TWI436104B - Solar light simulation device with light source module and the simulation test device - Google Patents

Description

Light source module for solar light simulation device and the same

The invention relates to a light source module for a solar light simulation device and a solar light simulation test device using the same.

In the current common clean energy, the use of solar cells to generate electricity has become an extremely important part. The power generation efficiency of solar cells is currently the most important indicator for measuring the quality of solar cells; therefore, the device for testing the efficiency of solar cell power generation must be very accurate; and the most important component of the test device is the source of sunlight. Since the spectrum and illuminance of sunlight vary with geographical location, season, cloud distribution, and air quality, in order to simplify and standardize the test environment, AM-1.5G is recommended by the US IEC or JIS. The standard is to make an analog light source.

In this standard, three main indicators such as the spectral distribution deviation of the simulated light source, the uniformity of illumination, and the stability of the illumination are specified; and the light source is classified into three grades A, B, and C according to the amount of deviation, and the current solar cell industry The accepted standard is Class A. The spectral deviation of this level must be less than ±25%, the illumination unevenness must be less than ±2%, and the illumination instability must be less than ±2%. Since the solar light intensity at AM-1.5G is about 1000 W/m ² and almost parallel light, as the light source of the solar simulator, in addition to the above three requirements of Class A, the light intensity and parallel The Collimation Angle is also an important indicator. Generally, the output light intensity must be above 1000 W/m ² and the concentrating angle is within ±3 degrees.

Because Xe (Xenon Light) bulbs emit light closer to sunlight and the light output energy is also large enough, in the past, solar light simulation devices used Xe bulbs as the light source, but to measure the actual spectral distribution, To meet the Class A requirements, you still need to use complex optical filters.

In recent years, various types of solar cells have been continuously innovated, and the solar light simulation devices used for testing require a light source with a more accurate spectrum. Therefore, some manufacturers have introduced a composite solar light simulation device using a mixture of Xe bulbs and halogen metal bulbs, but the price is also Extremely expensive. In addition, due to the inspection of the solar module, the area of the object to be tested is often large, and the light source needs to be distributed to a very large area to be successfully inspected; the Xe bulb diverging from the four sides is used as a light source to obtain a uniform illumination. And distributed to a wide range, the test distance between the bulb and the object to be tested needs to be opened to a very large size, causing the test equipment to be bulky and inconvenient to test; and the luminous intensity of the Xe bulb itself is difficult to reach after being dispersed to a large area. Strength, causing limitations in use.

On the other hand, in recent years, the power of LEDs has continued to increase, and LEDs of different wavelength bands have appeared one after another. Therefore, the use of LEDs as a light source for solar simulators has gradually become feasible and has been paid attention to. At present, the existing laboratory LED solar light simulation device is composed of a plurality of sets of LEDs 100 of different wavelength bands, for example, a 6×6 LED matrix, to form a module 10, and then, for example, four modules 10 form an area. For larger devices, the center wavelengths of the 36 LEDs 100 are selected from the range of 380 nm to 1200 nm of the actual solar spectrum, and each of the optical powers is also controlled within the required standard solar intensity.

Since the collimation angle required by the solar light simulation device is very small, each LED 100 must select a Lamp type LED with a small illumination angle, and its light field half power angle is within ±5 degrees. Also, because the light field half power angle of the bullet-type LED is very small, in the module 10, the light mixing effect of the LEDs of different bands is not good, so the uniformity of the wavelength distribution is very poor, and the Class A solar simulation The 98% uniformity required by the device is quite different, so so far, there has not been an LED solar simulator that can reach Class A.

SUMMARY OF THE INVENTION One object of the present invention is to provide a light source module for a solar light simulation device that can provide a large area uniform beam to a Class A level.

Another object of the present invention is to provide a light source module for a solar light simulation apparatus that uses a plurality of LED elements to provide a spectrum close to standard sunlight.

Still another object of the present invention is to provide a light source module for a solar light simulation device that can be combined by a plurality of modules to continuously expand an illumination area.

Still another object of the present invention is to provide a light source module for a solar light simulation apparatus which uses an LED element and which can reduce cost.

It is still another object of the present invention to provide a solar light simulation apparatus that conforms to the Class A standard.

