CN109060164B - Light-emitting device temperature distribution measuring device and method based on microscopic hyperspectrum - Google Patents
Light-emitting device temperature distribution measuring device and method based on microscopic hyperspectrum Download PDFInfo
- Publication number
- CN109060164B CN109060164B CN201811113037.XA CN201811113037A CN109060164B CN 109060164 B CN109060164 B CN 109060164B CN 201811113037 A CN201811113037 A CN 201811113037A CN 109060164 B CN109060164 B CN 109060164B
- Authority
- CN
- China
- Prior art keywords
- temperature
- sample
- power supply
- hyperspectral
- temperature control
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K11/00—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Led Devices (AREA)
- Spectrometry And Color Measurement (AREA)
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
Abstract
a device and a method for measuring the temperature distribution of a luminescent device based on microscopic hyperspectrum belong to the field of testing the temperature distribution of the luminescent device and comprise a temperature control table, a driving power supply, a temperature control power supply, a microscope, a hyperspectral meter and a computer; setting the initial temperature of the sample, and selecting a pulse signal to drive the sample by using a driving power supply; adjusting a temperature control power supply, changing the temperature of a temperature control table, and acquiring hyperspectral data of the sample at a corresponding temperature point by a hyperspectral meter; the computer calculates a two-dimensional temperature sensitivity coefficient matrix according to the hyperspectral data; adjusting a driving power supply to a constant voltage or constant current mode, and collecting hyperspectral data of the sample by using a hyperspectral meter; calculating the centroid wavelength by using hyperspectral data in a constant-voltage or constant-current mode by using a computer, and obtaining the two-dimensional temperature distribution of the surface of the sample by combining a two-dimensional temperature sensitivity coefficient matrix; the spectral image of each pixel point on the surface of the light-emitting device can be obtained, so that the two-dimensional temperature distribution map of the surface of the light-emitting device can be accurately obtained, and the surface temperature change trend of the light-emitting device can be visually embodied.
Description
Technical Field
The invention belongs to the field of testing the temperature distribution of a luminescent device, and particularly relates to a device and a method for measuring the temperature distribution of the luminescent device based on microscopic hyperspectrum.
Background
in the energy economy age of the 21 st century, light emitting devices such as semiconductor Light Emitting Diodes (LEDs) have been widely used in various fields such as daily life, electronic technology, military, and the like, because of their advantages of small size, long life, and fast response speed. The LED converts electric energy into light energy, but 60% -70% of the electric energy can be converted into heat energy, and if a large amount of heat is not dissipated, junction temperature is too high, and the service life of the LED is seriously influenced. Therefore, the research on the junction temperature of the LED has profound significance.
at present, a method for measuring junction temperature of a light emitting device is to perform indirect test by using a relation between a certain characteristic of the device and temperature, and mainly includes a forward voltage drop method, a spectrum blue-white ratio method, a spectrum peak wavelength method, a spectrum centroid wavelength and full width at half maximum, infrared thermal imaging and the like.
The forward voltage drop method is a commonly used method for measuring junction temperature at present, and is a method for performing junction temperature test by using the relationship that the voltage at two ends of a device and the temperature are linearly changed, but the test precision is limited by the switching speed from heating a large current to testing a small current, and for a packaged lamp finished product, due to the limitations of lamp shell materials and the like, it is generally difficult to accurately measure the voltage drop on each LED pin ([1] Ryu H Y, Ha K H, Chae J H, et al.measurement of junction temperature in GaN-based laser diodes using voltage-temperature characteristics [ J ]. Applied Physics Letters,2005,87(9): 297.).
the main principle of the spectrum blue-white ratio method is that with the increase of junction temperature, the luminescence of the chip and the photoluminescence of the fluorescent powder are simultaneously reduced, but the luminescence of the fluorescent powder is reduced more rapidly, so that the proportion of blue-white light in a white light spectrum is changed. The disadvantage of this method is that it is not suitable for the measurement of junction temperature of monochromatic LEDs ([2] Tetsushi Tamura, Tatsumi Setomo, Tsunema Taguchi. illumination characteristics of lighting array using 10 candela-glass white LEDs under AC 100V operation [ J ]. Journal of Luminescence center, 2000, 87.).
