JPH08235903A - Solar simulator - Google Patents

Abstract

PURPOSE: To obtain light having the spectrum similar to the solar radiation from the ultraviolet radiation to the infrared radiation by providing a mirror for selectively transmitting and reflecting different light from a plurality of light sources. CONSTITUTION: A xenon lamp 1 emits light from the lower right, transmits the light having the wavelength of 800nm or more including the bright line spectrum by using a cold mirror 2, and reflects ultraviolet light and the visible light having the wavelength of 800nm or less to an irradiation surface 7. A halogen lamp 3 irradiates from the upper left and transmits the light having the wavelength over 800nm by a sharp cut filter 5, and reflects the ultraviolet light and the visible light having the wavelength of 800nm or less. The light having the wavelength of 800nm or less, reflected from by the mirror 2 from the lamp 1 and the light having the wavelength over 800nm transmitted through the filter 5 from the lamp 3 are mixed to each other, so as to become the light having the spectrum similar to the solar radiation. Moreover, the infrared light is removed by making the light pass through a water tank 4, and the light can be made similar to the solar radiation to reach the ground surface.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a solar simulator having a spectrum similar to solar radiation from ultraviolet radiation to infrared radiation.

[0002]

Solar radiation includes ultraviolet radiation, visible light radiation, and infrared radiation. The solar simulator that reproduces solar radiation is the development and evaluation of a light energy conversion system that uses the sun, the cultivation and cultivation of plants and microorganisms that perform photosynthesis, the evaluation and inspection of the color field, the monitoring of changes in substances caused by solar radiation, etc. It is useful in a wide range of fields.

Solar radiation incident on the surface of the earth exhibits a spectral energy distribution as shown in the diagram of FIG. FIG. 3 shows a spectrum of solar radiation after passing through an air mass (atmospheric mass) of 1.5, where air mass means the thickness of the atmospheric layer through which the solar radiation passes, and 0.1, 1 Represented as .5, 2, etc. Various solar simulators have been developed so far in order to generate light having a spectrum similar to that of solar radiation. These were developed as solar simulators that can reproduce similar spectra only in the required fixed wavelength range.By using them properly for each purpose, simulation under solar radiation can be performed. There is. Therefore, conventionally, solar radiation has not been reproduced in the wavelength range from ultraviolet radiation to infrared radiation.

Conventionally, a xenon lamp, a metal halide lamp, a halogen lamp or the like has been used alone as a light source of a solar simulator. The spectra of light obtained from various light sources will be described below with reference to the wavelength-light energy diagrams of FIGS. 4 to 9, and the light from these light sources has their own spectra. .

The light spectrum of the halogen lamp is continuous light as shown in FIG. 4, and differs from that of solar radiation in that it does not contain much ultraviolet light and that the light energy has a maximum near 1000 nm. By attaching a dichroic mirror that transmits only infrared light to this halogen lamp, light relatively similar to solar radiation can be obtained in the visible light region. The case where a dichroic mirror is used is shown by a dotted line in FIG.

The light spectrum of a tungsten lamp is also continuous light as shown in FIG. 5, and is different from solar radiation in that it contains a large amount of infrared components. A metal halide lamp is one in which a metal gas such as mercury is enclosed in an arc tube, and the light spectrum thereof also includes the emission line spectrum peculiar to the enclosed metal element. Is different from.

As shown in FIG. 7, the spectrum of light obtained from a fluorescent lamp that is usually used in homes includes several emission line spectra, and does not include light at wavelengths longer than 700 nm. Not at all. The light spectrum of a xenon lamp, which is often used as the light source of a solar simulator, is relatively similar to solar radiation as shown in FIG. 8, but it has a bright line spectrum near 800 nm to 900 nm, Is different.

[0008] Generally, a commercially available solar simulator uses this xenon lamp as a light source and eliminates a bright line spectrum near 800 nm by a filter.
However, as shown in FIG. 9, the light from 800 nm to 900 nm is remarkably reduced by passing through the filter, so that the spectrum is different from that of solar radiation except in the visible light region.