A light source module for a solar light simulation device according to the present invention includes: a plurality of light emitting diodes each having a center wavelength, and a center wavelength of each of the light emitting diodes is distributed at at least three mutually different wavelengths; And a set of light homogenizers, comprising: one having at least six surfaces, wherein at least one of the light-incident surfaces formed with a plurality of transparent holes corresponding to the light-emitting diodes, and a transmittance of less than 50% and a reflectance greater than 50 a uniform light-emitting cavity of the light-emitting surface of the light-emitting surface, wherein the cavity is made of a light-transmissive material, and all the surfaces except the light-emitting surface are formed with a reflective layer for reflecting the light beam from the inside of the cavity toward the inside of the cavity. Providing at least one light beam disposed outside the at least one light incident surface for diverging the light beam from the light emitting diode, such that the light beam diverges at an angle of a refraction angle greater than an incident angle thereof through the transparent hole into the light homogenizing cavity; And a piece disposed on the outer side of the light-emitting surface for converging the uniform light beam from the light-shaping cavity, so that the light-homogenizing beam is away from the uniform light cavity at a refraction angle smaller than the incident angle thereof Convergence angle piece.

The solar light simulation test device made by using the above light source module is for measuring the photoelectric performance of the solar cell to be tested, and the simulation test device comprises: at least one light source module, including: a plurality of light-emitting diodes having a plurality of central wavelengths a polar body; and a set of light homogenizers, comprising: one having at least six surfaces, at least one of which has a plurality of light incident surfaces corresponding to the transparent holes of the light emitting diodes, and a transmittance of less than 50% and reflection a uniform light-emitting cavity having a light-emitting surface with a rate greater than 50%, the interior of the cavity being a light-transmitting material, and all but the light-emitting surface are formed to reflect the light beam from the interior of the cavity toward the interior of the cavity a reflective layer; at least one set disposed outside the at least one light incident surface for diverging a light beam from the light emitting diode, wherein the light beam passes through the transparent hole into the uniform light cavity at a refraction angle greater than an incident angle thereof a divergent sheet of the body; and a set of uniform light beams disposed outside the light exiting surface for converge from the homogenizing cavity such that the homogenizing beam is at a refraction angle smaller than an incident angle thereof The angle of convergence cavity dodging sheet; and a test set for measuring the solar cell is irradiated by the light source module of the output electrical signal of the test module.

Since the light source module for the solar light simulation device disclosed in the present invention transmits the light beam entering the resonant cavity back and forth in the cavity through an "optical cavity", except for a small proportion, the light beam can escape, most of the light beam will be Uniform mixing in the repetitive reflection process, and using a set of angular divergence pieces and a set of angle convergence pieces, the deflection angle of the light beam entering the optical cavity is increased, so that the light beam that has not left the light surface is reflected back at each time. When entering the light surface, the horizontal distance of the passing becomes larger, that is, the mixing range becomes larger, and the uniformity of the light is increased. Conversely, when the beam is separated from the light emitting surface, the complementary angle convergence plate acts, and the deflection angle is reversed. So that the beam of light exits substantially back to near the collimation direction.

In addition, by emitting light from a plurality of LEDs, the total light output is close to the spectrum of the standard sunlight; and since the light source module disclosed in the present invention has been modularized, it can be used in combination with a plurality of modules, thereby easily illuminating the solar light simulation device. The area is increased to meet the testing needs of different sizes of solar cells, thus achieving all of the above objectives.

The foregoing and other objects, features, and advantages of the invention are set forth in the <RTIgt;

In the preferred embodiment of the present invention, as shown in FIG. 2, a four-group LED module 10' similar to the above is used as a light source. In this example, 36 LEDs 100' each having a different center wavelength are used. A plurality of light-emitting diode modules 10' are formed together, and the four-piece module 10' is disposed in a plane in the same direction to emit light. In the lower part of the figure, a set of light-shaders 2 is further disposed, in this example Four transparent plastic parallelepiped "optical cavities" as shown in FIG. 3 are used as the homogenizing cavity 20, and each of the homogenizing cavities 20 corresponds to one of the above-mentioned modules 10'.