The spectral peak wavelength method is to measure the junction temperature of the LED through the drift relation of the peak wavelength with the junction temperature. The disadvantages of this method are that the spectral peak wavelength changes little, resulting in large actual measurement errors, large influence by the laboratory instruments, and inconsistent law of variation of different LED peak wavelengths with temperature ([3] y.xi, j.q.xi, t.gessmann, j.m.shah, j.k.kim, e.f.schubert, a.j.fischer, m.h.crawford, k.h.a.bogart, and a.a.allerman, "junton and carrier temporal measurements in deep-ultraviolet light-emitting diodes using same method," application.phys.let., vol.86, No.3, 031.907, jan.2005).
the spectrum centroid wavelength and full width at half maximum method is based on the mathematical model relation of optical parameters (centroid wavelength and full width at half maximum) and junction temperature and direct current drive current. The method is characterized in that the direct current driving current is increased and the heat sink temperature is reduced, so that the function relation among optical parameters, current and junction temperature is corrected under the condition that the overall junction temperature is constant, and the expression of the junction temperature (4 Y.Lin, Y.L.Gao, Y.J.Lu, L.H.Zhu, Y.Zhang and Z.Chen, Study of temporal sensitive optical parameters and junction temporal determination of light-emitting diodes, Appl.Phys.Lett, vol.100, pp.202108, May.2012) is obtained.
the methods are all directed to testing the average temperature of the light-emitting device, and only one average temperature can be obtained to represent the temperature of the light-emitting device. However, the surface temperature of the light emitting device is distributed in two dimensions, and the temperature distribution at each position is not completely consistent. Infrared thermography measures the two-dimensional Temperature distribution of an object surface by its infrared radiation, and has the disadvantage of being easily affected by the device package structure, and of being difficult to detect the surface of the packaged LED chip ([5] Tamdogan E, Pavlidis G, Graham S, et al.A. Comparative Study on the Junction Temperature Measurements of LEDs, micro-front (IR) Imaging, and Forward Voltage Methods [ J ]. IEEE Transactions on composites Packaging & Manufacturing Technology,2018, PP (99): 1-9.).
The hyperspectral technology is a new comprehensive detection technology in recent years, image information and spectral data are organically combined into a three-dimensional data cube integrating a map, and multiple field technologies such as an imaging technology, an electronic technology, an information technology and a computer technology are fused.
Disclosure of Invention
the invention aims to solve the problems in the prior art, and provides a device and a method for measuring the temperature distribution of a light-emitting device based on microscopic hyperspectrum, which can accurately obtain the spectral image of each pixel point on the surface of the light-emitting device, thereby accurately obtaining the two-dimensional temperature distribution map of the surface of the light-emitting device and visually embodying the surface temperature change trend of the light-emitting device.
in order to achieve the purpose, the invention adopts the following technical scheme:
The device for measuring the temperature distribution of the light-emitting device based on the microscopic hyperspectrum comprises a temperature control table, a driving power supply, a temperature control power supply, a microscope, a hyperspectral meter and a computer, wherein the temperature control table is used for fixing a sample;
The driving power supply is connected with the sample and is used for driving the sample;
the temperature control power supply is connected with the temperature control table and is used for controlling the temperature of the sample;
The microscope is arranged above the sample and is used for transmitting light emitted by the sample;
the hyperspectral meter is arranged above the microscope and used for collecting light transmitted by the microscope and obtaining hyperspectral data;
and the computer is connected with the hyperspectral spectrometer and is used for calculating the received hyperspectral data to obtain the two-dimensional temperature distribution of the surface of the sample.
The driving power supply comprises a pulse voltage mode, a pulse current mode, a constant voltage mode and a constant current mode.