[0009]

As described above, each light source has its own unique light spectrum, but the problem is that when these are used as the light source of a solar simulator, they can be used independently from ultraviolet irradiation to infrared irradiation. It is not possible to reproduce the solar radiation of. For example, a solar simulator that uses a xenon lamp as a light source, which has been mainly used up to now, is as described above from 800 nm to 900 nm.
, But the light near 800 nm is
A copper-indium-selenium solar cell that is located at the upper limit on the long-wavelength side of usable light of currently widely used amorphous silicon solar cells and that can use light of a longer wavelength than amorphous silicon solar cells. Also, light near 800 nm is used. For this reason,
It is clear that the performance of the solar cell is not fully exhibited when using the conventional solar simulator. In addition, this solar simulator is mainly used for the development of photothermal conversion devices such as water heaters that utilize the infrared light region, and for the cultivation of photosynthetic microorganisms such as photosynthetic bacteria that grow using near infrared light of 800 nm or more. not appropriate. On the other hand, a solar simulator using a metal halide as a light source is not suitable for measuring or evaluating color because it contains a large amount of bright line spectra in the visible light region.

As described above, since the conventional solar simulator can only be used for a specific purpose because only light in a certain wavelength range is similar to solar radiation, it has low versatility. It is a thing. The present invention has been made in view of the above points, and an object thereof is to provide a solar simulator capable of obtaining light having a spectrum similar to solar radiation from ultraviolet irradiation to infrared irradiation.

[0011]

In order to solve the above-mentioned problems, the solar simulator of the present invention comprises at least two types of light sources such as a xenon lamp and a halogen lamp, and light of different wavelength ranges from each of these light sources. At least one wavelength-dependent mirror such as a cold mirror or a sharp cut filter that selectively transmits and reflects light and extracts and mixes at least two types of transmitted light and reflected light.

[0012]

Since the solar simulator of the present invention is configured as described above, it makes maximum use of the light similar to the solar radiation of each light source, and uses the wavelength-dependent mirror to
It removes the bright line spectrum and extracts the light in the wavelength region that is insufficient with a single light source from other light sources, and sufficiently compensates for the drawbacks that cannot be avoided with a single light source.

[0013]

EXAMPLES As a result of studying various light sources, the present inventors have concluded that it is not possible to reproduce solar radiation from ultraviolet irradiation to infrared irradiation with only one type of light source. Therefore, as a result of intensive research on reproduction of solar radiation by two or more types of light sources, ultraviolet irradiation was performed by extracting and mixing lights of different wavelength ranges from at least two types of light sources using wavelength-dependent mirrors. It was possible to obtain a solar simulator similar to solar radiation from to infrared irradiation.

The present invention will be described below based on examples.
In carrying out the present invention, various light source combinations can be considered, but here, as an example, a solar simulator using a combination of a xenon lamp and a halogen lamp will be described. However, in this case, the halogen lamp is not equipped with a dichroic mirror. The xenon lamp has a color temperature of about 6000K, and the visible light region is similar to solar radiation as shown in FIG.
An emission line spectrum is included at ˜900 nm. Also,
Halogen lamps have a color temperature of around 3000 K, differ from solar radiation in that they have a small visible light component and a flat spectrum in the infrared light region, as shown in FIG. Therefore, by simply mixing these two light sources, it is not possible to eliminate the drawbacks such as the existence of the bright line spectrum and the lack of visible light components. Therefore, we decided to construct a solar simulator consisting of two types of light sources by introducing a mirror that has the function of selectively reflecting or transmitting wavelengths. Two examples will be specifically described below.

