Light irradiation test device

Abstract

To properly cool a LED light source in a light irradiation test device using the LED light source, and to keep illuminance therein.SOLUTION: A light irradiation test device 1 comprises: a sample stage 6 on which a sample 7 is loaded; at least one LED light source 8 that has a light emission surface 8a facing the sample stage 6, and irradiates the sample 7 with light from the light emission surface 8a; a thermal conductor 9 that is arranged so as to contact with a rear surface 8b of the LED light source 8; a cooling pipe 10 that is arranged across at least one part of the thermal conductor 9 on a rear surface 8a side of the LED light source 8, in which a coolant 11 flows; and a ventilator 12 that ventilates cooling air 13 into the LED light source 8. The cooling air 13 ventilated from the ventilator 12 is configured to be guided to the light emission surface 8a of the LED light source 8. A temperature of the cooling air 13 is equal to or less than that of the coolant 11.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a light irradiation test device used for light resistance tests and the like. [Background technology]

[0002] A light resistance test is a test in which a sample is irradiated with light from a light source to evaluate the degree of deterioration of the sample. In such a light resistance test, a light irradiation test device is used to irradiate the sample with light under various environments. Incandescent light bulbs, arc lamps, etc. have been used as light sources for conventional light irradiation test devices (see Patent Documents 1 and 2).

[0003] In recent years, lighting devices using LED light sources are becoming more and more popular. The materials that make up lighting devices using LED light sources need to be resistant to the light irradiated from the LED light source, so light resistance tests must be performed to select materials with excellent light resistance. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 61-3115 [Patent Document 2] JP 2018-169342 A Summary of the Invention [Problem to be solved by the invention]

[0005] When using an LED light source, heat accumulates inside the light source, and if the heat is not dissipated efficiently, problems such as malfunctions and shortened lifespan can occur.

[0006] However, if an LED light source is rapidly cooled using a refrigerant or the like, the amount of light (illuminance) of the LED light source decreases.

[0007] In view of the above, an object of the present invention is to provide a light irradiation test device that uses an LED light source, capable of appropriately cooling the LED light source and maintaining illuminance. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, the light irradiation test device of the present invention comprises a sample stage on which a sample is placed, at least one LED light source having an emitting surface facing the sample stage and irradiating light from the emitting surface to the sample, a thermal conductor arranged to contact the back surface of the LED light source opposite the emitting surface, a cooling pipe arranged on the back side of the LED light source sandwiching at least a portion of the thermal conductor and through which a cooling liquid passes, and a blower that blows cooling gas to the LED light source, and is configured so that the cooling gas blown from the blower is guided to the emitting surface of the LED light source.

[0009] According to the light irradiation test device of the present invention, the back side of the LED light source can be strongly cooled by the cooling liquid, and the light emitting surface side of the LED light source can be gently cooled by the cooling gas. Therefore, by combining cooling by the cooling liquid and cooling by the cooling gas, the LED light source can be appropriately cooled without being cooled excessively, so that the light irradiation test can be performed while maintaining high illuminance.

[0010] In addition, in the light irradiation test device according to the present invention, the air outlet of the blower may face the circumferential surface connecting the light-emitting surface and the back surface of the LED light source. In this way, the cooling gas blown from the blower can be guided from the circumferential surface side of the LED light source to the light-emitting surface side. In this case, if the edge of the air outlet on the sample stage side is located closer to the sample stage than the light-emitting surface of the LED light source, the cooling gas blown from the blower can be reliably guided to the light-emitting surface of the LED light source. In addition, if the edge of the air outlet on the opposite side to the sample stage is located on the opposite side to the sample stage than the thermal conductor, the back side of the LED light source can also be cooled by the cooling gas blown from the blower. In other words, the entire light source chamber in which the LED module having the LED light source, the thermal conductor, and the cooling pipe is arranged can be cooled, so that the cooling efficiency of the LED light source can be further improved.