For convenience of description, the surface of the uniformizing cavity 20 facing the module 10' is referred to as a light incident surface 22, and a light reflecting surface 22 is plated with a highly reflective metal film 222, and a plurality of diameters are formed at the metal film 222. 2 mm, and corresponding to the transparent hole 220 of the LED 100', respectively, so that the light-incident surface 22 has a high reflectivity substantially close to 100% except for the transparent hole 220. Of course, the metal film can also be multi-layered. A highly reflective structure such as a film is substituted.

In order to increase the light intensity entering the uniform cavity 20, a set of concentrating lens arrays 3 are disposed between the module 10' and the light incident surface 22, and the concentrating lens array 3 is formed at positions corresponding to the light beams emitted by the LEDs 100'. There is a condensing mirror 30, so that the condensing mirrors 30 in this example have a one-to-one correspondence with the LEDs 100', and the beams of the LEDs 100' can be focused to the corresponding transparent holes 220 for smooth incident to the uniform light. In the cavity 20.

The uniformizing cavity 20 of the present example is formed with a partially reflective, partially transmissive (Partial Transmission) reflective layer 242 having a reflectance of about 90% and a transmittance of about 10% on the bottom surface of the light incident surface 22. The light beam from the homogenizing cavity 20 can be slightly emitted, so it is called the light exiting surface 24. On the four peripheral walls except the light-incident surface 22 and the light-emitting surface 24, a reflective layer having a reflectance close to 100% is formed, so it is called a surrounding reflective surface 26. Similarly, the structure may be a multilayer film on a glass sheet or The metal film is plated to achieve high-efficiency reflection; of course, the glass material described above can also be changed to a high-transmission plastic material such as acrylic, polycarbonate (PC) and the like.

Therefore, the light beam entering the uniform cavity 20 from the light-incident surface 22, except for a small amount transmitted by the light-emitting surface 24, is forced to be reflected back and forth in the cavity as indicated by the arrow in FIG. 2, at different center wavelengths. The bundle of LEDs 100' is illuminated to be mixed. Therefore, in the "optical resonator", the band energy distribution at each spatial point is very uniform, and the illuminance is also very uniform.

The light beam emitted by the LED 100' passes through the condensing mirrors 30, and is designed by using the F value of the lens. The light divergence angle can be designed within 3 to 5 degrees. In this example, the traveling directions are parallel to each other. Go down from the top of the diagram. Since the light beam of each LED 100' has only a small divergence angle, in order to improve the light mixing effect, a micro-prism sheet 224 as shown in FIG. 4 is further disposed above the light incident surface 22 as An angle divergence sheet; the microcolumn sheet is composed of a column, in this example, a pitch P of about 50 μm and a corner angle of 90 degrees. After the light beam passes through the micro-column sheet 224, the traveling direction is deflected by the angle θ, and then enters the "optical resonator" by the transparent hole 220 remaining on the light-incident surface 22. And at the light-emitting surface, a micro-column piece 244 which is mirror-symmetrical to the angular divergence piece is also provided as an angle convergence piece.

If the direction of travel of the light passing through the micro-column sheet 224 is as shown in FIG. 5, the light beam will be clockwise deflected by an angle of -θ from the right side of the micro-column sheet 224, and as shown in FIG. The left side of the "optical resonator" is reflected by the reflection surface 26, and then travels to the light exit surface 24, at which time 90% is reflected back to the "optical resonator", and the other 10% is transmitted downward through the light exit surface 24, because there is a light exit surface 24 below The micro-column piece 244 whose direction is reversed is reversed due to the direction of the column. When a beam enters at an angle θ, the exit angle will be turned to an angle of 0 degree, and the beam will be emitted. The yaw angle θ of the beam is restored to 0 degree output.

Similarly, as shown in Fig. 6, the light beam entering through the left side slope of the micro-column sheet 224 is deflected counterclockwise by +θ angle; and as also shown in Fig. 2, 10% of the light energy is transmitted through the light-emitting surface 24 The face 24 is downward, and then the micro-column piece 244 is returned to the zero-degree angle. Since the "optical cavity" in this example is a parallelepiped cavity, the beams are in the "optical cavity". Although the reflection is repeated multiple times, after the micro-column piece 244 which is inverted as the angle convergence piece, the angle of the emitted light can be reduced to an angle close to 0 degree; thereby, the beam collecting angle of the light source module is both Close to zero and parallel to each other, the angle requirement of the beam of light emitted by the light source can be achieved.

