JP2021015017A - Band spectrophotometer - Google Patents

Abstract

To provide a spectrophotometer for improving accuracy of photon flux density measurement for each specific wavelength band.SOLUTION: In a spectrophotometer, a plurality of band pass photoelectric elements are embedded in a base part, and the photon flux density is measured while being divided into a predetermined wavelength band by each bandpass photoelectric element. The bandpass photoelectric element comprises a photoreaction element and an optical bandpass filter arbitrarily selected according to the wavelength band of light to be measured. The optical bandpass filter is installed on the photodetection surface side of the photoreaction element so that only the light transmitted through the optical bandpass filter is irradiated to the photoreaction element. The base part includes a plurality of buried regions that individually house individual bandpass photoelectric elements and have openings that allow illumination of the bandpass photoelectric elements. The buried regions are composed of an opaque material that surrounds all surfaces of the side and bottom portions of the bandpass photoelectric elements and opens a part or all of the top surface of the bandpass photoelectric elements.SELECTED DRAWING: Figure 1

Description

The present invention relates to a band spectrophotonometer, and is a device for measuring the photon flux density for each specific wavelength band contained in the light, particularly when it is irradiated with light having a wide wavelength such as sunlight or indoor illumination light. It is about.

Irradiation of light is important in the field of plant cultivation, but the wavelength (color) of the light emitted at that time may be focused on. That is, ultraviolet light (particularly A wave) has the effect of normalizing the shape of the plant, such as shortening the height of the plant, and thickening the leaves. Blue light is effective for photosynthesis, green light is effective for improving resistance to diseases, and red light is effective for photosynthesis and photosynthesis. Infrared light also has the effect of increasing the efficiency of photosynthesis. It has been reported that the growth of plants is promoted by controlling the wavelength of irradiation light by utilizing the effect of light in such a specific wavelength band. For example, there is a method of alternately irradiating red light and blue light (see Patent Document 1). In the case of such a cultivation method, an LED or the like that emits light in a desired wavelength band can be used, but in the case of cultivating by irradiating sunlight, the light in which wavelength band has a photon flux density of what degree. It was not easy to determine whether the light was irradiated with.

Further, in other fields, for example, the fluorescence spectrum may be measured in the detection of caries bacteria (see Patent Document 2). In order to detect such oral bacteria, it has been required to accurately disperse light in a specific wavelength band and measure the light intensity and amount.

JP-A-2015-204801 JP-A-2018-165708

Bilguun A., Nakaso T., Harigai T., Suda Y., Takikawa H., Tanoue H., “Development of simple band-spectral pyranometer and quantum meter using polypropylene cells and bandpass filters”, AIP Conference Proceedings, Vol.1709, , PP 020025_1-11 (2016)

As mentioned above, in the field of agriculture, although it is important to know the degree of photon flux density in a specific wavelength band to be irradiated, photons in a wide range of wavelengths are separated into specific wavelength bands. It was not easy to measure the bundle density. Therefore, the inventors of the present application have developed an apparatus capable of measuring the photon flux density while performing spectroscopy by a simple method (see Non-Patent Document 1).

In this device, a plurality of photoelectric cells are classified for each light in a specific wavelength band to be measured, and an optical bandpass filter is provided so that light in a wavelength band corresponding to each classification can be received. The final photon flux density was calculated by causing the photoelectric cell to receive only the light in a specific wavelength band of the irradiation light by the optical bandpass filter and measuring the intensity and amount by the photoelectric cell.

However, the light that reaches the photoelectric cell is not necessarily limited to the light that has passed through all of the optical bandpass filters, and the light that enters from the middle of the optical bandpass filter may also reach. This is because, for example, when the incident direction of the irradiation light is inclined, or when the light in the oblique direction is reflected by other members and incident, the optical bandpass filter depends on the angle of these incident directions. It was possible to reach the photoelectric cell without passing through. As a result, the incident of light that does not pass through the optical bandpass filter raises the value of the photoelectric cell in the specific wavelength band, so that there is a problem that accurate photon flux density cannot be measured.

The present invention has been made in view of the above points, and an object of the present invention is to provide a spectrophotonometer that improves the accuracy of photon flux density measurement for each specific wavelength band.

Therefore, the present invention is a spectrophotonometer in which a plurality of bandpass photoelectric elements are embedded in a base and the optical quantum flux density is measured while dividing into a predetermined wavelength band by each bandpass photoelectric element. Is provided with an optical reaction element and an optical bandpass filter arbitrarily selected according to the wavelength band of light to be measured, and the optical bandpass filter is such that only the light transmitted through the optical bandpass filter is the light. It is installed on the light receiving surface side of the photoreactive element so as to irradiate the reaction element, and the base portion includes a plurality of embedded regions individually accommodating individual bandpass photoelectric elements, and the embedded region is provided. Is characterized in that the entire bandpass photoelectric element is surrounded in a light-impermeable state except for an appropriate area on the uppermost surface of the bandpass photoelectric element.

According to the above configuration, first, since a plurality of bandpass photoelectric elements divided into a predetermined wavelength band are individually embedded in the buried region, among the light emitted to the buried region, It is possible to measure by each bandpass photoelectric element while separating a desired wavelength band from other wavelength bands. Secondly, since the embedded region has a configuration in which the entire bandpass photoelectric element is surrounded in a light-impermeable state except for a predetermined area on the uppermost surface of the bandpass photoelectric element, the case where the embedded region passes through the predetermined area portion. Except for the above, the intrusion of irradiation light into the inside of the buried member can be reduced to almost none. As a result, it is possible to avoid the occurrence of measurement value error due to the irradiation light not passing through the uppermost surface of the bandpass photoelectric element reaching the photoreactive element.

Here, in order to make the portion surrounded by the buried area light opaque, in addition to the case where the entire base is made of a light opaque material, the light transmittance to the buried area is reduced, the buried area is used. The inner surface of the light (for example, the bottom surface, the inner wall surface, etc.) may be subjected to an impermeable treatment. Further, the base may be made of a light-impermeable material, and then the inner surface of the buried region may be subjected to a light-impermeable treatment. In this case, basically, the transmission of light by the base material (light opaque material) is reduced, and the light transmission by the light opaque treatment is reduced as a secondary or preliminary, which is more preferable. You can get the situation.

Further, when the entire bandpass photoelectric element is surrounded in a light-impermeable state except for an appropriate area on the uppermost surface of the bandpass photoelectric element, the appropriate area is at least a part of the uppermost surface of the bandpass photoelectric element. However, it can be a circular or rectangular area. It is desirable that the appropriate area is provided near the center of the uppermost surface of the bandpass photoelectric element so that the light surely passes through the uppermost surface of the bandpass photoelectric element. The area at this time is arbitrary, and may be something like an extremely small pinhole.

The light-impermeable material is a material that reduces the light transmittance. For example, a white, colored or optically opaque synthetic resin or optically opaque ceramics or metal may be used. In order to reduce the transmission of light over the entire wavelength band to be measured, the coloring when it is colored can be done by absorbing light with a color that is black or close to black, or by making it white or infinitely white. This is due to the scattering of light by similar colors, but is not limited to these. It may be configured to be scattered or reflected by ceramics or metal, and a material having a function equivalent to these can be used. When a conductive material such as metal is used, it is necessary to perform an insulating treatment that should block the conductivity with the terminals and the like of the photoreactive element.

In addition, the light opaque treatment reduces the transmittance of the irradiated light, and absorbs the irradiation light by laminating a thin plate or thin film made of white, colored or optically opaque resin on the surface. It has one or more configurations selected from those that scatter and scatter the irradiation light by forming fine irregularities on the surface, or reflect by laminating or forming a film of a reflective material on the surface. is there. Therefore, for example, it can be assumed that a thin film of colored synthetic resin is laminated on the surface, and that light intrusion from the side portion can be reduced by reflecting the thin film. In addition, it may be scattered by forming fine irregularities on the surface by performing surface treatment such as shot blasting. In addition, "laminating" means adhering a specific material (either a single layer or a plurality of layers) formed in a film shape or a plate shape to the surface, and "forming a film" means, for example, It means forming a film on the surface by means of vapor deposition, plating, painting, or spraying paint.