[0011] In addition, in the light irradiation test device according to the present invention, a partition member that transmits light may be further disposed between the LED light source and the sample stage. In this way, the light source chamber in which the LED module is disposed and the test chamber in which the sample stage is disposed are separated by the partition member, so that the cooling efficiency of the LED light source by the cooling pipe and the blower can be further improved. Effect of the Invention

[0012] According to the present invention, in a light irradiation test device using an LED light source, the LED light source can be appropriately cooled to maintain illuminance. [Brief description of the drawings]

[0013] [Figure 1] FIG. 2 is a cross-sectional view of a light irradiation test device according to the first embodiment. [Diagram 2] FIG. 13 is a cross-sectional view of a light irradiation test device according to a modified example of the first embodiment. [Diagram 3] FIG. 11 is a cross-sectional view of a light irradiation test device according to a second embodiment. [Figure 4] FIG. 11 is a cross-sectional view of a light irradiation test device according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] (Embodiment 1) The light irradiation test apparatus 1 according to the first embodiment will be described below with reference to FIG.

[0015] As shown in Fig. 1, the inside of a housing 2 of a light irradiation test device 1 is, for example, divided into a test chamber 4 and a light source chamber 5 by a partition member 3 that transmits the irradiated light. The housing 2 may be made of, for example, stainless steel. The partition member 3 may be made of, for example, heat-resistant glass. In this embodiment, in the vertical direction, the test chamber 4 is located on the lower side and the light source chamber 5 is located on the upper side.

[0016] A sample stage 6 is arranged inside the test chamber 4, and a test sample 7 is placed on the sample stage 6 during a light irradiation test. The sample stage 6 is preferably a member having a plurality of through holes, such as a wire mesh or an expanded metal. Such a member can suppress heat accumulation in the sample stage 6, and therefore suppress heat conduction from the sample stage 6 to the placed sample 7, thereby suppressing the temperature effect on the sample 7. The sample stage 6 may also be provided with a means for fixing the sample 7, such as a suction means. The sample stage 6 may be held by a holding member (not shown) provided at the bottom of the test chamber 4, for example. Alternatively, hooks for adjusting the position of the sample stage 6 may be provided on both of the opposing inner wall surfaces of the test chamber 4, and the sample stage 6 may be supported on the hooks.

[0017] At least one LED light source 8 is disposed inside the light source chamber 5 for irradiating the sample 7 with light through the partition member 3. The LED light source 8 is disposed such that a light emitting surface 8a of the LED light source 8 faces the sample stage 6. In this embodiment, the light emitting surface 8a of the LED light source 8 is set to be parallel to a horizontal plane.

[0018] The LED light source 8 may be, for example, an LED chip such as COB (chip on board) or SMD (surface mounted device), but it is preferable to use COB for light irradiation tests that require particularly high illuminance. A single LED light source 8 may be used, but a plurality of LED light sources 8 may be used to perform light irradiation tests with higher illuminance. In the latter case, a plurality of LED light sources 8 may be arranged in a matrix. The wavelength of light irradiated from the LED light source 8 may be appropriately selected according to the environment in which the sample 7 is used. For example, when indoor use is assumed, an LED light source 8 that irradiates light in the visible light region (wavelength 380 nm to 780 nm) may be selected.

[0019] A thermal conductor 9 is disposed so as to be in contact with the rear surface 8b (the surface opposite to the light emitting surface 8a) of the LED light source 8. The material constituting the thermal conductor 9 is not particularly limited as long as it has high thermal conductivity, but aluminum, for example, may be used in terms of cooling efficiency. The thermal conductor 9 is held by a holding member (not shown) provided on, for example, the side wall or ceiling of the light source chamber 5. The LED light source 8 is attached to the thermal conductor 9.