A light-emitting device temperature distribution measuring method based on microscopic hyperspectrum comprises the following steps:
Step 1, fixing a sample on a temperature control table, setting the initial temperature T0 of the sample, and controlling the temperature of the sample to be T0 by using a temperature control power supply;
Step 2, adjusting a driving power supply to a pulse voltage or pulse current mode, and selecting a short pulse signal to drive a sample;
step 3, adjusting a temperature control power supply, sequentially changing the temperature of a temperature control table to be T0, T1 and T2 … …, enabling light emitted by a sample to enter a hyperspectral meter through a microscope, and acquiring hyperspectral data of the sample at a corresponding temperature point by the hyperspectral meter;
step 4, fitting the sensitivity coefficient relation between the centroid wavelength and the surface temperature of the sample by the computer according to the hyperspectral data to obtain a two-dimensional temperature sensitivity coefficient matrix;
Step 5, adjusting the driving power supply to a constant voltage mode or a constant current mode, wherein the voltage or current corresponds to high level voltage or current under the pulse, light emitted by the sample enters the hyperspectral meter through the microscope, and the hyperspectral meter is used for collecting spectral data of the sample under the constant voltage or constant current mode;
and 6, calculating the centroid wavelength by using hyperspectral data in a constant voltage mode or a constant current mode by using a computer, and obtaining the two-dimensional temperature distribution of the surface of the sample by combining the two-dimensional temperature sensitivity coefficient matrix obtained in the step 4.
compared with the prior art, the technical scheme of the invention has the following beneficial effects:
1. the invention utilizes the principle of linear relation that the spectral centroid wavelength of each pixel point of the luminescent device changes with the temperature to test the two-dimensional temperature distribution of the luminescent device, compared with other junction temperature test methods, the microscopic hyperspectral technology has high spatial resolution and spectral resolution, and can accurately obtain the spectral image of each pixel point on the surface of the luminescent device, thereby accurately obtaining the two-dimensional temperature distribution map of the surface of the luminescent device and visually embodying the surface temperature change trend.
2. The invention has wide application range and is not influenced by the packaging of the light-emitting device, and the two-dimensional temperature distribution on the surface of the light-emitting chip can be obtained by packaging only through light emission no matter whether the light-emitting device is packaged or not or whether other materials are covered.
Drawings
FIG. 1 is a schematic flow chart of the present invention;
FIG. 2 is a graph of linear fitting relationship between centroid wavelength and temperature of a blue LED;
FIG. 3 is a two-dimensional temperature distribution graph of a surface of a blue LED calculated in a constant voltage mode at 25 ℃;
FIG. 4 is a longitudinal temperature variation trend graph of the position A of the blue LED in FIG. 3;
FIG. 5 is a lateral temperature variation trend graph of the B position of the blue LED in FIG. 3;
Fig. 6 is a statistical graph of the calculated surface two-dimensional temperature points of the blue LED in the constant voltage mode at 25 ℃.
reference numerals: 1-driving power supply, 2-temperature control power supply, 3-temperature control table, 4-sample, 5-microscope, 6-hyperspectral meter and 7-computer.
Detailed Description
in order to make the technical problems, technical solutions and advantageous effects of the present invention clearer and clearer, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.
As shown in fig. 1, the invention comprises a driving power supply 1, a temperature control power supply 2, a temperature control table 3, a microscope 5, a high-speed spectrometer 6 and a computer 7; wherein:
the temperature control table 3 is used for fixing a sample 4;
the driving power supply 1 is connected with the sample 4, and the driving power supply 1 is used for driving the sample 4; the driving power supply 1 comprises a pulse voltage mode, a pulse current mode, a constant voltage mode and a constant current mode;
the temperature control power supply 2 is connected with the temperature control table 3, and the temperature control power supply 2 is used for controlling the temperature of the sample 4;
The microscope 5 is arranged above the sample 4, and the microscope 5 is used for transmitting light emitted by the sample 4;
The hyperspectral meter 6 is arranged above the microscope 5, and the hyperspectral meter 6 is used for collecting light transmitted by the microscope 5 and obtaining hyperspectral data;
The computer 7 is connected with the hyperspectral meter 6, and the computer 7 is used for calculating the received hyperspectral data to obtain the two-dimensional temperature distribution of the surface of the sample 4.
The sample in the present invention is a light emitting device.
The invention combines the hyper-spectral technology and the microscopic technology to obtain the spectral information of each pixel point of the surface of the luminescent device with high resolution, and utilizes the linear relation of the centroid wavelength along with the temperature change to correct the temperature by using a voltage or current pulse signal.
The centroid wavelength is the geometrically symmetric wavelength of the spectral distribution, defined as follows:
Wherein: f (λ) is the spectral distribution of the light emitting device; λ is the wavelength, λ 1, λ 2 are the upper and lower limit wavelengths of the spectral distribution, and the visible light range is usually 380-780 nm.