Further, the optical bandpass filter in the above invention is selectively laminated on the optical reaction element according to the wavelength band of light to be measured, with different wavelength bands of each bandpass photoelectric element as a unit. Each photoreactive element may receive only the passing light of a specific wavelength band that has passed through the respective optical bandpass filter. Further, the wavelength band can be defined by dividing the wavelength in the range from ultraviolet light to infrared light into a plurality of bands. For example, five types of wavelength bands of 300 to 400 nm, 400 to 500 nm, 500 to 600 nm, 600 to 700 nm, and 700 to 800 nm can be set as specific wavelength bands. Further, six kinds of wavelength bands including a wavelength band of 800 to 900 nm may be set as a specific wavelength band, or all wavelength bands (that is, a band including all wavelengths from ultraviolet light to infrared light) may be included in one category. You may.

With such a configuration, it is possible to measure the photon flux density for light of a specific color. That is, when classifying in units of 100 nm as in the above example, when classifying wavelengths of 300 to 900 nm into 6 types for each 100 nm, ultraviolet light, blue light, green light, red light, far red light, and red Six types of external light can be classified and measured. Further, when the wavelengths of 300 nm to 800 nm are set to 5 types for each 100 nm and separately classified into one type of all wavelength bands, infrared light is obtained by obtaining the difference from the wavelength band at 300 to 800 nm. Instead, the remaining portion of the wavelength other than 300 to 800 nm can be calculated. In any aspect, such measurement of the photon flux density by each color light can be used to analyze the irradiation state in a specific wavelength range necessary for the growth of plants in a greenhouse.

In the invention of each of the above configurations, the embedded region has an opening corresponding to the appropriate area on the uppermost surface of the bandpass photoelectric element accommodated therein, and the bandpass photoelectric element is inside the embedded region. When housed in the bandpass photoelectric element, the uppermost surface of the bandpass photoelectric element reaches the opening of the embedded region, and at the opening of the embedded region, the peripheral edge of the opening and the uppermost surface of the bandpass photoelectric element A covering member that simultaneously covers a predetermined range including a peripheral edge may be provided.

In the case of the above configuration, the uppermost surface of the bandpass photoelectric element accommodated in the buried region reaches the opening of the buried region, and in this state, the peripheral edge of the opening and the outermost bandpass photoelectric element of the bandpass photoelectric element. Since the range including the peripheral edge of the upper surface is covered, it is possible to prevent light from entering the bandpass photoelectric element through the gap even when a gap is formed between the two peripheral edges. Further, even in a state where a step is formed due to a slight difference between the position of the uppermost surface of the bandpass photoelectric element and the position of the surface of the base portion, the peripheral edges of both can be covered with a covering member. The peripheral edge of either one is not exposed to the outside, and the cause of damage or the like can be eliminated in advance. The opening having the above configuration allows the irradiation light to pass through an appropriate area on the uppermost surface of the bandpass photoelectric element, and therefore limits the path of the passing light. Therefore, the opening area (that is, an appropriate area) in the opening may be a part of the uppermost surface of the bandpass photoelectric element, and the shape of the opening may be arbitrary and may be circular or rectangular. It should be noted that the opening area of the opening can also have the purpose and function of limiting the intensity and amount of light that can be received by the photoreactive element, and the size should be smaller than the light receiving surface of the photoelectric element to obtain the desired signal output size. It may be sized to obtain, or it may be something like an extremely small pinhole.

In the invention having the above configuration, the optical bandpass filter allows spacers made of an optically transparent material to be selectively laminated, and is used for each optical bandpass filter constituting each bandpass photoelectric element. The spacers selectively laminated in the above can be configured so that the uppermost surfaces of all the bandpass photoelectric elements reach the opening of the embedded region.

According to the above configuration, each bandpass photoelectric element has a different optical bandpass filter according to a desired specific wavelength band, but the overall wall thickness is increased due to the difference in the optical bandpass filter. Since there may be differences, the wall thickness of the entire bandpass photoelectric element can be made substantially uniform by laminating a spacer made of an optically transparent material on the optical bandpass filter. In this way, by making the wall thickness of the entire bandpass photoelectric element divided into a plurality of pieces uniform, the position of the photoreactive element even when the depths of the plurality of buried areas provided are all the same. And the position of the uppermost surface of the bandpass photoelectric element can be installed to the same extent.

Further, in each of the above-described inventions, a circuit for processing the measured value measured by the bandpass photoelectric element and a material arranged on an outer layer from the uppermost surface of the bandpass photoelectric element and attenuating the light transmission rate are used. It is provided with a configured dimming member, the light reflecting element is an element having a photoelectric conversion function, and the circuit is substantially short-circuited based on an electrical output value photoelectrically converted by the photoreactive element. The intensity / amount of light measured by the amount of change in the current value is converted into the photon flux density, and the dimming member converts the intensity / amount of light received by the photoreactive element according to the photoelectric conversion ability. It can be configured to adjust so that the correlation between the change in the light and the change in the substantially short-circuit current value is within the range showing linearity.

In the case of such a configuration, the electrical output is substantially the value of the short-circuit current, and the intensity and amount of light (photon flux density converted from this) can be obtained from the amount of change. The substantially short-circuit current means a current of the same degree as the current (short-circuit current) obtained by short-circuiting both electrodes of the photoreactive element. In addition to measuring with a current measuring device (ammeter), when outputting as a voltage value, connect resistors to both ends of the photoreactive element and significantly reduce the resistance value (combined resistance value). Therefore, a substantially short-circuit current value can be obtained from the voltage value based on Ohm's law. The value of this substantially short-circuit current can be regarded as the value of the short-circuit current of the photoreactive element. When reading by voltage, it is preferable to use a voltage amplifier, and when reading by current, it is preferable to use a current amplifier to convert the value into an easy-to-read value. Further, when these electrical values are used as outputs, the electrical signal can be passed through a noise filter.

In the case of the invention in which the intensity and amount of light are measured by the amount of change in the substantially short-circuit current value and converted into photon density as in the above configuration, the ND filter is arranged on the outer layer from the uppermost surface of the bandpass photoelectric element. Can be assumed to be. According to such a configuration, the amount of light emitted to the bandpass photoelectric element can be reduced (the irradiation light is dimmed). For this, the correlation between the change in the intensity and amount of solar radiation and the change in the substantially short-circuit current value when a small solar cell is used as the photoreactive element can be made linear (the relationship is directly proportional). That is, when measuring a change in a substantially short-circuit current value using a small solar cell, the linear correlation is broken in the range where the amount of solar radiation is reduced under the condition that the amount of solar radiation is excessive with respect to the small solar cell. However, under the condition that the amount of solar radiation is constantly reduced by dimming, a linear correlation appears.

In the above, in the case of the configuration in which the dimming member is provided on the outer layer from the uppermost surface of the bandpass photoelectric element, the light intensity is suitable for measuring the photon flux density by evenly attenuating the light over the entire band of the irradiation light. -The amount can be applied to the bandpass photoelectric element. As the dimming member at this time, a general commercially available ND (Neutral Density) filter can be used, and the same function as the ND filter (a function of evenly attenuating the light transmittance in the entire band). The material that exhibits the above can be replaced by a plate-shaped or sheet-shaped material. Examples of the material that exerts the above functions include ABS resin (acrylonitrile / butadiene / styrene copolymer synthetic resin), polypropylene, polystyrene, polyethylene, polytetrafluoroethylene, vinyl chloride, polyvinyl chloride, and the like in white, gray, or black. Some are colored. By forming these on a plate material or a sheet material, it can be used as a dimming member.