[0020] A cooling pipe 10 is arranged on the rear surface 8b side of the LED light source 8, sandwiching at least a portion of the thermal conductor 9. A cooling liquid 11, such as cooling water, flows through the cooling pipe 10. The cooling pipe 10 is connected to a refrigerator (not shown) arranged outside the housing 2 in a circulating manner. In this embodiment, as an example, the cooling pipe 10 is embedded in the thermal conductor 9 along the arrangement of the LED light sources 8. The temperature of the cooling liquid 11 can be adjusted depending on the refrigerator used, but may be set to, for example, about 28 to 32°C.

[0021] A first air outlet 12a of a first air blower 12 such as a blower fan is provided on a side wall of the light source chamber 5. That is, in this embodiment, the first air outlet 12a faces the peripheral surface of the LED light source 8 (the surface connecting the light emitting surface 8a and the back surface 8b). A main body (not shown) of the first air blower 12 is disposed outside the housing 2, and an air blower pipe extends from the main body to the first air outlet 12a. An exhaust port (not shown) is provided on a side wall or ceiling of the light source chamber 5.

[0022] The first fan 12 blows cooling gas 13, such as cooling air, to the LED light source 8. The first fan 12 may have a temperature adjustment function. The temperature of the cooling gas 13 can be adjusted by the first fan 12 used, and may be set to, for example, about 25 to 35°C.

[0023] The light irradiation test device 1 of this embodiment is configured so that the cooling gas 13 blown from the first blower 12 is guided to the light emitting surface 8a of the LED light source 8. Specifically, the edge of the first blower 12a of the first blower 12 on the test chamber 4 side (i.e., the sample stage 6 side) is located closer to the sample stage 6 than the light emitting surface 8a of the LED light source 8. For example, the edge of the first blower 12a on the sample stage 6 side is located closer to the sample stage 6 by a distance d in the vertical direction than the light emitting surface 8a of the LED light source 8. Note that the edge of the first blower 12a on the opposite side of the test chamber 4 (i.e., the opposite side of the sample stage 6) is located closer to the sample stage 6 than the thermal conductor 9.

[0024] A second air outlet 14a of a second air blower 14 such as a blower fan is provided on the side wall of the test chamber 4 to maintain the inside of the test chamber 4 at a predetermined temperature. A main body (not shown) of the second air blower 14 is disposed outside the housing 2, and an air blowing pipe extends from the main body to the second air outlet 14a. An exhaust port (not shown) is provided on the side wall or bottom of the test chamber 4. The second air blower 14 blows gas 15 such as air to the sample 7. The second air blower 14 may have a temperature adjustment function. The temperature of the gas 15 can be adjusted by the second air blower 14 used, but may be set to, for example, about 60 to 120° C. when the LED light source 8 is turned on.

[0025] Although not shown, the light irradiation test device 1 may have an operation unit (such as a touch panel) on the outer wall surface of the housing 2 or the like for operating the LED light source 8, the fans 12, 14, and the like.

[0026] According to the light irradiation test device 1 of the present embodiment described above, the back surface 8b side of the LED light source 8 can be strongly cooled by the cooling liquid 11, and the light emitting surface 8a side of the LED light source 8 can be gently cooled by the cooling gas 13. Therefore, by combining the cooling by the cooling liquid 11 and the cooling by the cooling gas 13, the LED light source 8 can be appropriately cooled without being excessively cooled, so that the light irradiation test can be performed while maintaining high illuminance. Furthermore, it is possible to prevent the LED light source 8 from accumulating heat and breaking down. In particular, when the illuminance of the LED light source 8 is about 3 million lux or more, the LED light source 8 accumulates heat and becomes hot, so cooling by the cooling liquid is required, so the above-mentioned effect of the light irradiation test device 1 of the present embodiment is remarkable.

[0027] In addition, in the light irradiation test device 1 of this embodiment, the air outlet 12a of the air blower 12 faces the circumferential surface connecting the light emitting surface 8a and the back surface 8b of the LED light source 8, so that the cooling gas 13 blown from the air blower 12 can be guided from the circumferential surface side of the LED light source 8 to the light emitting surface 8a side. In this case, the edge of the air outlet 12a on the sample stage 6 side is located closer to the sample stage 6 than the light emitting surface 8a of the LED light source 8, so that the cooling gas 13 blown from the air blower 12 can be reliably guided to the light emitting surface 8a of the LED light source 8. In addition, the edge of the air outlet 12a opposite to the sample stage 6 is located on the opposite side of the sample stage 6 than the thermal conductor 9, so that the back surface 8b side of the LED light source 8 can also be cooled by the cooling gas 13 blown from the air blower 12. In other words, the entire light source chamber 5 in which the LED module having the LED light source 8, the thermal conductor 9, and the cooling tube 10 is arranged can be cooled, so that the cooling efficiency of the LED light source 8 can be further improved.

[0028] Furthermore, in the light irradiation test apparatus 1 of this embodiment, a partition member 3 that transmits light irradiated from the LED light source 8 is disposed between the light source chamber 5 and the test chamber 4 (i.e., between the LED light source 8 and the sample stage 6), so that the cooling efficiency of the LED light source 8 by the cooling pipe 10 and the blower 12 can be further improved.

[0029] In this embodiment, the temperature of the cooling gas 13 may be set to be equal to or lower than the temperature of the cooling liquid 11. In this way, condensation is less likely to occur in the light source chamber 5, and the occurrence of breakdowns in the LED light sources 8 and the like can be suppressed. For example, the temperatures of the cooling gas 13 and the cooling liquid 11 may be set to the same temperature of 30° C. In addition, in order to further suppress the occurrence of condensation in the light source chamber 5, a dehumidifying means such as a dehumidifier may be provided in the light source chamber 5.

[0030] (Modification of the first embodiment) Hereinafter, a light irradiation test apparatus 1 according to a modified example of the first embodiment will be described with reference to Fig. 2. In Fig. 2, the same components as those in the first embodiment shown in Fig. 1 are denoted by the same reference numerals.

[0031] The light irradiation test apparatus 1 of this modified example differs from the first embodiment in that the test chamber 4 and the light source chamber 5 are arranged side by side in the horizontal direction, as shown in Fig. 2. Here, the light emitting surface 8a of the LED light source 8 is set to be parallel to the vertical plane. In other words, the LED light source 8 irradiates light in the horizontal direction.

[0032] The light irradiation test apparatus 1 of this modified example described above can also provide the same effects as those of the first embodiment.

[0033] (Embodiment 2) Hereinafter, the light irradiation test device 1 according to the second embodiment will be described with reference to Fig. 3. In Fig. 3, the same components as those in the first embodiment shown in Fig. 1 are denoted by the same reference numerals.

[0034] The light irradiation test apparatus 1 of this embodiment differs from embodiment 1 in that, as shown in FIG. 3, the edge of the first air outlet 12a of the first blower 12 on the test chamber 4 side (i.e., the sample stage 6 side) is located on the opposite side of the sample stage 6 from the light emitting surface 8a of the LED light source 8, while a guide member 21 is provided between the LED module having the LED light source 8, the thermal conductor 9, and the cooling tube 10, and the first air outlet 12a, for guiding the cooling gas 13 blown from the first blower 12 to the light emitting surface 8a of the LED light source 8.

[0035] The light irradiation test apparatus 1 of this embodiment described above can also provide the same effects as those of the first embodiment.

[0036] In this embodiment, instead of providing the guide member 21, the air blower duct of the first blower 12 may be extended into the light source chamber 5, and the first air blower port 12a may be disposed near the light emitting surface 8a of the LED light source 8.

[0037] (Embodiment 3) Hereinafter, the light irradiation test apparatus 1 according to the third embodiment will be described with reference to Fig. 4. In Fig. 4, the same components as those in the first embodiment shown in Fig. 1 are denoted by the same reference numerals.

[0038] The light irradiation test device 1 of this embodiment differs from the first embodiment in that, as shown in Fig. 4, the first air outlet 12a of the first air blower 12 is provided on the ceiling of the light source chamber 5, while a guide member 22 is provided between the LED module having the LED light source 8, the thermal conductor 9, and the cooling pipe 10 and the side wall of the light source chamber 5 to guide the cooling gas 13 blown from the first air outlet 12 to the light emitting surface 8a of the LED light source 8. That is, the cooling gas 13 blown out from the first air outlet 12a on the ceiling of the light source chamber 5 travels along the surface of the thermal conductor 9 opposite to the LED light source 8 toward the side wall of the light source chamber 5, and reaches the light emitting surface 8a of the LED light source 8 by bypassing the LED module by the guide member 22.

[0039] The light irradiation test apparatus 1 of this embodiment described above can also provide the same effects as those of the first embodiment.

[0040] In this embodiment, the air duct of the first blower 12 may penetrate the ceiling of the light source chamber 5 and terminate at the first air outlet 12a, or may penetrate the side wall of the light source chamber 5 and extend along the ceiling of the light source chamber 5 to near the center of the ceiling and terminate at the first air outlet 12a. That is, in this embodiment and other embodiments (including modified examples), the path of the air duct from the main body of the first blower 12 to the first air outlet 12a and the position where the air duct penetrates the housing 2 are not particularly limited.

[0041] Also, a light resistance testing method is provided for testing the light resistance of a sample 7 using the light irradiation testing device 1 according to each of the above-mentioned embodiments (including the modified examples). According to this light resistance testing method, it is possible to irradiate high-intensity light from the LED light source 8, so that the light resistance can be evaluated in a short period of time. Furthermore, if the wavelength of the light irradiated from the LED light source 8 is in the visible light region (wavelength 380 nm to 780 nm), the light resistance of the sample 7 for indoor use can be appropriately evaluated.

[0042] Although the embodiments and modifications have been described above, it will be understood that various modifications of form and details are possible without departing from the spirit and scope of the claims. Moreover, the above embodiments and modifications may be appropriately combined or substituted as long as the functionality of the subject matter of this disclosure is not impaired. Furthermore, the descriptions "first", "second", ... described above are used to distinguish the words to which these descriptions are attached, and do not limit the number or order of the words. [Explanation of symbols]

[0043] 1 Light irradiation test device 1 2. Housing 3 Partitioning material 4. Test Room 5 Light source room 6 Sample stage 7. Sample 8 LED light sources 8a Light-emitting surface 8b Back 9. Thermal Conductors 10 Cooling pipe 11 Coolant 12 1st blower 12a First ventilation outlet 13 Cooling Gas 14 2nd blower 14a Second ventilation outlet 15 Gas 21 Guide member 22 Guide member

Claims

1. A sample stage on which a sample is placed; at least one LED light source having a light emitting surface facing the sample stage and irradiating light from the light emitting surface to the sample; a heat conductor arranged to be in contact with a rear surface of the LED light source opposite the light emitting surface; a cooling pipe arranged on the rear surface side of the LED light source to sandwich at least a portion of the thermal conductor, the cooling pipe passing a cooling liquid; a blower that blows a cooling gas to the LED light source, The cooling gas blown from the blower is configured to be guided to the light emitting surface of the LED light source, A light irradiation test device, wherein the temperature of the cooling gas is equal to or lower than the temperature of the cooling liquid.

2. an air outlet of the air blower is provided in a side wall of a light source chamber in which the LED light source is arranged and is directly connected to a main body of the air blower; The light irradiation test device according to claim 1 , wherein the cooling gas is blown directly to the LED light source from the blower port.

3. The light irradiation test device according to claim 1 , further comprising a guide member provided inside a light source chamber in which the LED light source is disposed, the guide member directing the cooling gas to the light emitting surface of the LED light source.

4. 4. The light irradiation test device according to claim 1, wherein the temperature of the cooling gas when cooling the LED light source is 25 to 35.degree.

5. The LED light source is a chip-on-board LED chip; The light irradiation test device according to any one of claims 1 to 4, wherein the illuminance of the LED light source is 3 million lux or more.

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