The centroid wavelength-temperature sensitivity coefficient Kij of any pixel point is as follows:
wherein: t0, T is the initial temperature of the temperature control table and another control temperature respectively; i is 1 … x, j is 1 … y, x and y are hyperspectral imaging dimensional pixels, and Δ λ cxy is the difference of the centroid wavelength of the xy pixel point under the temperature T and the temperature T0.
the two-dimensional temperature sensitivity coefficient matrix of all the pixel points on the surface is as follows:
the difference matrix of the centroid wavelengths of all the pixel points on the surface of the device at the temperature to be measured and the initial temperature is as follows:
then, the two-dimensional temperature distribution matrix of all the pixel points on the surface of the light emitting device is:
in this embodiment, the method for measuring a sample to be measured by using a blue LED specifically includes the following steps:
Step 1, fixing the blue light LED on a temperature control table 3, controlling the heat sink temperature of a sample 4 to be 25 ℃ by using a temperature control power supply 2, and not electrifying the blue light LED.
step 2, adjusting the driving power supply 1 to make the signal thereof be: and the blue LED is electrified under a short pulse voltage mode with the pulse period of 2ms, the high level of 3V, the low level of 0V and the duty ratio of 3 percent (generally, the pulse width is controlled to be less than 1ms, and the influence of self-heating effect can be better avoided).
and 3, adjusting the temperature control power supply 2, sequentially controlling the heat sink temperature of the sample 4 to be 25 ℃, 35 ℃, 45 ℃, 55 ℃, 65 ℃ and 75 ℃, enabling light emitted by the sample 4 to enter the hyperspectral meter 6 through the microscope 5, and enabling the hyperspectral meter 6 to collect hyperspectral data of the blue LED to the computer 7.
and 4, calculating the centroid wavelength of each pixel point on the surface of the chip by the computer 7 from the hyperspectral data, fitting a centroid wavelength-temperature sensitivity relation of each pixel point according to the formula (1), and obtaining a two-dimensional temperature sensitivity coefficient matrix K of all pixel points shown in the formula (2) by a centroid wavelength and temperature linear fitting relation curve chart of the blue light LED shown in figure 2.
and 5, adjusting the driving power supply 1 again, and electrifying the blue LED in a constant voltage mode corresponding to the pulse high level of 3V.
and 6, repeating the step 3 to obtain hyperspectral data of the blue LED under the constant voltage of 3V at the heat sink temperatures of 25 ℃, 35 ℃, 45 ℃, 55 ℃, 65 ℃ and 75 ℃ respectively.
and 7, extracting the centroid wavelength from the obtained hyperspectral data in the constant voltage mode, and obtaining a two-dimensional temperature distribution diagram of the surface of the blue LED under constant voltage and different heat sink temperatures according to the two-dimensional temperature sensitivity coefficient matrix K obtained in the step 4 and formulas (3) and (4), wherein the surface two-dimensional temperature distribution diagram is calculated by the blue LED under the constant voltage mode of 25 ℃ as shown in fig. 3. Fig. 4 and 5 are graphs of longitudinal and transverse temperature variation trends of the blue light LED. Since there are many two-dimensional surface temperature points, in order to compare with the thermocouple result, to verify the reliability of the present invention, the median temperature of the subgroup with the highest occurrence frequency, i.e., the mode temperature, in the group with the temperature interval of 0.1 ℃ is taken, and the mode temperature is the representative surface temperature under the condition, as shown in fig. 6, a statistical graph of the surface two-dimensional temperature points calculated by the blue LED under the constant voltage mode of 25 ℃.
And 8, measuring the surface temperature of the blue LED at the constant voltage of 3V and at the heat sink temperatures of 25 ℃, 35 ℃, 45 ℃, 55 ℃, 65 ℃ and 75 ℃ by using a thermocouple, comparing the surface temperature with the mode temperature calculated in the step 7, and confirming the reliability of the method, wherein the average error is less than 0.7 ℃.