Further, in the case of the configuration in which the protective member is provided on the outermost layer, the protective member is provided on the uppermost surface of each bandpass photoelectric element, so that the protective member can be used outdoors. That is, even when it is installed at a high place outdoors, it is possible to eliminate the cause of damage due to a collision or the like of a branch of a tree soared by wind or the like. In this case, the protective member is composed of a single plate-shaped member and is installed on the uppermost surface of each bandpass photoelectric element under the same conditions so that the light receiving conditions in the photoreactive element are common. Can be done. Further, if the protective member is used as a lid for the buried member and has a peripheral portion thereof, it is possible to exert a function of preventing rainwater from entering and use it as a spectrophotonometer having waterproof performance. The protective member may be provided so as to form the uppermost surface of the bandpass photoelectric element, but may be provided on the outer layer of the uppermost surface of the bandpass photoelectric element. When it is installed on the outer layer of the uppermost surface of the bandpass photoelectric element, it may be laminated on the uppermost surface, or it may be installed in a separated state. In any case, the protective member is provided on the outermost layer (outermost layer), and in the case of the configuration in which the above-mentioned dimming member is provided on the outermost layer, it is provided on the outer layer rather than the dimming member. , The protective member and the dimming member may be integrated by laminating or the like. Further, when the protective member is made of a material that exhibits a dimming function (similar to the ND filter), the protective member may also serve as the dimming member.

In each of the inventions having the above configuration, the photoreactive element in the bandpass photoelectric element is any one of a solar cell, a photodiode, a phototransistor, a pyroelectric element, or a photoelectric cell, and is photoelectric in a wavelength band of 300 to 1000 nm. It can be configured by what causes the transformation. When such a photoreactive device is used, it is possible to electrically change the intensity and amount of light in a desired wavelength band, and the photon flux density is measured based on the converted electrical output. It becomes possible to (calculate).

Further, in the invention in the case where the photoreactive element is an element having a photoelectric conversion function, a circuit for processing the measured value measured by the bandpass photoelectric element is provided, and the circuit includes the short circuit described above. A device that converts the intensity and amount of light into photon flux density according to the amount of change in the current value, and is equipped with an amplifier circuit that amplifies the substantially short-circuit current value and a high-frequency noise filter that removes noise contained in the substantially short-circuit current. Can be.

In the case of the above configuration, since the short-circuit current value can be amplified while removing noise, even when the electrical output value due to the irradiation light is diminished, as in the case of dimming. It enables conversion to photon flux density.

Further, in the case where the band spectroscopic photonometer has a configuration in which an electrical output is obtained as described above and a configuration in which the photon flux density is measured by a change in a substantially short-circuit current value, these band spectroscopic photonometers are used as a unit. It is composed of a plurality of band spectrophotonometers having the same configuration, and a bypass diode is arranged in each bandpass photoelectric element, and in the same specific wavelength band. The bandpass photoelectric elements that measure the photon flux density can be configured to be electrically connected to each other.

According to the above configuration, since the plurality of bandpass photoelectric elements are connected to each other via a bypass diode, there is a case where the light irradiation is blocked by the influence of a shadow or the like on one of the bandpass photoelectric elements. However, it can be assumed that it does not affect the measurement of the photon flux density. That is, even when the output reduction occurs due to any of the bandpass photoelectric elements, the output reduction does not affect the value of the short-circuit current.

In the invention having the above configuration, the bottom surface of the embedded region is composed of a circuit board having a circuit for processing the measured value measured by the bandpass photoelectric element, and the circuit board constitutes the bottom surface. A light opaque state can be configured for the bottom of the bandpass photoelectric element.

In the case of the above configuration, the bottom portion constituting the buried region can be configured by a circuit board on which the bandpass photoelectric element is installed, and the installation of the circuit board can prevent the intrusion of light from the bottom portion.

Further, in the invention of each of the above configurations, the display unit for displaying the measured value, the transmitting unit for transmitting the measured value to the outside, and the measured value for the measured value in each wavelength band by the bandpass photoelectric element. It is possible to include at least one or more selected from the storage units that store the data as data, and a power source that supplies power to the one selected from these.

According to the above configuration, it is possible to display the measured value in real time or store it in a band spectrophotonometer, a host PC, or the like for management. In this case, in the form including the transmission unit, for example, the measured values measured by a plurality of band spectrophotometers installed in a greenhouse or outdoors can be centrally managed. That is, since the measured values installed at distant measurement points can be transmitted, the output values can be obtained without obtaining the measurement results at the measurement points, and the band spectrophotonometer is continuously connected to the measurement points. Only the measured value can be obtained while installing in. This makes it possible to manage changes in the photon flux density for each specific wavelength range at each point, even if the conditions of the irradiated sunlight differ due to changes in the weather conditions at each point. It can be used to predict the effect on the growing condition. As the storage unit, an internal storage device (HDD or the like) may be used, but a removable portable memory (SD card, USB memory or the like) may be used.

In the case of the invention having the above configuration, a calculation unit for calculating the photon flux density for each wavelength band based on the measured value is provided, and the power supply also supplies power to the calculation unit. The display unit, the transmission unit, or the storage unit may display, transmit, or store either or both of the measured value and the calculation result by the calculation unit.

According to such a configuration, since the photon density is calculated by the calculation unit, for example, when the photon density is obtained by the amount of change in the substantially short-circuit current value, the amount of change can be calculated, and the installation location. It is possible to correct the increase or decrease of the current value due to the temperature change of, and to amplify when the substantially short-circuit current value is very small. When it is necessary to temporarily store the measured value as data for the arithmetic processing in the arithmetic unit, the storage unit can be used, or a storage device or a buffer device different from this can be used. You may. Further, a solar cell can be used as the power source, and when a solar cell is used as the photoreactive element, the same type of solar cell may be installed for the power source.

According to the present invention, the bandpass photoelectric element surrounded by the embedded region receives the emitted light to prevent the intrusion of extra light other than the received light, and the irradiation light is separated into a plurality of wavelength bands. However, since the measurement by the photoreactive element is possible, the accuracy of the photon flux density measurement in those specific wavelength bands can be improved. In particular, since the bandpass photoelectric element is individually embedded in each of the plurality of configured embedded regions, it is possible to simultaneously measure the photon flux densities of light in a plurality of specific wavelength bands at the same point. Therefore, it is possible to measure the photon flux density of individual specific wavelength bands at the same time for changes in light intensity and quantity that change from moment to moment due to changes in weather conditions, such as sunlight irradiation, and plant growth. It can be used to predict the effect on etc.

It is explanatory drawing which shows the 1st Embodiment of this invention. (A) is a perspective view of the first embodiment, and (b) and (c) are cross-sectional views taken along the line IIB-IIB. It is explanatory drawing which shows the 2nd Embodiment of this invention. It is explanatory drawing which shows the 3rd Embodiment of this invention. (A) is a cross-sectional view of the third embodiment, and (b) and (c) are cross-sectional views showing a modified example. It is explanatory drawing which shows the modification of the 3rd Embodiment. It is explanatory drawing which shows the other embodiment of this invention. It is explanatory drawing which shows the other embodiment of this invention. It is explanatory drawing which shows the whole structure in another embodiment. It is explanatory drawing which shows the detection circuit example of the measured value. It is a graph which shows the result of the preliminary experiment. It is a graph which shows the result of Experiment 1. It is a graph which shows the result of Experiment 2.

<First Embodiment>
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a first embodiment of the present invention. As shown in this figure, the spectrophotonometer A of the first embodiment has a base 1 and a bandpass photoelectric element group 2 (a plurality of bandpass photoelectric elements CH0, CH1, CH2, CH3, CH3) embedded therein. CH4, CH5, hereinafter, these may be collectively referred to as a bandpass photoelectric element group), and a protective member 3 disposed on an upper layer. The base 1 is made of an opaque material, and is provided with a plurality of embedding regions 10, 11, 12, 13, 14, 15 that allow embedding of individual bandpass photoelectric elements CH0 to CH5.