Embodiment 1 FIG. 1 is a schematic view showing the arrangement relationship of main constituent members of an embodiment of the solar simulator of the present invention. In FIG. 1, the traveling directions of the light from the light source and the light of the separated wavelengths are both indicated by arrows, and a spectrum diagram of light corresponding to each wavelength is additionally shown near the arrows. In FIG. 1, a xenon lamp 1 which is a light source is irradiated from the lower right, and a cold mirror 2 is used to transmit light in a wavelength range longer than 800 nm including an emission line spectrum and to irradiate ultraviolet light or visible light of 800 nm or less Reflect to surface 7. The halogen lamp 3, which is the other light source, illuminates from the upper left, and the sharp cut filter 5 transmits light in a wavelength range longer than 800 nm and reflects ultraviolet light and visible light of 800 nm or less. Light from the xenon lamp 1 having a wavelength shorter than 800 nm reflected by the cold mirror 2 and 80 from the halogen lamp 3 that has passed through the sharp cut filter 5
Light having a wavelength longer than 0 nm is mixed with each other to form light having a spectrum similar to that of solar radiation. Further, by passing this light through the aquarium 4, the infrared light can be removed and can be made more similar to the solar radiation reaching the surface of the earth. Further, in order to prevent the irradiation of the irradiation target 6 with the light of the wavelength not required by each light source, the light shielding plate 8 is provided between the two wavelength-dependent mirrors. FIG. 11 shows the spectrum of the light thus obtained, which is very similar to the solar radiation spectrum of air mass 1.5 in FIG. The object 6 is irradiated with this light. The wavelength selection characteristics of the cold mirror 2 and the sharp cut filter used at this time are shown in FIG. 2A is a diagram showing the relationship between the transmittance and the reflectance with respect to the wavelength of light for the cold mirror 2 and FIG. 2B for the sharp cut filter 5. The solid line indicates the transmittance and the dotted line indicates the reflection. It represents the rate.

Embodiment 2 FIG. 10 is a schematic view showing the arrangement relationship of main constituent members of another embodiment of the solar simulator of the present invention. In FIG. 10, the traveling directions of the light from the light source and the light of the separated wavelengths are both shown by arrows, and the spectrum diagram of the light corresponding to each wavelength is additionally shown near the arrows. In FIG. 10, the xenon lamp 1 which is the light source is illuminated from above, and the cold mirror 2 is used to transmit light in the wavelength range longer than 800 nm including the bright line spectrum.
It reflects ultraviolet light and visible light of 0 nm or less. The other light source, the halogen lamp 3, emits light from the side, and similarly, the cold mirror 2 transmits light in a wavelength range longer than 800 nm and reflects ultraviolet light and visible light of 800 nm or less.
The xenon lamp reflected by the cold mirror 2 is 1
Light with a wavelength shorter than 800 nm, and cold mirror 2
The light having a wavelength longer than 800 nm derived from the halogen lamp 3 that has passed through the light source is mixed with each other and becomes light having a spectrum similar to solar radiation. Further, by passing this light through the aquarium 4, the infrared light can be removed and can be made more similar to the solar radiation reaching the surface of the earth. The light thus obtained has the spectrum shown in FIG. 11 as in Example 1, and is very similar to the solar radiation spectrum of the air mass 1.5 in FIG. The object 6 is irradiated with this light.

As described above, the solar simulator of the present invention can obtain light having a spectrum very similar to solar radiation, but what is important in the second embodiment is two light sources,
The point is that the lights from the xenon lamp 1 and the halogen lamp 3 are extracted and mixed by using a single wavelength-dependent mirror.
Generally, a solar simulator needs to reproduce solar radiation with several kinds of light intensities according to the purpose of use. In Example 1, when the light intensity on the irradiation surface is changed by changing the distance from each wavelength-dependent mirror to the object to be irradiated, the lights from the two light sources are mixed on the irradiation surface. First, it is necessary to correct the angle of the light source and the wavelength dependent mirror.

On the other hand, in the second embodiment, since the lights from the two light sources are extracted and mixed by using one wavelength-dependent mirror, the distance from the wavelength-dependent mirror to the irradiation object is large. Even if the value is changed, the lights from the two light sources are always mixed on the irradiation surface, so that it is not necessary to correct the angles of the light source and the wavelength-dependent mirror. Further, it is possible to obtain the same performance as that of the first embodiment with a simpler structure.

In Examples 1 and 2, two types of light sources, a xenon lamp 1 and a halogen lamp 3, and a wavelength-dependent mirror such as a cold mirror 2 and a sharp cut filter 5 are used to selectively emit light from the light source. However, in addition to this, it is possible to apply the elimination of light in a specific wavelength range by an interference filter, the half of the light in a specific wavelength range by a half mirror, etc., depending on the case. Further, as a combination of light sources, it is effective to combine a halogen lamp with a dichroic mirror, a tungsten lamp, an ultraviolet fluorescent lamp, and the like. In the first and second embodiments, the wavelength selection characteristics of the xenon lamp 1, the halogen lamp 3, the cold mirror 2, and the sharp cut filter 5 are determined so that the spectrum is similar to the air mass 1.5. By adopting it, various solar radiations such as the air mass 1, the air mass 2, and the air mass 0 can be easily and accurately reproduced. This makes it possible to evaluate the characteristics and deterioration of substances outside the atmosphere in a room.