When the corner angle is 90 degrees, the deflection angle θ is about 30 degrees. When the corner angle is 60 degrees, the deflection angle θ is about 40 degrees. Since the distance between the turns is very small, only about 50 μm, so incident. If the beam has a diameter of 1 mm = 1000 μm, the emitted light will appear as shown in Fig. 7, and two beams of θ angles will appear. Since the mast has a uniform columnar shape in the y-axis direction of the paper, the incident light has a deflection angle only in the x-axis direction in the left-right direction of the drawing. If the y-axis direction deflection angle is required, as shown in Fig. 8, it is necessary to add a micro-column piece 226 in the y-axis direction. The two pieces overlap each other vertically to achieve the function of biasing both the x and y axes. Therefore, an incident beam, after passing through the two micro-column segments, will produce two clockwise and counter-clockwise deflecting beams in the x-axis direction, and the y-axis direction will produce two deflections of the paper surface and the offset paper surface. Therefore, the deflection directions are arranged and combined to generate four beams in different directions.

The main purpose of deflecting the incident angle of the incident beam of the LED by 0 degrees to the angle θ by using the micro-column sheet is to increase the light-mixing effect of the beam in the "optical resonator". The principle shown in Figure 9, when a light beam ₁ starts to travel at an incident angle θ by the point P in the "optical cavity", respectively, at the point _{P 2, P 3, P 4} , P 5 by multiple reflections, because the incident The angle is θ. When the height of the "optical resonator" is h, the distance of the beam from P ₁ to P ₅ is 2 h ‧ tan θ in the horizontal direction of the drawing, and the total distance L 2 is 2 sec θ. If the incident angle θ=0, the beam will only be reflected back and forth between the light incident surface and the light exit surface. The light beam is distributed in the upper and lower straight lines, and the distribution range that can be covered is extremely small; relatively, when the incident angle θ is 30 degrees, the light beam Will cross in the horizontal direction (2 3) h/3, that is, the range of the illumination surface covered by the beam will be very large.

When the beam with a large incident angle θ is traveled from P ₁ to P ₅ and then reflected again in the optical cavity, its path has been changed and will pass through different positions. If the beam can be repeatedly reflected, The trajectory can undoubtedly cover the entire optical cavity, that is, the entire illuminating surface can be made to contribute light; thus, the beam distribution at different center wavelengths will be more uniform. In addition, since the beam diverges with its solid angle, the spot size of the beam will increase as the path length increases, and the relationship between the spot diameter and the travel distance L is D. LΔβ, where L is the path distance of the beam and Δβ is the beam divergence angle. Therefore, the distribution of the light beam in the "optical resonant cavity" will be more uniform due to the larger the total path distance.

Therefore, when the incident angle θ is larger, the larger the total travel distance L is, and the larger the point size D of the beam divergence, the better the degree of light mixing. For example, when h = 300 mm of the "optical cavity" and θ is chosen to be 30 degrees, Δβ = ±3 degrees, the beam starts from the starting point P ₁ and passes through a series of reflections to reach the P ₅ position. 70 mm. That is, when the light beam reciprocates in the "optical resonant cavity", the light spot size will increase by 70 mm when each row returns to the light surface through the light exiting surface. Therefore, if the above-mentioned round-trip reflection is performed 5 times, the light is originally incident. The beam that enters the homogenizing cavity as a point source will expand its spot diameter to 350 mm. The spot diameter of a single beam is enough to cover the entire "optical cavity", so the light mixing effect can be seen.

