232results about "Diode testing" patented technology

The invention provides a wafer detector, a preparation method thereof and a wafer detection circuit, which can be applied to the technical field of wafer detection. The wafer detector comprises a substrate; the plurality of pairs of electrodes are arranged on the substrate along a first direction; wires respectively led out from each of the plurality of pairs of electrodes on the substrate; a cilia structure is arranged on each electrode in the plurality of pairs of electrodes, a conductive layer electrically connected with the corresponding electrode is arranged on the surface of the cilia structure, and when the cilia structure sweeps the electrode to be detected in the MicroLED wafer from the side direction of the electrode to be detected in the second direction, the conductive layer is electrically connected with the electrode to be detected. The cilia structure has rigidity, so that the cilia structure is in electric contact with the to-be-detected electrode through deformation. When the wafer detector is used for detecting the to-be-detected MicroLED wafer, the wafer detector does not need to be pressed down and lifted up repeatedly, and the to-be-detected MicroLED wafer can be measured at a high speed through horizontal movement only by aligning at an initial position once.

The present disclosure provides an automated repair of LED substrates system in which an automated repair inspection module is used to determine the quality of incoming processing material an automated repair process module is used to process the processing material, an automated repair post-process module is used to inspect the resultant process material for acceptability, and an automated repair historical module is used to analyze the post process results of the most recent process, against all historical data to find enhanced process changes in the automated repair process module, and an automated repair integration module to update the automated repair process module based upon the results of the automated repair historical module.

Performance evaluation and structural optimization methods for a high-power semiconductor laser chip, and a performance evaluation system for a high-power semiconductor laser chip. The performance evaluation method for a high-power semiconductor laser chip comprises: providing a window on an N-side electrode of a chip to be tested (step 1); keeping the chip in an operating state (step 2); allowing a quantum well active region of the chip to generate spontaneous emission, so that the spontaneous emission is imaged outside the chip (step 3); acquiring, by means of a spectrograph, a spectrum of the spontaneous emission outside the chip and obtaining a two-dimensional distribution of a quantum well temperature of the chip in the operating state; and acquiring, by means of a CCD camera, an image of the spontaneous emission imaging outside the chip and obtaining a two-dimensional distribution of charge carriers in the quantum well of the chip in the operating state (step 4). According to the performance evaluation and structural optimization methods for a high-power semiconductor laser chip, the distributions of the temperature and the charge carrier concentration in the quantum well of the chip to be tested in the operating state in which the resolution is freely adjusted can be obtained. Operations of the methods are convenient, and implementation is simple and easy, thereby efficiently improving the accuracy of an evaluation result.

The present application provides a method for performance evaluation and structure optimization of a high-power semiconductor laser chip, and a system for performance evaluation. Wherein the method for performance evaluation of a high-power semiconductor laser chip comprises: setting a window in an N-surface electrode of a chip to be tested; maintaining the chip to be tested in an operating state, wherein spontaneous radiation is generated in an active area of a quantum well of the chip to be tested; imaging the spontaneous radiation at a position outside the chip to be tested; acquiring, by using a spectrometer outside the chip to be tested, a spectrum of the spontaneous radiation to obtain a two-dimensional distribution of temperature of the quantum well of the chip to be tested in the operating state; and acquiring, by using a CCD camera outside the chip to be tested, an image of the spontaneous radiation to obtain a two-dimensional distribution of carriers in the quantum well of the chip to be tested in the operating state. The method for performance evaluation and structure optimization of a high-power semiconductor laser chip provided by the present application can get the temperature distribution and the carrier concentration distribution of the chip to be tested in the operating state with a resolution that is freely adjustable, the operation is convenient and easy to implement, and the accuracy of evaluation results is effectively improved.

Proposed are a test device and a manufacturing method of the test device capable of testing a test object that is provided with an electrode which has a size and / or a pitch distance ranging from 1 to 100 micrometers (μm).

The present teachings relate to a method for identifying reusable components of a vehicle lamp assembly, the method including: i) performing an electric circuit functionality test on each component of a plurality of components of the vehicle lamp assembly; ii) performing an illumination test on each light source within the vehicle lamp assembly; iii) identifying which of the components of the plurality of components pass and / or fail the electric circuit functionality test; and iv) identifying which light sources pass and / or fail the illumination test.