One bandpass photoelectric element can be embedded in each of the buried areas 10 to 15. Further, the buried regions 10 to 15 are configured to have a predetermined depth from the surface of the base portion 1 and have a structure of opening (having an opening) on the surface of the base portion 1. The individual depths of the buried regions 10 to 15 are appropriately adjusted according to the height of the bandpass photoelectric elements CH0 to CH5 to be embedded, and the uppermost surface of the individual bandpass photoelectric elements CH0 to CH5 is the surface of the base 1. Is configured to reach. Since optical bandpass filters (described later) for selectively receiving light in a desired band are laminated on the individual bandpass photoelectric elements CH0 to CH5, the heights are imbalanced with each other. The depth is adjusted to.

The five bandpass photoelectric elements CH1 to CH5 in the bandpass photoelectric element group 2 are for measuring the intensity and amount of light (photon flux density) in a specific wavelength range, and have different wavelengths. The spectroscopic function can be obtained by enabling the measurement of the region. Further, in the present embodiment, the remaining one CH0 is a reference photoelectric element without an optical bandpass filter (however, in the following, the reference photoelectric element CH0 may be included and referred to as a bandpass photoelectric element). Then, all of these bandpass photoelectric elements CH1 to CH5 and the reference photoelectric element CH0 are embedded side by side in the base 1, so that the photon flux density can be measured in a state of being separated with respect to the light of the same light source. It has become.

Since the buried regions 10 to 15 are provided at an appropriate depth as described above, the bandpass photoelectric elements CH0 to CH5 can be formed by burying the bandpass photoelectric elements CH0 to CH5 in the buried regions 10 to 15. The side portion and the bottom portion are buried in the base portion 1. That is, only the uppermost surfaces of these bandpass photoelectric elements CH0 to CH5 are exposed on the surface of the base 1. Since the entire base 1 is made of a light-impermeable material, the light emitted to the bandpass photoelectric elements CH0 to CH5 is limited to the one transmitted only on the uppermost surface.

By the way, as the light-impermeable material, a colored synthetic resin can be used, and a colored synthetic resin can be formed by adding a pigment or a dye to a polymer. Examples of the polymer include acrylic-based polymers, olefin-based polymers, vinyl-based polymers, cellulose-based polymers, amide-based polymers, urethane-based polymers, fluorine-based polymers, silicone-based polymers, and imide-based polymers. Among these, for example, triacetyl cellulose (TAC), polyethylene terephthalate (PET) and the like can be used. In addition, as the colored synthetic resin, general-purpose resins used in 3D printers such as so-called engineering plastics, nylon, ABS resin, and PLA resin can also be used. Coloring is by adding pigments or dyes to these resins, but as pigments or dyes, it is possible to select white or a color close to white, or black or a color close to black. it can.

Since the base portion 1 has the above-described configuration, the side portions and the bottom portions of the bandpass photoelectric elements CH0 to CH5 come into contact with (or adhere to) the surfaces of the buried regions 10 to 15, respectively, so that the base portion 1 blocks light. Is to be done. With such a configuration, each bandpass photoelectric element CH0 to CH5 has a region that allows light to be transmitted only on the uppermost surface.

Therefore, in each of the bandpass photoelectric elements CH0 to CH5 in the embedded state, light is allowed to enter only from the uppermost surface, and light cannot reach the side surface portion or the bottom surface portion from the outside. It is. Then, photoreactive elements 20a, 21a, 22a, 23a, 24a, 25a are provided on the lowermost layer of each of the bandpass photoelectric elements CH0 to CH5, and react to the light incident from the uppermost surface of the bandpass photoelectric elements CH0 to CH5. It has become possible.

Further, since the individual bandpass photoelectric elements CH1 to CH5 excluding the reference photoelectric element CH0 receive only light in a desired wavelength range by the optical reaction elements 21a to 25a, the light reaction elements 21a to 25a are received from the uppermost surface. Optical bandpass filters 21b, 22b, 23b, 24b, and 25b are provided between them. In these bandpass photoelectric elements CH1 to CH5, optical bandpass filters 21b to 25b arbitrarily selected according to the wavelength range of light to be measured are laminated on the surface of the optical reaction elements 21a to 25a. For example, when the first bandpass photoelectric element CH1 measures light in the wavelength range of 300 to 400 nm, and then the fifth bandpass photoelectric element CH5 is measured stepwise for each 100 nm wavelength range. An optical bandpass filter corresponding to these wavelength ranges will be selected. The optical bandpass filters 21b to 25b are all composed of a combination of a high-pass filter and a low-pass filter. The high-pass filter blocks light in the wavelength band below the lower limit, and the low-pass filter blocks light in the wavelength band above the upper limit. It is a thing. The high-pass filter and the low-pass filter may be composed of one layer or a laminated body of a plurality of filters. In any of the configurations, the irradiation light is dispersed as a whole by allowing the light in a desired wavelength range to pass in a stepwise manner.

The photoreactive elements 20a to 25a used in all the bandpass photoelectric elements CH0 to CH5 have the same performance. This is because when all the bandpass photoelectric elements CH0 to CH5 are simultaneously irradiated with the same light, in the measurement of each light received (spectroscopically) individually for each specific wavelength region, the individual photoreactive elements 20a to This is because the performance of 25a does not cause a difference. Examples of the photoreactive elements 20a to 25a include solar cells, photodiodes, phototransistors, pyroelectric elements, photoelectric cells and the like. Of these, solar cells can be preferably used. By using the electric power generated by the irradiation of light, an external power source can be eliminated. In addition, the intensity and amount of light can be measured according to the power generation state of the solar cell, and this can be converted into the photon flux density.

Further, the spectrophotonometer A of the present embodiment has a configuration in which the protective member 3 is arranged on the uppermost surface of the bandpass photoelectric elements CH0 to CH5. The protective member 3 is made of a light-transmitting material, and can be made of resin, glass, ceramics, or the like. When a resin is used, a fluororesin (PTFE, PFA, FEP, ETFE, etc.) can be used, and when glass is used, an optically transparent tempered glass is used. In the figure, the protective member 3 is provided in a state of being in contact with the uppermost surfaces of the bandpass photoelectric elements CH0 to CH5, but it is not necessary for the two to be in contact with each other, and the protective member 3 may be arranged in a state of being separated from each other.

As shown in the figure, the protective member 3 can be uniformly protected by a single plate-like body, or may be individually provided on the uppermost surfaces of the individual bandpass photoelectric elements CH0 to CH5. Good. When protected by an individual protective member, the protective member can be configured as a part of the bandpass photoelectric elements CH0 to CH5.

By the way, in the spectrophotonometer A of the present embodiment shown in FIG. 1, a bandpass photoelectric element (reference photoelectric element) CH0 having no optical bandpass filter is provided. As described above, in the bandpass photoelectric element CH0, an optical bandpass filter is arbitrarily selected according to the wavelength range and laminated on the photoreaction element 20a, but here, the wavelength range of light to be measured is set. Is set to the entire wavelength range, and in order to comply with the wavelength range, it is selected not to use the optical bandpass filter. In reality, in the case of a configuration not provided with an optical bandpass filter, the bandpass photoelectric element is different from the bandpass photoelectric element, but the bandpass photoelectric element is similarly provided as an optional option. It is supposed to be called.

Since such a reference photoelectric element CH0 can measure the entire wavelength range of the irradiation light, by providing the reference photoelectric element CH0, the measured values at individual specific wavelengths and all wavelengths can be measured. It is possible to calculate the irradiation state (photon flux density) of light in the wavelength range outside the measurement by the difference of the measured values in the region. When the reference photoelectric element CH0 is embedded in the base 1, an embedded region 10 for the reference photoelectric element CH0 is provided in advance in the base 1. In this case, the buried area 10 is also configured so that the range other than the uppermost surface is surrounded by the light-impermeable material.

Instead of the above-mentioned photoelectric element CH0 for all wavelength ranges, a bandpass photoelectric element (sixth bandpass photoelectric element) CH6 for measuring another wavelength range may be used. In this case, the light in the wavelength range of every 100 nm can be measured in 6 steps from CH to CH5. For example, in CH1 to CH5, the wavelength range from 300 to 800 nm can be divided into wavelength ranges of 100 nm, and the wavelength range from 800 nm to 900 nm can be further functioned as the sixth bandpass photoelectric element CH6.