For the sake of explanation, it is defined here that the light beam enters from the light incident surface, is reflected by the light exit surface, and returns to the light incident surface for reflection. It is called a "complete reflection", and the peripheral total reflection after two "optical resonators" Assuming that the reflection coefficient is α ₁ , one of the light passing through the light-emitting surface transmits light, assuming that the light-emitting rate is r, the reflectivity is (1-r), and then the light-reflecting surface is reflected once, assuming that the average reflectance is α. ₂ , so the light intensity after a complete reflection of the beam I ₁ =I ₀ ‧α ₁ ² (1-r)α ₂ , for example, when α ₁ =98%, r=10%, α ₂ =98%, then I ₁ = 0.85 I _0, if after five "fully reflected" through the beam intensity there I ₅ = 0.44 I ^_0.. In the above example, the light beam in the "optical resonator" can be regarded as effective "complete reflection" from 5 to 6 times. If the light beam enters the "optical resonator", since four beams of different deflection angles have been calculated after passing through the two micro-column sheets, the LED beam will be generated in the "optical resonator". 20~24 times of complete reflection, so that the full blending can be achieved.

When a plurality of LED arrays of different bands are used to form a light source module, for example, a 6×6 matrix of three centimeters square, wherein each LED is composed of a bullet-shaped LED with a small enough beam angle. The light source module 1' of the plurality of LED matrices can be further combined into a larger-area light source as shown in FIG. 10, and irradiated to the lower solar cell, for the test module 90 to measure the output voltage and current, thereby Obtain the photoelectric conversion performance of the solar cell to be tested. In this way, it is completely flexible to respond to the needs of the test, and there is no need to worry about the increase in the size of the object to be tested, and the test equipment cannot be troubled. Even if the light is slightly dimmed at the boundary of the splicing of the light source modules, the distance between the object and the object to be tested is at least several centimeters compared to the thickness of the homogenizer of 1 to 2 mm, so the splicing boundary is dimmed. When it is irradiated to the object to be tested, it will not cause any influence.

Of course, as can be easily understood by those skilled in the art, the above-mentioned angular divergence sheet is not limited to a micro-column sheet of a single columnar structure, as shown in FIG. 11, a micro-turn having a plurality of cone portions may also be used. The column piece serves as an angle divergence piece and an angle convergence piece, and each of the cone portions respectively corresponds to a transparent hole of the light incident surface, so that the incident light can be diverged and converged at a radially symmetrical deflection angle; The columnar arrangement direction is vertical, and the two columnar micro-column sheets are stacked, which can meet the requirements of the present case.

Through the above design, the light source module disclosed in the present invention can use the LED to manufacture a light source module for a Class A solar simulation device with uniform beam and low light exit angle; and by splicing multiple light source modules, it can be treated accordingly The area of the measuring object is increased, and the elasticity of use is good; and the plurality of LED elements are used to combine the spectrum close to the standard sunlight; and the cost of the overall light source module is greatly reduced, thereby manufacturing a more competitive market. The solar light simulation device achieves all of the above objectives.

However, the above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications according to the scope of the present invention and the description of the invention are still It is within the scope of the patent of the present invention.

10, 10’‧‧‧ modules

100, 100’‧‧‧LED

2‧‧‧Doe

20‧‧‧Homophonic cavity

22‧‧‧Into the glossy surface

222‧‧‧Metal film

220‧‧‧ transparent holes

3‧‧‧Concentrating lens array

30‧‧‧Condenser

242‧‧‧reflective layer

24‧‧‧Glossy

26‧‧‧ Surround reflection surface

224, 244, 226‧‧‧ micro-column

90‧‧‧Test module

1'‧‧‧Light source module

1 is a perspective view of an LED light source of a conventional solar light simulation device;

2 is a perspective view of a preferred embodiment of the present invention, illustrating the correspondence between the four groups of light emitting diode modules and the light homogenizer;

Figure 3 is a schematic view of the light homogenizer of the embodiment of Figure 2, illustrating the light-incident surface and the surface structure;

Figure 4 is a perspective view of the micro-column sheet of the embodiment of Figure 2 as an angular divergence sheet; Figures 5 to 7 are schematic views of the beam deflection of the micro-column sheet of Figure 4; Figure 8 is a stack of micro-column sheets of Figure 4 FIG. 9 is a schematic diagram showing the reflection of a light beam in a homogenizer, illustrating a "complete reflection" approach; FIG. 10 is a schematic diagram of a solar simulation device using the light source module of the embodiment of FIG. 2; and FIG. 11 is the present case A perspective view of the angular divergence sheet structure of the second preferred embodiment.