Since there are almost infinite combinations of wavelength-dependent mirrors such as selection of light source, cold mirror, sharp cut filter, half mirror, interference filter, etc., regardless of air mass, latitude / longitude, weather, season, etc. Any solar radiation spectrum can be reproduced with different light intensities. As described above, the solar simulator of the present invention is expected to be applied to a wide range of industrial fields and to have remarkable effects.

[0021]

The conventional solar simulator using one type of light source cannot reproduce all the solar radiation from ultraviolet radiation to infrared radiation, whereas the solar simulator of the present invention is described in the embodiment. Like, 2
By combining at least one kind of light source and at least one wavelength-dependent mirror, it has an excellent function of obtaining light that reproduces solar radiation from ultraviolet radiation to infrared radiation.

This solar simulator is not only optimal for the development and performance evaluation of various solar cells that use light of various wavelengths, but also for photothermal conversion devices such as water heaters that mainly use the infrared light region. It can also be used for development. In addition, when a plurality of devices are combined to convert light energy, it is possible to carry out this solar simulator alone.

Algae that grow mainly using visible light,
The solar simulator of the present invention is also effective for culturing photosynthetic microorganisms such as photosynthetic bacteria that grow using near infrared light of 00 nm or more. In recent years, attention has been paid to the production of useful substances such as hydrogen and pigments by photosynthetic microorganisms, which will greatly contribute to the progress of the field of photobioindustry. In addition, the solar simulator of the present invention can be used for color printing based on visible light in solar radiation, evaluation and inspection of fields dealing with colors such as painting, and monitoring of changes in physical properties caused by ultraviolet light during solar radiation. It can be used effectively.

As described above, the solar simulator of the present invention is useful in a wide range of industrial fields.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an arrangement of main constituent members of an embodiment of a solar simulator of the present invention.

FIG. 2 is a diagram showing wavelength selection characteristics of a cold mirror and a sharp cut filter used in the solar simulator of the present invention.

FIG. 3 Spectral diagram of solar radiation

FIG. 4 is a spectrum diagram of light obtained from a halogen lamp.

FIG. 5 is a spectrum diagram of light obtained from a tungsten lamp.

FIG. 6 is a spectrum diagram of light obtained from a metal halide lamp.

FIG. 7 is a spectrum diagram of light obtained from a fluorescent lamp.

FIG. 8 is a spectrum diagram of light obtained from a xenon lamp.

FIG. 9 is a spectrum diagram after the emission line spectrum of light obtained from a xenon lamp is deleted.

FIG. 10 is a schematic diagram showing the arrangement of main constituent members of another embodiment of the solar simulator of the present invention.

FIG. 11 is a spectrum diagram of light obtained from the solar simulator of the present invention.

[Explanation of symbols]

 1 Xenon lamp 2 Cold mirror 3 Halogen lamp 4 Water tank 5 Sharp cut filter 6 Radiant 7 Irradiated surface 8 Light shield

Front Page Continuation (72) Inventor Yasuo Asada 1-3 East Higashi Tsukuba, Ibaraki Industrial Technology Institute of Industrial Science and Technology (72) Inventor Eiju Nakada 2-8-11 Nishishinbashi, Minato-ku, Tokyo Foundation Law Institute of Global Environment and Industrial Technology CO2 stabilization project room (72) Satoshi Nishikata Satoshi Nishikata 2-8-11 Nishishimbashi, Minato-ku, Tokyo Foundation method

Claims (1)

[Claims] 1. At least two types of light sources, at least two types of transmitted light that selectively transmits and reflects light having different wavelength ranges from these light sources, and at least one wavelength dependency that extracts and mixes reflected light. A solar simulator characterized by being equipped with a mirror.