Since the present embodiment has the above configuration, the bandpass photoelectric elements CH0 to CH5 are embedded in the buried regions 10 to 15 of the base 1, and the protective member 3 is further placed on the upper surface of the base 1 (bandpass photoelectric elements CH0 to CH5). By installing it on the uppermost surface of the above, the whole can be integrated as shown in FIG. 2A.

In the present embodiment, since the protective member 3 is composed of a single plate-like body, as shown in FIG. 2A, the entire upper surface of the base 1 is integrally shielded by the protective member 3. It is supposed to be transformed. Even in a state where the upper surface of the base portion 1 is shielded by the protective member 3, since the protective member 3 is made of a light-transmitting material, it is embedded in the base portion 1 (buried areas 10 to 15). Irradiation light can reach the bandpass photoelectric elements CH0 to CH5.

By the way, the base 1 can be configured as one mass as a whole as shown in FIG. 2 (b), but even if it is configured as a hollow body as shown in FIG. 2 (c). Good. In the case of the spectrophotonometer B having a hollow inside, it is possible to incorporate various devices such as a circuit board for processing the measured values by the bandpass photoelectric elements CH0 to CH5 inside the hollow. It becomes. Further, when the spectrophotonometer B is composed of such a hollow base portion 1, a part of the base portion 1 (for example, a bottom surface portion) is configured to be detachable from another portion (for example, a side surface portion). You may. Since a part of the circuit board is removable, it may be easy to install / remove the circuit board or the like to be built in the hollow.

<Second embodiment>
The second embodiment is shown in FIGS. 3 (a) and 3 (b). Note that FIG. 3A illustrates a spectrophotonometer C showing the basic configuration of the second embodiment, and FIG. 3B illustrates a spectrophotonometer D showing a modified example thereof. .. The second embodiment is a modification of the first embodiment with respect to the configuration of the base 1. That is, as shown in FIG. 3A, the base 101 of the second embodiment has concave embedded regions 110, 111, 112, 113 for embedding the bandpass photoelectric elements CH0 to CH5. 114 and 115 are formed, and the bottom surface portion and the side wall portion thereof are subjected to light opaque treatment. The bottom surface portion and the side wall portion of each of the buried regions 110 to 115 can be brought into contact with the side portions and bottom portions (all surface portions except the uppermost surface) of the bandpass photoelectric elements CH0 to CH5.

The opaque treatment in this case is to reduce the transmittance of the irradiated light, for example, to color the surfaces of the bottom surface portion and the side wall portion of the buried area 110 to 115 with a paint having a predetermined color. In addition to this, light may be scattered by forming fine irregularities on the surface by performing surface treatment such as shot blasting to reduce the transmittance. Coloring with paint can be done by spraying as well as by coating. Further, a thin plate or a thin film may be laminated on the surface to reduce the light transmittance. As the thin plate or the thin film, a resin colored in white or colored can be used, and also optically. Those composed of opaque resin can be used. In short, it is configured to absorb or scatter the irradiation light by laminating a thin plate or a thin film on the surface. In the case of laminating thin films, a reflective material may be formed on the surface.

Further, by depositing or plating a reflective material (for example, a metal material such as nickel or chromium) on the surface as an opaque treatment, a reflective material is formed (or formed) on the surface of the buried regions 110 to 115. Some have a laminated structure. By forming (or laminating) a material capable of reflecting light on the surface of the buried areas 110 to 115 in this way, light incident from the outside of the buried areas 110 to 115 is shielded by reflection, and an opening is also formed. The light to be measured incident from the portion can be kept inside the buried areas 110 to 115. Since the material having such reflectivity (metal material) has conductivity, at least in order to prevent conduction with the terminals of the photoreactive elements 20a to 25a constituting the bandpass photoelectric elements CH0 to CH5, at least. Insulation treatment (arrangement of an insulating sheet or the like) is applied to a portion (for example, a part or all of the bottom surface portion) where the terminals abut.

As an example of the above modification, as shown in FIG. 3B, the base 201 has the buried areas 210a, 211a, 212a, 213a, 214a, and 215a formed in a concave shape, and the buried areas 210a to 215a have a box shape. An example will be illustrated in which the buried area covering portions 210b, 211b, 212b, 213b, 214b, and 215b configured in the above are accommodated. The buried area covering portions 210b to 215b are formed in advance in a box shape by a light-impermeable material. Further, this box-shaped shape is provided so that the outer periphery is in contact with or in close contact with the buried regions 210a to 215a, and the inner periphery thereof can be in contact with or in close contact with the surfaces of the bandpass photoelectric elements CH0 to CH5. It has become.

Therefore, the buried area covering portions 210b to 215b are housed in the buried area 210a to 215a, and by integrating these, the buried area covering portions 210b to 215b are subjected to a light opaque treatment on the surface of the buried area 210a to 215a. It can be regarded as a state. That is, since the buried area covering portions 210b to 215b are composed of the colored resin, the bottom surface portion and the side wall portion of the buried area 210a to 215a are covered with the resin, and the inside of the buried area 210a to 215a is covered. On the other hand, the buried region covering portions 210b to 215b reduce the light transmittance.

The bandpass photoelectric elements CH0 to CH5 are embedded at predetermined positions of the bases 101 and 201 configured by the above configuration, and the spectrophotonometer D is configured as a whole. Further, by disposing or laminating the protective members 103 and 203 on the uppermost surfaces of the bandpass photoelectric elements CH0 to CH5, the bandpass photoelectric elements CH0 to CH5 can be protected.

With the above configuration, in the spectrophotonometers C and D in any form, the bases 101 and 201 themselves do not need to be composed of a light-impermeable material, and can be formed of any material. As a whole, at least the surfaces of the buried regions 210a to 215a are subjected to the light opaque treatment (or have the same configuration as the light opaque treatment), so that the bases 101 and 201 are tentatively illuminated. Is reduced, but the light transmitted through the buried areas 110 to 115, 210a to 215a (or the buried area covering portions 210b to 215b) is reduced, so that the light is transmitted exclusively from the uppermost surfaces of the bandpass photoelectric elements CH0 to CH5. The incident light can reach the photoreactive element.

<Third embodiment>
FIG. 4 shows a third embodiment. The spectrophotonometer E of this embodiment has substantially the same form as that of the first embodiment (spectrophotonmeter A), but on the surface of the base 1 (the surface on which openings are formed in the buried regions 10 to 15). The configuration differs in that the covering members 4 are laminated. That is, the covering member 4 is formed in a sheet shape or a plate shape by a light-impermeable material, and the region covered by the covering member 4 is assumed to have the light transmittance reduced. Then, as shown in FIG. 4, the covering member 4 is provided with communication portions 40, 41, 42, 43, 44, 45 having an opening of a region smaller than the opening of the buried regions 10 to 15. Therefore, light can be transmitted only in the communication portions 40 to 45.

In the present embodiment, the covering member 4 covers the entire surface of the base portion 1, and the communicating portions 40 to 45 are arranged according to the positions of the openings of the buried areas 10 to 15. Moreover, since the area is smaller than the openings of the buried areas 10 to 15, the peripheral edges of the openings of the buried areas 10 to 15 are included, and a predetermined range inside the peripheral edges of the openings is covered. 40 to 45 can transmit light only in an appropriate range including the central portion of the uppermost surface of the bandpass photoelectric elements CH0 to CH5 embedded in the buried regions 10 to 15.

The covering member 4 of the present embodiment is made of a flexible elastic material such as rubber, and the back surface side of each of the communication portions 40 to 45 is brought into contact with the uppermost surfaces of the bandpass photoelectric elements CH0 to CH5. By compressing the covering member 4, the covering member 4 is deformed into an appropriate shape (a state in which they are in close contact with each other). The communication portions 40 to 45 mean a state in which they are optically opened and communicate with each other, and are not only in a physically open state but also depending on a material capable of transmitting light. Although it includes a shielded state, here, a physically opened state is typically illustrated.

Since the configuration is as described above, when the surface of the base portion 1 is covered with the covering member 4, as shown in FIG. 5A, each of the covering members 4 is formed in the openings of the buried areas 10 to 15. Limited light transmission by the communicating portions 40 to 45 is allowed, and the photon flux density is measured for the incident of light within the range (corresponding to the area) of the openings 40 to 45. In the figure, the peripheral edges of the communicating portions 40 to 45 of the covering member 4 are shown in a state of being deformed by compression at the time of contact with the uppermost surfaces of the bandpass photoelectric elements CH0 to CH5.

At this time, the uppermost surfaces of the bandpass photoelectric elements CH0 to CH5 are in a state of reaching the openings of the buried regions 10 to 15, and are in a state of slightly protruding outward (upward) from the openings. As a result, the covering member 4 exerts an optical sealing effect. That is, a slight gap is formed between the peripheral components of the buried regions 10 to 15 (particularly, the peripheral edge of the opening) and the side portions (particularly, the peripheral edge of the uppermost surface) of the bandpass photoelectric elements CH0 to CH5. In this case, it is possible to prevent light from entering through the gap and reaching the photoreactive element. When the covering member 4 is made of a easily deformable material such as a rubber material, the sealing effect is improved by the pressing by the protective member 3.

Incidentally, a gap between the two may be generated due to a manufacturing error between the individually manufactured base 1 and the bandpass photoelectric elements CH0 to CH5. Further, in the case where the bandpass photoelectric elements CH0 to CH5 are loosely fitted to the buried regions 10 to 15 in order to make the structure easy to manufacture, the generation of a gap is unavoidable.

In the third embodiment of the above configuration, the protective member 3 is laminated on the upper surface side of the covering member 4, but the uppermost surfaces of the bandpass photoelectric elements CH0 to CH5 can be configured by the protective member. In this case, the ND filter may be installed instead of the protective member 3.

In the present embodiment, in order to simplify the structure of the buried regions 10 to 15, the depth dimensions of the buried regions 10 to 15 are substantially uniform, for example, as in the spectrophotonometer F shown in FIG. 5 (b). It may be configured in a state. In this case, the heights of the bandpass photoelectric elements CH0 to CH5 are set to be substantially the same in order to correspond to the depths of the buried regions 10 to 15. In order to adjust the height of the bandpass photoelectric elements CH0 to CH5, for example, a spacer (optically transparent material) 20c, which has an appropriate wall thickness, is formed on all or a part of the bandpass photoelectric elements CH0 to CH5. The 21c, 22c, 23c, and 24c can be selectively laminated on the photoreactive element 20a or the optical bandpass filters 21b to 24b.

As the selective stacking at this time, for example, assuming that the fifth bandpass photoelectric element CH5 is the highest, the height is adjusted to match the height of the fifth bandpass photoelectric element CH5. Means to adjust. That is, other bandpass photoelectric elements CH0 to CH4 other than the highest bandpass photoelectric element CH5 are selected, and those having the optimum thickness as the respective spacers 20c to 24c are selected. As a selection at this time, in a state where the bandpass photoelectric elements CH0 to CH5 after height adjustment are loosely fitted in the buried regions 10 to 15, the uppermost surface of the bandpass photoelectric elements CH0 to CH5 is eventually selected. Is also allowed to reach above (at least to the surface) the surface of the base 1. This is to enable coating by the covering member 4 provided on the upper layer. Further, by reaching above the surface and slightly projecting from the surface of the base 1, the optical sealing effect of the covering member 4 can be sufficiently exhibited.

In the above-described embodiment, the base 1 may be entirely made of a light-impermeable material, or the surfaces of the buried regions 10 to 15 may be light-impermeable. At this time, for example, when processing by vapor deposition or plating of a reflective material (for example, a metal material), the bottom of the buried regions 10 to 15 is formed as in the spectrophotonometer G shown in FIG. 5 (c). Is insulated. As the insulation treatment, for example, as shown in the drawing, the insulating sheets 10a, 11a, 12a, 13a, 14a, 15a formed in advance by the insulating material may be provided. This is to ensure insulation with respect to the terminals of the photoreactive elements 20a to 25a. Then, if the insulating sheets 10a to 15a are made of a easily deformable material such as a rubber material as in the case of the covering member 4, the insulating sheets 10a to 15a and the covering member 4 are mutually deformed. As a result, a stable buried state can be obtained between the base 1 (bottom of the buried areas 10 to 15) and the protective member (or ND filter) 3. The insulation treatment is not limited to the form of an insulating sheet, as long as the insulating property is ensured.

<Modified example of the third embodiment>
The third embodiment can be modified as shown in FIG. In this modification, the communication portions 40 to 45 to be opened in the covering member 4 are circular, and the opening area is smaller than that of the rectangular communication portion in the third embodiment. .. The area of the communication portions 40 to 45 may be any size as long as it opens a part of the uppermost surfaces of the bandpass photoelectric elements CH0 to CH5. Furthermore, when the opening area is set to be extremely small (for example, the size is set to a pinhole), the bandpass is in a state where the intensity and amount of light are reduced in advance without reducing the transmitted light of the ND filter or the like. It is also possible to irradiate the photoelectric elements CH0 to CH5.

<Other Embodiments>
7 and 8 show other embodiments. In the spectrophotonometer H of the embodiment shown in FIG. 7, the base portion 1a and the side wall 1b thereof are divided. This is a configuration in which the bandpass photoelectric elements CH0 to CH5 can be inserted from the side. That is, the bandpass photoelectric elements CH0 to CH5 are not limited to the case where they are installed from above with respect to the base 1 as in the first to third embodiments, but are installed in the base 1a from the side. It may be a thing.

In this case, the side wall of the base portion 1a is provided with a horizontal hole through which the bandpass photoelectric elements CH0 to CH5 can be inserted, and the side hole is closed by the side wall 1b. Further, the upper surface side of the base portion 1a is integrally formed with a top portion provided with communication portions 40 to 45 in advance, and the covering member 4 as described above may not be provided.

Further, in the spectrophotonometer I of the present embodiment shown in FIG. 8, the bottom of the buried region is composed of the circuit board 5. Here, the buried area constituent portions 10b, 11b, 12b, 13b, 14b, 15b to be formed in the base portion 1 are simply formed by through holes formed in a tubular shape. By installing the base 1 on the surface of the circuit board 5, the tubular buried area constituents 10b to 15b and the circuit board 5 form a bottomed tubular buried area as a whole.

The photoreactive elements 20a to 25a can be mounted on the circuit board 5, and the optical bandpass filters 21b to 25b and the spacers 20c to 24c are laminated on the photoreactive elements 20a to 25a as a whole. The bandpass photoelectric elements CH0 to CH5 described above are configured. FIG. 8 shows a state in which only the photoreactive elements 20a to 25a are mounted on the circuit board 5, but in reality, the circuit board 5 is in a state where the above-mentioned bandpass photoelectric elements CH0 to CH5 are integrated. It is implemented in.

In this way, the bandpass photoelectric elements CH0 to CH5 mounted on the circuit board 5 are inserted into the buried area constituents 10b to 15b of the base 1, so that the bandpass photoelectric elements CH0 to CH5 have an embedded region configuration. It will be surrounded by the parts 10b to 15b and the circuit board 5, and the light transmitted through the surfaces (sides and bottoms) other than the uppermost surface of the bandpass photoelectric elements CH0 to CH5 can be diminished.

Further, circuit elements (for example, operational amplifier 51, CPU 52, etc.) necessary for measuring the photon flux density can be mounted on the circuit board 5, and a power supply or the like is connected together with a storage device such as a logger or a communication device. be able to. If a solar cell is used as a power source, it is possible to operate these devices at least in a state where the photon flux density of the irradiation light should be measured (environment in which the light is irradiated).