10’. . . Module

100’. . . led

2. . . Shaker

20. . . Uniform cavity

twenty two. . . Glossy surface

224. . . Micro-column

twenty four. . . Glossy surface

244. . . Micro-column

26. . . Surround reflection surface

3. . . Concentrating lens array

30. . . Condenser

Claims (10)

A light source module for a solar light simulation device, comprising: a plurality of light emitting diodes having a plurality of center wavelengths; and a set of light homogenizers, comprising: one having at least six surfaces, wherein at least one of the plurality is formed with a plurality of corresponding lights a light-incident surface of the transparent hole of the diode, and a light-shaping cavity having a light-emitting surface having a transmittance of less than 50% and a reflectance of more than 50%, wherein the light-receiving cavity is made of a light-transmitting material, and the light-emitting surface is removed In addition, all of the other surfaces are formed with a reflective layer for reflecting the light beam from the interior of the light homogenizing cavity toward the interior of the light homogenizing cavity; at least one set is disposed outside the at least one light incident surface for diverging from the above a light beam of the light emitting diode, such that the light beam passes through the transparent hole and enters the angle diverging sheet of the light homogenizing cavity at a refraction angle greater than the incident angle thereof; and a set is disposed outside the light emitting surface for convergence from the uniformity The uniform light beam in the optical cavity causes the uniform light beam to converge at an angle away from the uniformity of the uniformity. The light source module for a solar simulation device according to claim 1, wherein the at least one set of angular divergence sheets comprises two micro-column sheets each formed with parallel turns, and the two micro-column pieces It is arranged such that the arrangement direction of the 稜鏡 is vertically overlapped with each other. The light source module for a solar light simulation device according to claim 2, wherein the light homogenizing cavity has only one light incident surface, and the light incident surface is disposed parallel to the light emitting surface. The light source module for a solar simulation device according to claim 3, wherein the angle convergence piece is mirror-symmetrical to the angle divergence piece. The light source module for a solar light simulation device according to claim 1, wherein the at least one set of angles The divergence sheet is a piece of micro-column piece formed with a plurality of cone portions respectively corresponding to the transparent holes. The light source module for a solar light simulation device according to claim 1, wherein the light-emitting surface reflectance is greater than 85%, and the transmittance is less than 15%. For example, the light source module for a solar light simulation device according to the first, second, third, fourth, fifth or sixth aspect of the patent application, wherein the light homogenizing cavity is an insulating glass case. For example, the light source module for a solar light simulation device according to claim 1, 2, 3, 4, 5 or 6 wherein the uniform light cavity is a solid transparent plastic parallelepiped. The light source module for a solar light simulation device according to the first, second, third, fourth, fifth or sixth aspect of the patent application, wherein the light emitting diodes each have an illumination angle smaller than a predetermined solid angle, and the light source module is further A concentrating lens array is disposed between the light emitting diode and the at least one light incident surface. A solar light simulation test device for measuring photoelectric performance of a solar cell to be tested, the simulation test device comprising: at least one light source module comprising: a plurality of light emitting diodes having a plurality of center wavelengths; and a set of light homogenizers The method includes: a light-emitting surface having at least six surfaces, at least one of which forms a plurality of transparent holes corresponding to the light-emitting diodes, and a light-emitting surface having a transmittance of less than 50% and a reflectance of more than 50% The light cavity body has a light transmissive material inside, and all the surfaces except the light exiting surface are formed to reflect the light beam from the inside of the light homogenizing cavity toward the interior of the light homogenizing cavity. a reflective layer; at least one set disposed outside the at least one light incident surface for diverging from the light emitting diode a beam of light that causes the beam to pass through the transparent aperture through an angle of refraction greater than its angle of incidence into the uniform cavity of the homogenizing cavity; and a set of outside the light exiting surface for convergence from the homogenizing cavity a uniform light beam, such that the uniform light beam is away from the uniformity of the uniformity cavity by an angle of refraction smaller than the angle of incidence thereof; and a set of output electrical signals for measuring the solar cell to be tested to be illuminated by the light source module Test module.