TABLE 1 (. degree. C.)
| temperature of heat sink | 25 | 35 | 45 | 55 | 65 | 75 | Mean error |
| Temperature measured by the method | 34.0 | 46.6 | 56.8 | 66.6 | 77.0 | 88.1 | / |
| Thermocouple measuring temperature | 35.1 | 45.6 | 54.9 | 66.1 | 75.3 | 88.0 | / |
| Single random error | -1.1 | 1.0 | 1.9 | 0.5 | 1.7 | 0.1 | 0.7 |
example blue LEDs are shown in table 1, which shows representative surface temperatures (mode temperatures) obtained by microscopic hyperspectral techniques at different temperatures compared to the surface temperature measured by a thermocouple.
Claims (1)
1. A light-emitting device temperature distribution measuring method based on microscopic hyperspectrum is characterized in that: the measuring device adopted by the measuring method comprises a temperature control table, a driving power supply, a temperature control power supply, a microscope, a hyperspectral meter and a computer;
The temperature control table is used for fixing a sample;
The driving power supply is connected with the sample and is used for driving the sample; the driving power supply comprises a pulse voltage mode, a pulse current mode, a constant voltage mode and a constant current mode;
the temperature control power supply is connected with the temperature control table and is used for controlling the temperature of the sample;
The microscope is arranged above the sample and is used for transmitting light emitted by the sample;
The hyperspectral meter is arranged above the microscope and used for collecting light transmitted by the microscope and obtaining hyperspectral data;
the computer is connected with the hyperspectral spectrometer and used for calculating the received hyperspectral data to obtain two-dimensional temperature distribution of the surface of the sample;
the measuring method comprises the following steps:
Step 1, fixing a sample on a temperature control table, setting the initial temperature T0 of the sample, and controlling the temperature of the sample to be T0 by using a temperature control power supply;
step 2, adjusting a driving power supply to a pulse voltage or pulse current mode, and selecting a short pulse signal to drive a sample;
step 3, adjusting a temperature control power supply, sequentially changing the temperature of a temperature control table to be T0, T1 and T2 … …, enabling light emitted by a sample to enter a hyperspectral meter through a microscope, and acquiring hyperspectral data of the sample at a corresponding temperature point by the hyperspectral meter;
Step 4, fitting the sensitivity coefficient relation between the centroid wavelength and the surface temperature of the sample by the computer according to the hyperspectral data to obtain a two-dimensional temperature sensitivity coefficient matrix;
step 5, adjusting the driving power supply to a constant voltage mode or a constant current mode, wherein the voltage or current corresponds to high level voltage or current under the pulse, light emitted by the sample enters the hyperspectral meter through the microscope, and the hyperspectral meter is used for collecting spectral data of the sample under the constant voltage or constant current mode;
and 6, calculating the centroid wavelength by using hyperspectral data in a constant voltage mode or a constant current mode by using a computer, and obtaining the two-dimensional temperature distribution of the surface of the sample by combining the two-dimensional temperature sensitivity coefficient matrix obtained in the step 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811113037.XA CN109060164B (en) | 2018-09-25 | 2018-09-25 | Light-emitting device temperature distribution measuring device and method based on microscopic hyperspectrum |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811113037.XA CN109060164B (en) | 2018-09-25 | 2018-09-25 | Light-emitting device temperature distribution measuring device and method based on microscopic hyperspectrum |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109060164A CN109060164A (en) | 2018-12-21 |
| CN109060164B true CN109060164B (en) | 2019-12-06 |
Family
ID=64762478
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811113037.XA Active CN109060164B (en) | 2018-09-25 | 2018-09-25 | Light-emitting device temperature distribution measuring device and method based on microscopic hyperspectrum |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109060164B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110658169B (en) * | 2019-10-14 | 2021-05-14 | 厦门大学 | Hyperspectrum-based transmission-type testing device and method for luminescent characteristics of fluorescent powder |
| CN113639891A (en) * | 2020-09-03 | 2021-11-12 | 深圳阿珂法先进科技有限公司 | High-speed optical fiber temperature sensing demodulation method based on equivalent wavelength |