The invention discloses a femtosecond pulse laser modulation-based GaN-based micro light-emitting diode test system, which comprises a femtosecond pulse laser excitation module, a first detection light path, a to-be-tested GaN-based micro light-emitting diode, a photovoltage detection and bias control module, a photoluminescence detection module and a control module, the control module is configured to control the excitation power and the external bias voltage of the femtosecond pulse laser excitation module, and synchronously collect a photoluminescence spectrum signal and a photovoltage signal; according to the excitation power, the external bias voltage, the photoluminescence spectrum signal and the photovoltage signal, the competition relation between carrier drift extraction and local radiation recombination under different bias electric field conditions is obtained, and therefore an experimental basis is provided for structural design and working bias optimization of the GaN-based micro light-emitting diode device to be tested.

Implementations described herein are related to a diode driver that recirculates residual current from an operating current pulse in an inductor. Such recirculation produces a diagnostic current pulse to a diode array for measuring a voltage drop across a portion of the array. For example, after a controller charges an inductor of a diode driver to deliver operating current pulses to a portion of a diode array for illumination, the controller causes a residual current to remain and recirculate in the inductor. In some implementations, in response to the recirculating current reaching a monitoring threshold, the controller delivers a monitoring pulse to the portion of the diode array to measure a voltage drop across the portion of the diode array. In some implementations, the controller may infer defectivity in the portion of the array from such voltage drop measurements over time.

A method for operating an optoelectronic system, in particular an LED system with at least one LED unit, is provided, comprising: Receiving voltage values ​​of an LED voltage drop across the at least one LED unit; Determining a voltage change of the LED voltage dropped across the at least one LED unit based on the voltage values ​​of the LED voltage; Determining a time interval during which the voltage change of the LED voltage dropping across the at least one LED unit occurs between a first predefined limit value and a second predefined limit value; Executing an operational function of the optoelectronic system based on the determined time interval. Furthermore, an optoelectronic system is provided.

The invention relates to an evaluation system. A method includes evaluating a first parameter, a second parameter, and a third parameter of a power switch. The first evaluation mode includes receiving a first sense current from the power switch at the common sense terminal; and measuring a first parameter during a switching event of the power switch based on the first sensed current. The second evaluation mode includes outputting a second sense current from the common sense terminal to the power switch; and measuring a second parameter dependent on a current flow of the second sense current through the power switch, the current flow dependent on an electrode voltage present at the drain or collector of the power switch. The third evaluation mode includes generating a third sense current at the common sense terminal; and measuring a third parameter generated based on the third sensed current and a temperature of the power switch.

The invention discloses an LED dead pixel detection method, device and equipment based on laser reflection and a medium, and relates to the technical field of LED lamp detection, and the method comprises the steps: controlling a laser light source to irradiate a to-be-detected LED lamp; collecting a reflected light signal; preprocessing the reflected light signal to obtain an input signal; and judging whether the LED lamp is normal based on the input signal. According to the invention, laser reflection detection is adopted to replace traditional optical imaging, the monochromaticity and directivity of laser are utilized to overcome ambient light interference, and a darkroom or complex filtering is not needed. Meanwhile, the combination of the laser light source and the photoelectric sensor significantly reduces the cost of the system, and avoids the use of a high-resolution camera. The laser can focus a micron-sized light spot, and the sub-pixel-level micro structure abnormity can be identified with high precision by analyzing the energy change of a reflected light signal. More importantly, according to the method, non-luminous defects such as packaging cracks and colloid stripping can be synchronously detected by capturing the reflection characteristics of the physical structure of the LED instead of depending on the luminous state of the LED, so that the defect detection accuracy is effectively improved.

A test method and apparatus for bipolar degradation of a diode, and a device. The method comprises: respectively performing static characteristic tests on a first diode and a second diode, so as to obtain a first static characteristic test result and a second static characteristic test result; setting a pulse test current, a pulse test time and a pulse cycle time, so that, on the basis of the pulse test current, the pulse test time and the pulse cycle time, a power semiconductor pulse current test device performs repeated short pulse current power cycle tests on the first diode under normal temperature conditions, and performs repeated short pulse current power cycle tests on the second diode under high temperature conditions; then, performing static tests, so as to obtain a plurality of static characteristic test results; and on the basis of the static characteristic test results, obtaining a bipolar degradation test result of a diode. By means of the method, bipolar degradation of the diode is tested, and the accuracy and reliability of the test result are improved.

A method for non-contact detection. The method includes providing a semiconductor device. The semiconductor device has an epitaxial stack, a first electrode and a second electrode connected to the epitaxial stack. The method further includes applying a microwave to the first electrode to cause the semiconductor device to emit light and detecting the light emitted from the semiconductor device.

Provided is a testing apparatus including: a light emission control unit which causes a plurality of light emitting elements to be tested to emit light; a light measurement unit which receives the light emitted from the plurality of light emitting elements and measures wavelengths of the received light; and a determination unit which determines whether there is an abnormality in at least one light emitting element on the basis of intensity distributions of the wavelengths of the light, which is emitted from the plurality of light emitting elements, measured by the light measurement unit. The testing apparatus may further include: a light source; an optical system which irradiates the plurality of light emitting elements with light emitted from the light source; and an electrical measurement unit which measures a photoelectric signal obtained by each of the plurality of light emitting elements photoelectrically converting the light radiated by the optical system.

The present application is to solve the problem that the optical characteristics of a plurality of LEDs cannot be inspected at the same time by a method of causing one of a pair of LEDs to emit light and causing the other to receive light, and using the current value of the current output by the photoelectric effect to inspect the optical characteristics of the LEDs. To solve the above problem, the present application proposes a test device provided with: an electrical connection portion electrically connected to the terminals of each of a plurality of LEDs that are test subjects; a light source portion that irradiates light to the plurality of LEDs at the same time; a measurement portion that measures a photoelectric signal that is photoelectrically converted by each of the plurality of LEDs with respect to the light irradiated by the light source portion and output via the electrical connection portion; and a determination portion that determines the good or bad of each of the plurality of LEDs based on the measurement result of the measurement portion.

Method for characterizing a batch of gain chips, each having a first reflective face and a second transparent face, the method comprising, for each gain chip: positioning the gain chip (99) with the second face facing towards a reflective diffraction grating (6); supplying the gain chip (99) with a plurality of first and second values of supply current so that the gain chip (99) emits a respective first light beam (60) for each first value of supply current and a respective second light beam (60') for each second value of supply current; making impinge each first light beam (60) on the reflective diffraction grating (6) in a first angular position so as to generate a respective first zero-order diffracted beam (61) and a respective first first-order diffracted beam (62) entering the gain chip (99), and each second light beam (60') on the reflective diffraction grating (6) in a second angular position so as to generate a respective second zero-order diffracted beam (63) and a respective second first-order diffracted beam (64) not entering the gain chip (99); measuring a respective first value of optical power of each first zero-order diffracted beam (61), and a respective second value of optical power of each second zero-order diffracted beam (63); associating each first value of optical power with the respective first value of supply current, and each second value of optical power with the respective second value of supply current; as a function of pairs of first values of supply current and of optical power and as a function of a first predetermined mathematical correlation, calculating a respective differential quantum efficiency, and, as a function of pairs of second values of supply current and of optical power and as a function of a second predetermined mathematical correlation, calculating a respective modal gain coefficient and a respective carrier density at transparency; verifying that the respective differential quantum efficiency, the respective modal gain coefficient, and the respective carrier density at transparency satisfy a respective predetermined selection criterion.

An inspection system includes an excitation light source, a voltage-sensing film, an illumination light source, an image capture device. The excitation light source provides an excitation beam to light-emitting diodes to generate open-circuit voltages. The voltage-sensing film is at a top side of the light-emitting diodes and includes a voltage-sensing medium layer and a first electrode layer. The first electrode layer is in the voltage-sensing medium layer to provide a gain effect of the open-circuit voltages, so that the voltage-sensing medium layer senses the open-circuit voltages, and a display of the voltage-sensing medium layer is changed with a portion or all of the open-circuit voltages. The illumination light source provides an illumination beam to the voltage-sensing film to generate a sensing image according to a display change. The image capture device is on a transmission path of the sensing image and receives the sensing image to generate an inspection result.

In a method of manufacturing a display device, the method includes providing a carrier module including a carrier wafer and light-emitting elements, forming a planarization layer between the light-emitting elements, forming a transparent electrode layer on the planarization layer, inspecting the light-emitting elements, and removing the planarization layer and the transparent electrode layer.

This disclosure relates to probe cards and methods for inspecting light-emitting diodes (LEDs) using the same. According to one aspect of this disclosure, the probe card includes: a probe substrate; a photodetector unit disposed on one surface of the probe substrate; and an electrode unit disposed on the photodetector unit and including a first sheath electrode and a second sheath electrode, the second sheath electrode including a through-hole overlapping the photodetector unit. Thus, the through-hole is formed in the second sheath electrode to allow light from the LED to be incident on the photodetector unit, and the electrode unit and the photodetector unit can simultaneously inspect the LED.

The invention provides a cartridge comprising a socket of insulative material and having upper and lower sides and a formation on the upper side to hold an electronic device; a set of contacts held in the socket to connect to the electronic device; a set of terminals connected to the set of contacts held by the socket; a circuit board, the set of terminals connected to the set of contacts being connected to a set of contacts on the circuit board; a lid; a detector mounted to the lid, the lid being movable to be positioned over the socket with the detector located in a position to detect a feature of the electronic device when and due to power being supplied through at least one of the set of terminals held by the socket to the electronic device; and a measurement channel connecting the detector to an interface on the circuit board.

The invention relates to a layout structure of a fast recovery diode and a test method, the layout structure of the fast recovery diode comprises a wafer which comprises odd-numbered line areas and even-numbered line areas which are alternately distributed, each odd-numbered line area comprises a plurality of first areas which are sequentially arranged along the line direction, and each even-numbered line area comprises a plurality of second areas which are sequentially arranged along the line direction; each even-numbered line area comprises a plurality of second areas which are sequentially arranged in the line direction; the first recovery diode and the second recovery diode are located in the second area, the second recovery diode is located on one side of the first recovery diode in the row direction, the first recovery diode has a first current specification, and the second recovery diode has a second current specification; and a third recovery diode in the first region, the third recovery diode having a third current specification, the size of the third current specification being greater than the size of the first current specification and greater than the size of the second current specification. According to the layout structure, test programs can be reduced, the test times can be reduced, the probe card cost can be reduced, and the productivity can be improved.

A device for measuring oxygen saturation is disclosed. The device includes circuitry configured to measure a first forward voltage across an anode and a cathode of a first light-emitting diode (LED) when a first current is applied, and to measure a second forward voltage across an anode and a cathode of a second light-emitting diode (LED) when a second current is applied. The circuitry is further configured to determine a difference in the measured forward voltages based on a comparison of the first and second forward voltages, and to determine that the first and second LEDs are valid based on a difference in the calibrated forward voltages and the measured forward voltages. In response to determining that the first and second LEDs are valid, the circuitry is configured to determine an oxygen saturation level.

This invention provides an electronic device comprising a substrate, an electronic unit, a data line, a control unit, a test pad, and a test switch element. The substrate includes a first surface and a second surface opposite to the first surface, wherein the first surface includes an active region. The electronic unit is disposed on the substrate and located within the active region. The data line is disposed on the substrate. The control unit is disposed on the substrate and located within the active region, and the control unit is electrically connected between the electronic unit and the data line. The test pad is disposed on the second surface of the substrate. The test switch element is disposed on the substrate and located within the active region, and the test switch element is electrically connected between the data line and the test pad.

