that its fast axis is at -45° to the ground plane. At this time, when the circularly polarized light from the circularly polarized light-emitting device passes through the quarter-wave plate, the left-hand circularly polarized light becomes parallel linearly polarized light (p-polarized light), and the right-hand circularly polarized light becomes perpendicular linearly polarized light (s-polarized light). After passing through the polarizing beam splitter prism 203, the s-polarized light is reflected, while the p-polarized light is transmitted. Finally, both linearly polarized lights enter the integrating sphere and are detected by the spectrometer, yielding the measured luminous flux Φ of the first linearly polarized light in the second direction. L- The second linearly polarized light flux Φ measured in the second direction R- .

[0104] The rotary mount can be a THORLABS motorized rotary mount, which greatly improves the rotation accuracy compared to manually rotating the quarter-wave plate.

[0105] The first linearly polarized light flux Φ measured when passing through the first direction L+ The first linearly polarized light flux Φ measured in the second direction L- The summation yields the total luminous flux Φ of the first linearly polarized light. L , that is Φ L =Φ L+ +Φ L- .

[0106] The luminous flux Φ of the second linearly polarized light measured when passing through the first direction R+ The second linearly polarized light flux Φ measured in the second direction R- The summation yields the total luminous flux Φ of the second linearly polarized light. R , that is Φ R =Φ R+ +Φ R- .

[0107] Then, the following formula is used in computer software for calculation:

[0108]

[0109] In the formula, It represents the electroluminescence asymmetry factor.

[0110] In practical numerical readings, the spectrometer typically reads the luminous flux at different wavelengths, resulting in an electroluminescence curve with wavelength on the x-axis and luminous flux on the y-axis. Here, we usually take the value of the y-axis as Φ, so the final calculated electroluminescence asymmetry factor is also usually a curve with wavelength on the x-axis and electroluminescence asymmetry factor on the y-axis, as shown below. Figure 6 As shown.

[0111] It should be noted that by measuring the luminous flux of left-handed and right-handed circularly polarized light twice, artifacts caused by brightness variations in the circularly polarized light-emitting device are effectively compensated. Traditional methods measure the electroluminescence asymmetry factor using a quarter-wave plate and a linear polarizer. This method suffers from artifacts because the brightness of the circularly polarized light-emitting device is unstable, leading to significant differences between the measured luminous flux of the left-handed and right-handed circularly polarized light. Compared to using a PEM instead of a quarter-wave plate, this invention also avoids artifacts caused by brightness variations in the circularly polarized light-emitting device due to excessively long measurement times.

[0112] Based on the same inventive concept, this application also provides a test method for implementing the above-mentioned electro-polarized light-emitting device performance test system.

[0113] The solution provided by this system is similar to the solution described in the above method. Therefore, the specific limitations of the test method embodiments of one or more electro-polarized light-emitting device performance testing systems provided below can be found in the limitations of the electro-polarized light-emitting device performance testing system described above, and will not be repeated here.

[0114] like Figure 7 As shown, this application provides a testing method for a performance testing system of an electro-polarized light-emitting device as described in any of the above embodiments. The method includes:

[0115] Step 100: Continuously provide the electrical signal required for testing to the circularly polarized light-emitting device under test through the source meter, and make the circularly polarized light-emitting device under test emit divergent photons, and transmit the electrical signal to the test terminal.

[0116] Step 200: Collect the divergent photons emitted by the circularly polarized light-emitting device under test through the first integrating sphere and transmit them to the first spectrometer. Detect the first spectral information of the divergent photons through the first spectrometer and transmit the first spectral information to the test terminal.

[0117] Step 300: The test terminal determines the electrical performance parameters and optical performance parameters of the circularly polarized light-emitting device under test based on the electrical signal and the first spectral information.

[0118] In some embodiments, the electrical performance parameters include the current density-voltage variation curve, the start-up voltage, and the voltage peak corresponding to the maximum brightness of the device; the optical performance parameters include the brightness-voltage variation curve and the maximum external quantum efficiency.

[0119] In this case, the test terminal determines the start-up voltage and the peak voltage corresponding to the maximum brightness of the device based on the voltage signal.

[0120] The current density of the circularly polarized light-emitting device under test is determined based on the predetermined emitting area and current signal of the device.

[0121] Based on the current density and voltage signals, determine the current density-voltage change curve.

[0122] The test terminal determines the luminous intensity of the circularly polarized light-emitting device under test based on the first spectral information, and determines the brightness-voltage change curve based on the luminous intensity and voltage signal.

[0123] The test terminal determines the maximum external quantum efficiency based on the first spectral information and the current signal.

[0124] In some embodiments, the electroluminescent circularly polarized light-emitting device performance testing system further includes a circularly polarized optical path module; the optical performance module further includes a second integrating sphere and a second spectrometer connected to the second integrating sphere; the method further includes:

[0125] The divergent photons emitted by the circularly polarized light-emitting device under test are split into first linearly polarized light and second linearly polarized light;

[0126] The first linearly polarized light and the second linearly polarized light are transmitted to the first spectrometer and the second spectrometer respectively after passing through the first integrating sphere and the second integrating sphere.

[0127] The first spectrometer and the second spectrometer respectively transmit the second spectral information and the third spectral information corresponding to the first linearly polarized light and the second linearly polarized light to the test terminal;

[0128] The test terminal 4 determines the optical performance parameters of the circularly polarized light-emitting device under test based on the second and third spectral information; among which, the optical performance parameters include the electroluminescence asymmetry factor.

[0129] The circular polarization optical path module 2 includes a collimating lens 201, a quarter-wave plate 202, a polarizing beam splitter 203, a converging lens 204, a converging lens 205, and a mounting base.

[0130] The collimating lens 201, the quarter-wave plate 202, and the polarizing beam splitter 203 are arranged sequentially along the optical axis;

[0131] The converging lens 204 is disposed on the reflected light path of the polarizing beam splitter 203 and is positioned opposite to the second integrating sphere 301;

[0132] The converging lens 205 is disposed on the refracting optical path of the polarizing beam splitter 203 and is positioned opposite to the first integrating sphere 302;

[0133] A quarter-wave plate 202 is mounted on a mounting base, and the quarter-wave plate 202 is restricted to switching in a first direction or a second direction by rotating the mounting base.

[0134] The second spectral information includes the luminous flux of the first linearly polarized light measured in the first direction and the luminous flux of the first linearly polarized light measured in the second direction; the third spectral information includes the luminous flux of the second linearly polarized light measured in the first direction and the luminous flux of the second linearly polarized light measured in the second direction.

[0135] In this case, the test terminal 4 determines the total linear polarization light flux based on the first linear polarization light flux measured in the first direction and the first linear polarization light flux measured in the second direction.

[0136] The total luminous flux of the second linearly polarized light is determined based on the luminous flux of the second linearly polarized light measured in the first direction and the luminous flux of the second linearly polarized light measured in the second direction.

[0137] The electroluminescence asymmetry factor is determined based on the total luminous flux of the first and second linearly polarized light.

[0138] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A performance testing system for an electro-polarized light-emitting device, characterized in that, include: Electrical performance measurement module (1), optical performance module (3) and test terminal (4); The electrical performance measurement module (1) includes a source meter (101) and a device fixture (102) for holding the circularly polarized light-emitting device under test. The two sides of the source meter (101) are respectively connected to the circularly polarized light-emitting device under test and the test terminal (4). The source meter (101) is used to continuously provide the electrical signal required for the test to the circularly polarized light-emitting device under test, and to make the circularly polarized light-emitting device under test emit divergent photons. It is also used to transmit the electrical signal to the test terminal (4). The optical performance module (3) includes a first integrating sphere (302) and a first spectrometer (304) connected to the first integrating sphere (302); the first integrating sphere (302) collects the divergent photons emitted by the circularly polarized light-emitting device under test and transmits them to the first spectrometer (304); the first spectrometer (304) is used to detect the first spectral information of the divergent photons and transmit the first spectral information to the test terminal (4). The test terminal (4) is used to determine the electrical performance parameters and optical performance parameters of the circularly polarized light-emitting device under test based on the electrical signal and the first spectral information.

2. The performance testing system for electro-polarized light-emitting devices according to claim 1, characterized in that, The electrical signals include voltage signals and current signals; the electrical performance parameters include current density-voltage variation curves, start-up voltage, and voltage peak value corresponding to the maximum brightness of the device. The test terminal (4) is used to determine the start-up voltage and the voltage peak corresponding to the maximum brightness of the device based on the voltage signal; it is also used to determine the current density of the circularly polarized light-emitting device under test based on the predetermined light-emitting area of ​​the circularly polarized light-emitting device under test and the current signal; and to determine the current density-voltage change curve based on the current density and the voltage signal.

3. The performance testing system for electro-polarized light-emitting devices according to claim 2, characterized in that, The optical performance parameters include the brightness-voltage variation curve; The test terminal (4) is used to determine the luminous brightness of the circularly polarized light-emitting device under test based on the first spectral information, and is also used to determine the brightness-voltage change curve based on the luminous brightness and the voltage signal.

4. The performance testing system for electro-polarized light-emitting devices according to claim 1, characterized in that, The optical performance parameters include the maximum external quantum efficiency; The test terminal (4) is used to determine the maximum external quantum efficiency based on the first spectral information and the current signal.