| CN113588091A (en) * | 2021-07-26 | 2021-11-02 | 沈阳理工大学 | System and method for measuring temperature of metal molten pool in laser selected area in real time by utilizing hyperspectrum |
| CN113551797A (en) * | 2021-07-28 | 2021-10-26 | 厦门大学 | Method for testing two-dimensional temperature distribution of LED fluorescent powder surface |
| CN114047224B (en) * | 2021-11-24 | 2023-04-07 | 江苏省特种设备安全监督检验研究院 | Method for testing junction temperature and temperature distribution of gallium nitride-based blue light LED |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103376169A (en) * | 2012-04-28 | 2013-10-30 | 杭州鸿雁电器有限公司 | Method for measuring temperature of LED chip and encapsulated active region with high precision and high spatial resolution |
| CN102680878B (en) * | 2012-05-29 | 2015-04-22 | 陕西科技大学 | Experiment method of junction temperature of LED (light emitting diode) |
| CN102829890B (en) * | 2012-08-07 | 2015-01-28 | 陕西科技大学 | Device and method for measuring junction temperature of LED (light emitting diode) |
| CN203178831U (en) * | 2013-02-06 | 2013-09-04 | 南京千韵电子科技有限公司 | Chip internal temperature control device and experimental instrument |
| CN104729742A (en) * | 2013-12-21 | 2015-06-24 | 中科科隆光电仪器设备无锡有限公司 | Non-contact LED whole-lamp junction temperature measuring system |
| CN104019908A (en) * | 2014-06-16 | 2014-09-03 | 常州工学院 | LED junction temperature or average LED array junction temperature measuring method |
| CN105300550B (en) * | 2015-10-09 | 2018-06-01 | 中国工程物理研究院流体物理研究所 | A kind of measuring method and system of the distribution of device micro-meter scale two-dimension temperature |
| CN106679818B (en) * | 2016-12-31 | 2023-10-24 | 宁波大学 | Device and method for measuring temperature distribution of smooth surface |
-
2018
- 2018-09-25 CN CN201811113037.XA patent/CN109060164B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN109060164A (en) | 2018-12-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109060164B (en) | Light-emitting device temperature distribution measuring device and method based on microscopic hyperspectrum | |
| CN103234656B (en) | Measuring method for junction temperature of LED (light emitting diode) | |
| CN110057466B (en) | Surface temperature measuring method based on LED fluorescence emission spectrum | |
| CN103592590B (en) | The test macro that a kind of LED component photoelectric heat is integrated and method | |
| CN115291071B (en) | LED array photo-thermal integrated detection device and method based on lock-in amplifier | |
| CN103175624A (en) | Non-contact LED junction temperature measurement method and device | |
| TWI626431B (en) | Method and system for characterizing light emitting devices | |
| Jin et al. | A microscopic hyperspectral-based centroid wavelength method for measuring two-dimensional junction temperature distribution of LEDs | |
| CN105318985B (en) | A kind of device and method by reflected light relative intensity measure body surface temperature | |
| Chen et al. | A design for in-situ measurement of optical degradation of high power light-emitting diodes under accelerated life test | |
| CN105784185B (en) | A kind of devices and methods therefor of variation measuring and calculating LED junction temperature according to spatial distribution | |
| Zhu et al. | 2-D photo-thermal distribution and structures of flip-chip mini light-emitting diodes by microscopic hyperspectral imaging | |
| Abbing et al. | Light-emitting diode junction-temperature sensing using differential voltage/current measurements | |
| Lin et al. | Determining phosphor temperature in light-emitting diode based on divisional normalized emission power | |
| CN113551797A (en) | Method for testing two-dimensional temperature distribution of LED fluorescent powder surface | |
| CN104006898B (en) | Method for representing junction temperature of GaN-based LED through weighting width | |
| KR101266387B1 (en) | Device and method of measuring of light emitting diode | |
| CN111220295A (en) | Automatic detection equipment and measurement method for non-contact measurement of junction temperature of LED lamp | |
| Liu et al. | Determining 2-D Optical Characteristics-Dependent Surface Temperature of Organic Light-Emitting Diode | |
| TW201314185A (en) | System for light-emitting diode spectrum measurement | |
| Wang et al. | The analysis of measurement methods for high power LED thermal resistance | |
| Fu et al. | An engineering method to estimate the junction temperatures of light-emitting diodes in multiple LED application | |
| Bouchard et al. | Optical and electrical variations in high-power white light-emitting diodes stressed with typical operation conditions | |
| Cui et al. | Two characteristic parameters for the junction temperature of white LED | |
| Ju et al. | Losses of Energy in Phosphor of LED at Transformation of Emission Spectrum |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |