LED lamp bead variable temperature testing device

Abstract

The utility model discloses a LED lamp pearl variable temperature testing arrangement relates to the field of semiconductor photoelectric testing technology. The device aims at solving the problem that the existing testing equipment can not realize quick, accurate and uniform temperature control in wide temperature range. The device includes double -layer heat -insulating cavities by outer test storehouse and inner test storehouse constitute, its inside is equipped with the test board for fixing LED lamp pearl, the upper and lower surface of test board is attached respectively thermoelectricity refrigeration piece, and its hot face is connected independent radiator respectively, the periphery of test board is provided with heater, and the inside of test board, LED installation position and cavity environment are provided with temperature sensor respectively, and are equipped with three -way temperature controller, and the outer test storehouse wall is provided with electrical and optical test interface. The utility model can realize the wide temperature area of -20 DEG C to 150 DEG C, fast, high accuracy temperature control, and the structure is compact, is applicable to the variable temperature photoelectric characteristic test of LED semiconductor photoelectric device.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor optoelectronic testing, specifically to a device for testing the temperature-dependent characteristics of LED beads, which is particularly suitable for testing the IV characteristics, optical power and spectral response of ultraviolet LED beads in a wide temperature range (-20℃ to 150℃). Background Technology

[0002] As an emerging optoelectronic technology, ultraviolet (UV) LED light sources are widely used in medical, environmental protection, and disinfection fields. However, their optical and electrical properties vary significantly under different temperature conditions, especially in high-power-density applications where the temperature rise effect has a particularly significant impact on performance. Existing testing methods are mostly limited to near-room temperature (room temperature to around 80°C), lacking equipment and methods for systematically testing the IV curves, optical power, and spectral response of UV LED chips over a wide temperature range (-20°C to 150°C). In particular, there is a lack of a complete testing platform capable of systematically extracting the wavelength drift coefficient (Δλ / ΔT) and efficiency temperature coefficient (ΔEQE / ΔT). Therefore, developing a simple, highly accurate, and wide-temperature-range-suitable UV LED chip temperature-dependent testing device has become an urgent problem for the industry. Utility Model Content

[0003] In order to overcome the shortcomings of the existing technology, this utility model provides an LED lamp bead temperature change testing device with compact structure, wide temperature control range, fast response speed and good temperature uniformity.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: An LED bead temperature-changing testing device, characterized in that it comprises: a base; an outer test chamber mounted on the base and an inner test chamber disposed inside the outer test chamber, wherein a heat-insulating gap exists between the outer test chamber and the inner test chamber; a test platform disposed in the center of the inner test chamber for placing the LED bead to be tested; a heater disposed in the inner test chamber; a first thermoelectric cooler and a second thermoelectric cooler, the cold surfaces of which are respectively thermally connected to the upper and lower surfaces of the test platform, and the hot surfaces of which are respectively connected to independent heat sinks; a first temperature sensor disposed in the test platform for detecting the temperature of the test platform; a second temperature sensor disposed in the inner test chamber near the test platform for detecting the ambient temperature of the LED bead; a third temperature sensor disposed in the outer test chamber for detecting the temperature of the outer test chamber; a first temperature controller connected to the first temperature sensor and the heater, a second temperature controller connected to the second temperature sensor and the first thermoelectric cooler, and a third temperature controller connected to the third temperature sensor and the second thermoelectric cooler.

[0005] Preferably, it also includes an electrical test interface and an optical test interface. The electrical test interface is electrically connected to the test bench and is used to connect to external electrical test equipment. The optical test interface is located outside the outer test chamber, directly above the LED beads, and is used to connect to external optical test equipment. The outer test chamber and the inner test chamber are provided with light-transmitting openings between the optical test interface and the LED beads.

[0006] Preferably, the test platform is a copper test platform, which can be cylindrical.

[0007] Preferably, the surface of the test stage is provided with a layer of highly thermally conductive silicone grease.

[0008] Preferably, the heat sink is an aluminum heat sink fin assembly.

[0009] Preferably, the second temperature sensor is a thermocouple attached to the substrate of the LED bead under test, or an infrared temperature sensor fixed to the top wall of the inner test chamber with its lens aligned with the test stage.

[0010] Preferably, the heat insulation gap between the outer test chamber and the inner test chamber is 20mm to 30mm.

[0011] Preferably, the electrical test interface is a four-wire Kelvin BNC interface or an aviation plug.

[0012] Preferably, the optical testing interface is a flange-type fiber optic interface.

[0013] Preferably, it also includes an external fan and an internal fan. The external fan is disposed inside the external test chamber and is used to dissipate heat from the heat sink of the first thermoelectric cooling chip and / or the second thermoelectric cooling chip. The internal fan is disposed inside the internal test chamber and is used to promote air circulation inside the internal test chamber.

[0014] Furthermore, the spacing of the air insulation layer is 20mm to 30mm.

[0015] This invention achieves wide-range, rapid, and high-precision temperature control from -20℃ to 150℃ through double-layer insulation, double-sided thermoelectric cooling on the test bench with independent heat dissipation, and a three-level independent temperature control system. It solves the problems of narrow temperature range, slow temperature control, and poor uniformity of existing equipment, and provides an effective tool for the study of the thermoelectric characteristics of LED devices. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a device for testing the temperature characteristics of LED beads.

[0017] In the diagram: 1-Base; 2-Outer test chamber; 3-Inner test chamber; 4-Test platform; 5-Heater; 6-First thermoelectric cooler; 7-Second thermoelectric cooler; 8-First temperature controller; 9-Second temperature controller; 10-Third temperature controller; 11-Electrical test interface; 12-Optical test interface; 13-Inner fan; 14-Outer fan; 15-First temperature sensor; 16-Second temperature sensor; 17-Third temperature sensor. Detailed Implementation

[0018] The embodiments of this utility model will be further described in detail below with reference to the accompanying drawings, but are not limited to the following embodiments. All technical solutions within the scope of the concept of this invention should be included within the protection scope of this utility model.

[0019] Example 1: like Figure 1As shown, the LED bead temperature testing device of this embodiment includes: a base 1; an outer test chamber 2 mounted on the base and an inner test chamber 3 disposed inside the outer test chamber, with a heat insulation gap between the outer and inner test chambers; a test platform 4 disposed in the center of the inner test chamber for placing the LED bead to be tested; a heater 5 disposed in the inner test chamber; a first thermoelectric cooling element 6 and a second thermoelectric cooling element 7, the cold surfaces of which are thermally connected to the upper and lower surfaces of the test platform, respectively, and the hot surfaces of which are respectively connected to independent heat sinks; a first temperature sensor 15 disposed in the test platform; a second temperature sensor 16 disposed in the inner test chamber, near the test platform; and a third temperature sensor 15 disposed in the inner test chamber. Sensor 17 is disposed in the air of the outer test chamber 2; a first temperature controller 8 is signal-connected to the first temperature sensor 15 and the heater 5, a second temperature controller 9 is signal-connected to the second temperature sensor 16 and the first thermoelectric cooler 6, and a third temperature controller 10 is signal-connected to the third temperature sensor 17 and the second thermoelectric cooler 7; it also includes an electrical test interface 11 and an optical test interface 12. The electrical test interface 11 is electrically connected to the test platform 4 for connecting external electrical test equipment, and the optical test interface is located outside the outer test chamber, directly above the LED beads, for connecting external optical test equipment. The outer and inner test chambers have a light-transmitting opening between the optical test interface and the LED beads. The light-transmitting opening can be a light-transmitting hole or made of a transparent material such as glass; it also includes an external fan 14 and an internal fan 13. The external fan 14 is disposed inside the outer test chamber for heat dissipation of the heat sink of the first thermoelectric cooler and / or the second thermoelectric cooler; the internal fan 13 is disposed inside the inner test chamber for promoting air circulation within the inner test chamber. The outer test chamber 2 is made of 304 stainless steel, and the inner test chamber 3 is made of polished aluminum plate, with a 25mm gap between them. The test platform 4 is a cylindrical copper platform with a diameter of 25mm and a height of 35mm. The first thermoelectric cooler 6 and the second thermoelectric cooler 7 are TEC1-12706 type, with their cold sides attached to the upper and lower surfaces of the test platform 4 via thermally conductive silicone grease, and their hot sides connected to independent aluminum heat sink fin assemblies. The heater 5 is a 60W ceramic heating element attached to the inner chamber wall. The external fan 14 is an 8025 fan, which blows air to dissipate heat from the two heat sink fin assemblies. The internal fan 13 is a 4010 fan, which promotes air circulation within the inner chamber. The first temperature sensor 15 is a PT100, embedded in the test platform 4, used to measure the LED substrate temperature; the second temperature sensor 16 is a K-type thermocouple, placed in the air of the inner test chamber 3, used to measure the LED ambient temperature; and the third temperature sensor 17 is a PT100, placed in the air of the outer test chamber 2. Electrical test interface 11 is a four-wire BNC interface, and optical test interface 12 is an SMA905 fiber optic interface. The three temperature controllers (8, 9, 10) are PID temperature controllers.

[0020] Example 2: The difference between this embodiment and embodiment 1 is that the second temperature sensor 16 is an MLX90614 infrared temperature sensor, which is fixed to the top wall of the inner test chamber 3 by a bracket, and the lens is facing the LED mounting position on the test platform 4 for non-contact measurement of LED junction temperature.

[0021] When rapid heating is required, the first temperature controller 8 is in control, causing the heater 5 to heat up, while the two thermoelectric cooling elements 6 and 7 operate at low power or remain in standby mode. When rapid cooling is required, the output of the heater 5 is turned off or reduced, and the second and third temperature controllers control the two thermoelectric cooling elements to operate according to preset curves. During the constant temperature phase, the three controllers work together at low power to maintain the set temperature. The internal fan 13 runs continuously to improve temperature uniformity, and the external fan 14 operates in sync with the temperature changes of the two sets of heat sinks.

[0022] Through the above embodiments, the LED lamp bead temperature testing device of this utility model can achieve the goals of stable structure, wide temperature control range and high measurement accuracy, and has broad application potential.

Claims

1. A temperature-changing testing device for LED beads, characterized in that, include: Base; An outer test chamber mounted on the base and an inner test chamber disposed inside the outer test chamber, with a heat insulation gap between the outer and inner test chambers; a test platform disposed in the center of the inner test chamber for placing the LED bead to be tested; a heater disposed inside the inner test chamber; a first thermoelectric cooling element and a second thermoelectric cooling element, the cold surfaces of which are respectively thermally connected to the upper and lower surfaces of the test platform, and the hot surfaces of which are respectively connected to independent heat sinks; A first temperature sensor is installed inside the test bench to detect the test bench temperature; a second temperature sensor is installed inside the inner test chamber, near the test bench, to detect the ambient temperature of the LED bead under test; a third temperature sensor is installed inside the outer test chamber to detect the outer test chamber temperature; a first temperature controller is signal-connected to the first temperature sensor and the heater; a second temperature controller is signal-connected to the second temperature sensor and the first thermoelectric cooler; and a third temperature controller is signal-connected to the third temperature sensor and the second thermoelectric cooler.

2. The LED lamp bead temperature testing device according to claim 1, characterized in that, The test stand is a copper test stand.

3. The LED lamp bead temperature testing device according to claim 1, characterized in that, The surface of the test bench is covered with a layer of highly thermally conductive silicone grease.

4. The LED lamp bead temperature testing device according to claim 1, characterized in that, The radiator is an aluminum heat sink fin assembly.

5. The LED lamp bead temperature testing device according to claim 1, characterized in that, The second temperature sensor is either a thermocouple attached to the substrate of the LED bead under test, or an infrared temperature sensor fixed to the top wall of the inner test chamber with its lens aligned with the test stage.

6. The LED lamp bead temperature testing device according to claim 1, characterized in that, The thermal insulation gap between the outer test chamber and the inner test chamber is 20mm to 30mm.

7. The LED lamp bead temperature testing device according to any one of claims 1-6, characterized in that, It also includes an electrical test interface and an optical test interface. The electrical test interface is electrically connected to the test bench, and the optical test interface is located outside the outer test chamber, directly above the LED bead under test. The outer test chamber and the inner test chamber have light-transmitting openings between the optical test interface and the LED bead under test.

8. The LED lamp bead temperature testing device according to claim 7, characterized in that, The optical testing interface is a flange-type fiber optic interface.

9. The LED lamp bead temperature testing device according to claim 7, characterized in that, The electrical test interface is a four-wire Kelvin BNC connector or an aviation plug.

10. The LED lamp bead temperature testing device according to claim 9, characterized in that, It also includes an external fan and an internal fan. The external fan is located inside the external test chamber and is used to dissipate heat from the radiators of the first thermoelectric cooling chip and / or the second thermoelectric cooling chip. The internal fan is located inside the internal test chamber and is used to promote air circulation within the internal test chamber.

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