5. The performance testing system for electro-polarized light-emitting devices according to claim 1, characterized in that, The system also includes a circularly polarized optical path module (2); the optical performance module (3) also includes a second integrating sphere (301) and a second spectrometer (303) connected to the second integrating sphere (301); The circular polarization optical path module (2) is used to split the divergent photons emitted by the circular polarization light-emitting device under test into first linear polarization light and second linear polarization light; After passing through the first integrating sphere (302) and the second integrating sphere (301), the first linearly polarized light and the second linearly polarized light are respectively transmitted to the first spectrometer (304) and the second spectrometer (303). The first spectrometer (304) and the second spectrometer (303) are respectively used to transmit the second spectral information and the third spectral information corresponding to the first linearly polarized light and the second linearly polarized light to the test terminal (4); The test terminal (4) is used to determine the optical performance parameters of the circularly polarized light-emitting device under test based on the second spectral information and the third spectral information.

6. The performance testing system for electro-polarized light-emitting devices according to claim 5, characterized in that, The circular polarization optical path module (2) includes a collimating lens (201), a quarter-wave plate (202), a polarizing beam splitter (203), a converging lens (204), a converging lens (205), and a mounting base; The collimating lens (201), the quarter-wave plate (202), and the polarizing beam splitter (203) are arranged sequentially along the optical axis; The converging lens (204) is disposed on the reflected light path of the polarizing beam splitter (203) and is disposed opposite to the second integrating sphere (301); The converging lens (205) is disposed on the refracting optical path of the polarizing beam splitter (203) and is disposed opposite to the first integrating sphere (302); The quarter-wave plate (202) is mounted on the mounting base, and the quarter-wave plate (202) is restricted to switch in a first direction or a second direction by rotating the mounting base.

7. The performance testing system for electro-polarized light-emitting devices according to claim 6, characterized in that, The optical performance parameters include the electroluminescence asymmetry factor; the second spectral information includes the luminous flux of the first linearly polarized light measured in the first direction and the luminous flux of the first linearly polarized light measured in the second direction; the third spectral information includes the luminous flux of the second linearly polarized light measured in the first direction and the luminous flux of the second linearly polarized light measured in the second direction. The test terminal (4) is used to determine the total light flux of the first linearly polarized light based on the light flux of the first linearly polarized light measured in the first direction and the light flux of the first linearly polarized light measured in the second direction; to determine the total light flux of the second linearly polarized light based on the light flux of the second linearly polarized light measured in the first direction and the light flux of the second linearly polarized light measured in the second direction; and to determine the electroluminescence asymmetry factor based on the total light flux of the first linearly polarized light and the total light flux of the second linearly polarized light.

8. A test method applied to the performance testing system of the electro-polarized light-emitting device according to any one of claims 1 to 7, characterized in that, The method includes: The source table (101) continuously provides the electrical signal required for testing to the circularly polarized light-emitting device under test, and causes the circularly polarized light-emitting device under test to emit divergent photons, and transmits the electrical signal to the test terminal (4). The divergent photons emitted by the circularly polarized light-emitting device under test are collected by the first integrating sphere (302) and transmitted to the first spectrometer (304). The first spectrometer (304) detects the first spectral information of the divergent photons and transmits the first spectral information to the test terminal (4). The test terminal (4) determines the electrical performance parameters and optical performance parameters of the circularly polarized light-emitting device under test based on the electrical signal and the first spectral information.

9. The test method of the performance testing system for electro-polarized light-emitting devices according to claim 8, characterized in that, The electrical performance parameters include the current density-voltage variation curve, the start-up voltage, and the voltage peak corresponding to the maximum brightness of the device; the optical performance parameters include the brightness-voltage variation curve and the maximum external quantum efficiency.

10. The test method of the electro-polarized circularly polarized light-emitting device performance testing system according to claim 8, wherein the electro-polarized circularly polarized light-emitting device performance testing system further includes a circularly polarized optical path module (2); the optical performance module (3) further includes a second integrating sphere (301) and a second spectrometer (303) connected to the second integrating sphere (301); characterized in that, The method further includes: The divergent photons emitted by the circularly polarized light-emitting device under test are split into first linearly polarized light and second linearly polarized light; After passing through the first integrating sphere (302) and the second integrating sphere (301), the first linearly polarized light and the second linearly polarized light are respectively transmitted to the first spectrometer (304) and the second spectrometer (303). The first spectrometer (304) and the second spectrometer (303) respectively transmit the second spectral information and the third spectral information corresponding to the first linearly polarized light and the second linearly polarized light to the test terminal (4); The test terminal (4) determines the optical performance parameters of the circularly polarized light-emitting device under test based on the second spectral information and the third spectral information; wherein the optical performance parameters include the electroluminescence asymmetry factor.

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