Further, in the present embodiment, the circuit board 5 is housed in a box-shaped case 50a, and the case 50a is configured as a container having a predetermined capacity together with the lid portion 50b. The case 50a may be made of a light-impermeable material, but since it includes the base 1 as described above, it may be provided of a material capable of transmitting light. On the other hand, the lid portion 50b has a top plate portion 53 and a peripheral portion 54. In order to function as the protective member 3, the top plate portion 53 may be formed of an optically transparent material or may be formed as an ND filter by using a material that attenuates the light transmittance. A window 55 for providing the protective member 3 or the ND filter may be formed on the top plate portion 53. In any case, the covering member 4 installed on the surface of the base 1 can be pressed, and by pressing the covering member 4, the individual bandpass photoelectric elements CH0 to CH5 are optically pressed. It exerts a good sealing effect.

Further, since the peripheral portion 54 constitutes the lid portion 50b together with the top plate portion 53, the upper surface and the side surface of the case 50a can be covered by attaching the lid portion 50b to the case 50a, and the peripheral portion 54 is housed inside the case 50a. It is possible to protect each device to be installed. When the top plate portion 53 is used as the protective member 3, it can protect against falling objects and the like outdoors, and by covering the side surfaces at the same time, the waterproof effect is improved and rainwater and the like are prevented from entering. It is also possible to do. By providing the display screen 56 on the top plate portion 53, it is possible to display the power supply state, the measurement state, and other operating states.

Here, FIG. 9 shows the overall configuration when the circuit board 5 as described above is used. As shown in this figure, the overall configuration is composed of the spectrophotonometer I, the processing device 6, the power supply device 7, and the external devices 8a and 8b configured as described above. The detailed configuration of the spectrophotonometer I is as described above, and includes a plurality of bandpass photoelectric elements CH0 to CH5, and the intensity and amount of light measured by the bandpass photoelectric elements CH0 to CH5 (particularly photoreactive elements). Is output to the processing device 6, and the processing device 6 converts it into a photon flux density.

The processing device 6 is provided with a timer 61 to record the measurement time together with the measurement result, and is provided with the temperature sensor 62 to measure the temperature at the measurement point (particularly around the photochemical element). It is possible to correct the output error of the photoreactive element due to the temperature change. Further, the processing device 6 is provided with an amplifier circuit (op amp) 63 (51 in FIG. 8). This assumes the case of using a small solar cell as a photoreactive element, and in order to make a linear correlation between the change in light intensity / amount and the change in output (approximately short-circuit current value) appear. The output is amplified by reducing the irradiation amount by dimming. Further, a data logger 64 is provided to record the data to be output.

The processing device 6 is provided with a storage device 65 of an internal storage device (HDD or the like) or a portable memory (SD card or the like) that can be taken out, and stores the measurement results as data and also stores the calculation results by the calculation means described later. be able to. Further, the processing device 6 is provided with a CPU 66 (52 in FIG. 8) as a calculation means, and is converted into a photon flux density based on an output value (amount of power generated by a solar cell) measured by a photoreactive element. This is converted into output data (output signal). The data converted into the output signal is output to the transmission unit 8a installed as an external device via the output interface 67, and can be transmitted from the transmission unit 8a to a remote location. In principle, the transmission unit 8a is a wireless transmission device, but it may be a wired transmission device. Further, in addition to the transmission unit 8a, the data converted may be displayed on the display unit 8b installed as an external device.

It should be noted that each of the above devices is not essential and may be selectively installed and connected. For example, the measurement result may be transmitted without providing a CPU, or may be stored in the storage device 65 without transmission. Further, the transmission unit 8a and the display unit 8b may be provided with both, but only one of them may be provided. Further, since a power source is required to operate the processing device 6 and the external devices 8a and 8b, the power source device 7 is provided with a solar cell. The power supply device (solar cell) 7 is different from the photoreactive element in that it has a sufficient amount of power generation. When the power supply device 7 is a solar cell, light irradiation is required to supply power, but measurement of the photon flux density by a spectrophotonometer is basically required when the power supply device 7 is irradiated with light. Since it is a thing, there is no problem as long as the power can be supplied at least when there is irradiation of light to be measured. The power supply device 7 is not limited to the solar cell, and other power supply devices may be used.

Here, FIG. 10A shows a measurement value detection circuit when a small solar cell is used as the photoreactive element. The photoreactive elements (solar cells) 20a to 25a constituting the bandpass photoelectric element group 2 generate electricity by receiving light and output electric power. The intensity and amount of the received light are obtained by measuring the substantially short-circuit current value using the generated power. Specifically, for solar cells (each of the photoreactive elements 20a to 25a), a resistor 9 is connected between the two electrodes. When the resistance value of the resistor 9 is extremely small, the current value between the two poles X and Y can be measured as a substantially short-circuit current value (current value extremely close to the short-circuit current). The substantially short-circuit current value can be calculated based on Ohm's law for the voltage generated between the two poles X and Y. Although the bandpass photoelectric element group 2 is shown as one configuration in the figure, a substantially short-circuit current value is individually output for each of the individual bandpass photoelectric elements by the same configuration.

Further, as described above, when the irradiation light is attenuated by an ND filter or the like in order to make a linear correlation between the change in light intensity / amount and the change in output (substantially short-circuit current value) appear, the sun Since the output value (substantially short-circuit current value) of the batteries (photoreactive elements 20a to 25a) is small, it may be configured to amplify this. FIG. 10B is an example of a circuit configuration when an amplifier circuit (op amp) 90 is used. As shown in this figure, a resistor 9 is connected in series to a solar cell (photoreactive elements 20a to 25a), and then an operational amplifier 90 is further connected to amplify a substantially short-circuit current value. When noise is included in the substantially short-circuit current, the noise portion is also amplified by the amplifier circuit 90. Therefore, in the present embodiment, a capacitor connected in parallel with the amplifier circuit 90 is provided as a high-frequency noise filter.

Further, when a solar cell is used as the photoreactive elements 20a to 25a, as shown in FIG. 10 (c), bypass diodes are used for each of a plurality of (two in the figure) photoreactive elements 20a to 25a of the same type. After connecting 91 and 92 in parallel, they can be connected in series or in parallel (the figures are connected in series) so as to obtain a substantially short-circuit current between the two poles X and Y. Since the bypass diodes 91 and 92 are connected to the individual photoreactive elements 20a to 25a, the irradiation light is blocked by any one of the plurality (two in the figure) for some reason (effect of shadow or the like). , The short-circuit current can be maintained even when the solar cell cannot generate electricity. Also in this case, in order to obtain a substantially short-circuit current, the resistors 9 are connected in parallel as a whole, and the thermistor 5 for correcting the error due to the temperature change is connected.

It was tested whether or not the spectroscopic photon flux densities of the individual bandpass photoelectric elements CH0 to CH5 could be measured by the above configuration. As the experimental device, the one having the configuration shown in FIGS. 1 and 2 (a) and having the base 1 configured in a lump shape was used. Further, as the light-impermeable material, a resin colored in a color extremely close to black (a mixed resin in which urethane is contained in acrylic) was used. The protective member 3 uses a white ABS resin (acrylonitrile-butadiene-styrene copolymer synthetic resin) sheet (thickness 1.0 mm) as a material for attenuating light so as to perform a function similar to that of an ND filter. .. Further, small solar cells are used as the photoreactive elements 20a to 25a, and all the bandpass photoelectric elements CH0 to CH5 have a square surface shape of 5.0 mm × 5.0 mm, and the height including the solar cells is high. The thickness was adjusted to 4.6 mm or less so that the uppermost surface of each of the bandpass photoelectric elements CH0 to CH5 reached the surface of the base 1. The reference photoelectric element CH0 is composed of only a solar cell.

Further, as shown in FIG. 10A, the intensity / amount of the received light is output by the substantially short-circuit current values at both poles of the solar cell, and this is converted into the intensity / amount of light in each wavelength range. In addition, the output intensity / amount was converted into a photon flux density. The conversion formula is based on the conversion method disclosed in Non-Patent Document 1 described above.

<Preliminary experiment>
Since a small solar cell is used as a photoreactive element, a preliminary experiment was conducted to develop a linear correlation between changes in light intensity / amount and changes in output (approximately short-circuit current value). In the preliminary experiment, the irradiation light was attenuated by the ND filter, and the correlation with the substantially short-circuit current value output by the solar cell was confirmed. A solar simulator (XES-40S2 manufactured by Sanaga Denki Co., Ltd.) was used to irradiate five types of light with different intensities. The intensity of the light reaching the small solar cell was measured with a pyranometer, and the substantially short-circuit current value detected by the small solar cell was observed, and then a linear correlation between the two was confirmed. The light ^intensity, the five ranges of ^{600W / m 2 ~1000W / m 2} , ND filter using a commercially available, ND2 (light reduction in transmittance 1/2), to ND4 (transmittance 1/4 Five types were used: ND8 (dimming to 1/8 transmittance), ND16 (dimming to 1/16 transmittance) and ND32 (dimming to 1/32 transmittance).

The above results are shown in FIG. 11 (a). However, "no ND" in the figure means that the light is not dimmed by the ND filter, and "manufacturer's nominal value" is a short circuit of the relationship between the solar radiation intensity and the amount of power generation announced by the solar cell manufacturer. Shown in terms of current value. From this result, it was found that the ND filter that causes a clearly linear correlation to appear is ND32. Therefore, when the above-mentioned white ABS resin sheet (dimming sheet) having a dimming function equivalent to that of ND32 is used, the solar radiation intensity by the solar simulator (XES-40S2 manufactured by Minaga Electric Co., Ltd.) and the substantially short-circuit current value are measured. The graph shows the correlation in the state shown in FIG. 11 (b). From this, it was confirmed that a sheet (dimming sheet) made of a material having a dimming function such as white ABS resin is effective as a substitute for the ND filter.

<Experiment 1>
First, an experiment was conducted in which the intensity for each 100 nm was calculated for the wavelength band from 300 nm to 800 nm when the above-mentioned spectrophotonometer was used. In the experiment, a solar simulator (XES-40S2 manufactured by Sanaga Denki Co., Ltd.) was used, and 1,000 W / m ² was irradiated. The output resistance was adjusted so that each bandpass photoelectric element at this time outputs a voltage of 1 V. Since the output spectrum of the solar simulator can be regarded as the same as the spectrum of sunlight, the intensity of each of 300 nm to 100 nm was calculated by using the integrated value of the spectrum of sunlight for each 100 nm using the light of the solar simulator. The result is shown in FIG. 12 (a). Furthermore, the intensity was converted into a photon flux density. The result is shown in FIG. 12 (b).

<Experiment 2>
Next, an LED that emits a single color of light was irradiated, and the state of spectroscopy was confirmed. As the irradiation light, a blue LED (470 nm, half width 465-475 nm), a green LED (525 nm, half width 520 to 530 nm), and a red LED (625 nm, half width 620-630) were used. In this experiment, the wavelength range of 300 to 800 nm was divided into units of 100 nm, five spectra were performed, and measurements were performed in the entire wavelength range using a reference photoelectric element. The results are shown in FIGS. 13 (a) to 13 (c). Further, for comparison, FIG. 13 (d) shows the result when the base 1 is irradiated with the green LED with an optically transparent material.

As shown in this result, it was found that the spectroscopic state was clear when the colored resin of this experiment was used. This is clear from the fact that the sum of the photon flux densities measured by the individual bandpass photoelectric devices and the photon flux densities in the entire wavelength range measured by the reference photoelectric devices are almost the same. It is also clear from the comparison with FIG. 13 (d) by the comparative experiment.

1,1a, 101,201 Base 1b Side wall 2 Bandpass photoelectric element group 3,103,203 Protective member 4 Coating member 5 Circuit board 6 Processing device 7 Power supply device 8a External device (transmitter)
8b External device (display)
9 Resistors 10, 11, 12, 13, 14, 15, 110, 111, 112, 113, 114, 115, 210a, 211a, 212a, 213a, 214a, 215a Buried areas 10a, 11a, 12a, 13a, 14a, 15a Insulating Sheets 10b, 11b, 12b, 13b, 14b, 15b Embedded Area Components 20a, 21a, 22a, 23a, 24a, 25a Photoreactive Elements 21b, 22b, 23b, 24b, 25b Optical Bandpass Filters 40, 41, 42, 43, 44, 45 Communication part (opening)
50a Case 50b Cover 51, 63, 90 Amplifier circuit (op amp)
52,66 CPU
53 Top plate of lid 54 Peripheral part of lid 55 Window of lid 56 Display screen 61 Timer 62 Temperature sensor 64 Data logger 65 Storage device 67 Output interface 91, 92 Bypass diodes 210b, 211b, 212b, 213b, 214b, 215b Embedded area covering part CH0, CH1, CH2, CH3, CH4, CH5, CH6 Bandpass photoelectric element A, B, C, D, E, F, G, H, I Spectrophotonometer

Claims (6)

A spectrophotonometer in which a plurality of bandpass photoelectric elements are embedded in a base and the photon flux density is measured while dividing into a predetermined wavelength band by each bandpass photoelectric element.
The bandpass photoelectric element includes an optical reaction element and an optical bandpass filter arbitrarily selected according to the wavelength band of light to be measured, and the optical bandpass filter transmits the optical bandpass filter. It is installed on the light receiving surface side of the photoreactive element so that only light is irradiated to the photoreactive element.
The base portion includes a plurality of embedded regions for individually accommodating individual bandpass photoelectric elements, and the embedded region illuminates the entire bandpass photoelectric element except for an appropriate area on the uppermost surface of the bandpass photoelectric element. A band-pass spectrophotonometer characterized by being surrounded in an opaque state. The embedded region has an opening corresponding to the appropriate area on the uppermost surface of the bandpass photoelectric element accommodated therein, and when the bandpass photoelectric element is accommodated inside the embedded region, the embedded region is said to have an opening corresponding to the appropriate area. The uppermost surface of the bandpass photoelectric element is brought to reach the opening of the embedded region, and a predetermined range including the peripheral edge of the opening and the peripheral edge of the uppermost surface of the bandpass photoelectric element is simultaneously provided at the opening of the embedded region. The band-pass spectrophotonometer according to claim 1, further comprising a covering member to be coated. The optical bandpass filter allows spacers made of an optically transparent material to be selectively laminated, and is selectively laminated for each optical bandpass filter constituting each bandpass photoelectric element. The band-pass spectrophotonometer according to claim 2, wherein the uppermost surface of all the bandpass photoelectric elements reaches the opening of the embedded region by the spacer. A circuit for processing the measured value measured by the bandpass photoelectric element, and a dimming member formed of a material arranged on an outer layer from the uppermost surface of the bandpass photoelectric element and attenuating the light transmittance. Is further equipped with
The photoreactive element is an element having a photoelectric conversion function and has a photoelectric conversion function.
The circuit converts the intensity and amount of light measured by the amount of change in the substantially short-circuit current value into the photon flux density based on the electrical output value photoelectrically converted by the photochemical element.
The dimming member is adjusted so that the correlation between the change in the intensity / amount of the received light and the change in the substantially short-circuit current value is within a range showing linearity according to the photoelectric conversion ability of the photoreactive element. The band spectrophotonometer according to any one of claims 1 to 3. Further, a circuit for processing the measured value measured by the bandpass photoelectric element is provided.
The photoreactive element is an element having a photoelectric conversion function and has a photoelectric conversion function.
The circuit converts the intensity and amount of light measured by the amount of change in the substantially short-circuit current value into the photon flux density based on the electrical output value photoelectrically converted by the photoreactive element, and the short-circuit. The band spectrophotonometer according to any one of claims 1 to 3, further comprising an amplifier circuit for amplifying a current value and a high-frequency noise filter for removing noise contained in a substantially short-circuit current. According to claim 4 or 5, the bottom surface of the embedded region is formed of a circuit board having the circuit, and the circuit board covers the bottom of the bandpass photoelectric element in a light-impermeable state. The bandpass photon meter described.

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