The invention provides a cartridge comprising a socket made of insulative material and having upper and lower sides, the upper side having a first formation for releasably holding a first electronic device, the socket having a first socket thermal opening formed from the lower side to the upper side through the socket, an interface connected to the socket to connect the first electronic device to an electric tester, a chuck of a thermally conductive material, a first thermal post attached to the chuck, the first thermal post being inserted into the first socket thermal opening, an end of the first thermal post being thermally connected to and in contact with the first electronic device, such that heat transfers primarily through the first thermal post as opposed to the insulative material of the socket between the chuck and the first electronic device, and a first set of contacts held in the socket and connecting terminals of the first electronic device to the interface, the first set of contacts being resiliently depressible to bring the first electronic device into contact with the end forming a first thermal surface of the first thermal post.

The invention provides a cartridge comprising an electronic device holder having a formation for removably holding an electronic device having an input contact and a light emitter; an input contact on the electronic device holder to connect to the input contact on the electronic device to provide an input electric power through the input contact on the electronic device holder to the input contact on the electronic device, the input electric power causing the light emitter to transmit light; a light detector mounted to the electronic device holder and positioned to detect the light and generate an output electric power in response to a magnitude of the light; and an output contact connected to the light detector to measure the output electric power.

The application discloses a method for testing response time of a mini / micro LED direct display screen, which can avoid the influence of subjective evaluation of human visual perception on the response time, and provides a means for high-precision testing of the response time of the direct display screen through quantitative evaluation method. The method comprises the following steps: (1) a power supply inputs a stable voltage to the direct display screen, the direct display screen is lighted when a square wave driving voltage is input, light enters a microscope lens and converges on a target surface of a high-speed photoelectric detector, a response voltage signal is generated after the target surface is irradiated by the light, the voltage signal is filtered by a high-frequency filter to suppress high-frequency noise, and the voltage signal is connected to an oscilloscope through a BNC line; (2) the power supply is driven and controlled to realize different refresh rates; and step (1) is repeated to realize the response time test of the direct display screen under different refresh rates; and (3) different colors are realized by controlling a signal of the driving power supply; and step (1) is repeated to realize the response time test of the direct display screen under different colors.

A plurality of electrodes (13) are provided on tip ends of a plurality of blocks (8) respectively. The plurality of lead terminals (3) are sandwiched by the plurality of blocks (8) and the plurality of wires (9) to correct positions of the plurality of lead terminals (3). The plurality of electrodes (13) are brought into contact with the plurality of lead terminals (3) to inspect an electrical characteristic of the optical semiconductor device (1).

The invention discloses a power module junction temperature estimation method, which comprises the following steps of: calculating the total loss of a power component based on input three-phase current, three-phase duty ratio, bus voltage, sector position and carrier frequency; according to the obtained total loss and the DBC temperature collected in real time, the cooling water flow is estimated through a temperature difference method; based on the obtained total loss, the cooling water flow and the real-time DBC temperature, the cooling water estimated temperature of the corresponding phase is calculated; calculating the junction temperature by using the obtained total loss, the thermal resistance value corresponding to the cooling water flow and the obtained estimated temperature of the cooling water; and after the obtained three-phase junction temperature is maximized, a compensation table is selected according to the working condition of the motor to carry out compensation correction, and the high-precision estimated junction temperature is output. According to the method, cooling parameters are dynamically obtained through a collaborative estimation process, compensation is carried out according to working conditions, and high-precision junction temperature estimation without a direct temperature sensor is achieved.

The invention discloses a failure detection circuit and method for an absorption diode in an IGCT power module, the circuit comprises a detection module and a control module which are connected in sequence, the detection module is electrically connected with a to-be-detected IGCT power module and is used for detecting current in a suppression reactor in the IGCT power module, the detection module is used for transmitting a detection signal to the control module, and the control module is used for controlling the absorption diode in the IGCT power module. And the control module is used for judging whether the absorption diode fails or not according to a detection signal of the detection module, outputting a control signal to the IGCT power module and controlling the working state of each IGCT device. The detection module detects the bus voltage of the converter, the pulse starting signal of the IGCT power module and the current signal on the suppression reactor, and judges whether the absorption diode fails or not according to the detection result of the current signal on the suppression reactor when the bus voltage is normal and the IGCT power module is started, so that the damage probability of the IGCT power module is reduced, and the service life of the IGCT power module is prolonged. And the operation reliability of the IGCT power module is enhanced.