JP2020056665A - Ultraviolet sensor and ultraviolet amount measurement device - Google Patents

Abstract

To provide an ultraviolet sensor and an ultraviolet amount measurement device which, by suppressing incident angle dependence of sensitivity in the ultraviolet sensor, uniformalize difference in the sensitivity due to difference in incident angle.SOLUTION: An ultraviolet sensor 10 includes a light receiving element 12 capable of receiving an ultraviolet ray, and attenuates or shields at least a part of the ultraviolet ray which travels approximately orthogonally to a light receiving surface of the light receiving element 12. The ultraviolet sensor 10 includes: a light attenuation/shielding part 20; and a light diffusion part 16 for diffusing the ray traveling toward the light receiving element 12. The light attenuation/shielding part 20 is provided in a manner to completely or partially cover the ultraviolet sensor 10 in a planar view.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an ultraviolet sensor for receiving ultraviolet light and an ultraviolet light amount measuring device.

  A technique for measuring the amount of ultraviolet light by an ultraviolet sensor has been proposed (see Patent Document 1). As an ultraviolet sensor, for example, an ultraviolet sensor is used to estimate the amount of vitamin D produced or to monitor the amount of ultraviolet light in order to prevent excessive damage to the skin due to ultraviolet light.

JP 2012-146706 A

  SUMMARY OF THE INVENTION It is an object of the present invention to provide an ultraviolet sensor and an ultraviolet light amount measuring device which suppress the dependency of the sensitivity of an ultraviolet sensor on the incident angle and make the difference in sensitivity uniform due to the difference in the incident angle.

1. Ultraviolet sensor (1) First ultraviolet sensor The first ultraviolet sensor of the present invention comprises:
Including a light receiving element that can receive ultraviolet light,
An attenuation or light-shielding portion for attenuating or shielding at least a part of ultraviolet light that travels substantially perpendicular to the light-receiving surface of the light-receiving element,
A light diffusion unit for diffusing light traveling toward the light receiving element.

In the present invention,
The incident angle of the ultraviolet ray when the incident angle of the ultraviolet ray incident on the light receiving surface of the ultraviolet ray sensor from the perpendicular direction is 0 ° is x, and the characteristic of the sensitivity f (x) of the light receiving element is x If you have
When the incident angle x of the ultraviolet rays is on the horizontal axis and the sensitivity f1 (x) is on the vertical axis, the graph of the sensitivity f1 (x) has an upwardly convex shape,
The maximum sensitivity I1 _max of the convex portion of the graph of f1 (x) is obtained by multiplying the attenuation or the attenuation ratio D1 _max of the light shielding portion and the light diffusion portion at the incident angle corresponding to the maximum sensitivity I1 _max. Sensitivity I1 _Emax ,
With respect to the sensitivity I11 _{/ 2 of the} light receiving element with respect to ultraviolet rays from the direction of the incident angle x _1/2 of the half width of the graph with respect to the light receiving surface of the light receiving element, sensitivity I1 _{E1 / 2} obtained by multiplying the attenuation ratio D1 _1/2 of the attenuation or shielding portion and a light diffusing portion at a corresponding incident angle x _1/2 is able to take as to satisfy the following equation.
(Equation 1)
(| I1 _Emax −I1 _{E1 / 2} | / I1 _{E1 / 2} ) × 100 ≦ 50
I1 _Emax = I1 _max × D1 _max
I1 _{E 1/2} = I1 _1/2 × D1 _1/2
In the present invention,
In a plan view, the density of the area covered by the attenuation or light shielding portion in the central portion of the light receiving element is larger than the density of the area covered by the attenuation or light shielding portion outside the central portion of the light receiving element. Can be taken.

  In the present invention, the attenuating or light shielding unit may be a metal deposition film or a coating film.

In the present invention,
The attenuating or light-shielding portion is configured by components having a plurality of attenuating or shielding functions,
The components have at least one of a square shape and a circular shape in plan view, and may be arranged in a predetermined pattern.

(2) Second ultraviolet sensor The second ultraviolet sensor of the present invention comprises:
Including a light receiving element that can receive ultraviolet light,
Including a light guide for refracting ultraviolet light that travels substantially perpendicular to the light receiving surface of the light receiving element and guiding the ultraviolet light to the light receiving surface,
The light guide unit includes a light transmitting body and a light diffusing unit for diffusing light passing through the light transmitting body.

In the present invention,
The incident angle of the ultraviolet ray when the incident angle of the ultraviolet ray incident on the light receiving surface of the ultraviolet ray sensor from the perpendicular direction is 0 ° is x, and the characteristic of the sensitivity f2 (x) of the light receiving element is x If you have
When the incident angle x of the ultraviolet rays is set on the horizontal axis and the sensitivity f2 (x) is set on the vertical axis, the graph of the sensitivity f2 (x) has an upwardly convex shape,
The sensitivity I2 _Emax is obtained by multiplying the maximum sensitivity I2 _max of the convex portion of the graph of f2 (x) by the attenuation ratio D2 _max of the light guide portion at an incident angle corresponding to the maximum sensitivity I2 _max. ,
With respect to the sensitivity I21 _/ 2 of the light receiving element with respect to ultraviolet rays from the direction of the incident angle x1 _{/ 2} of the half width of the graph with respect to the light receiving surface of the light receiving element, sensitivity I2 _{E1 / 2} obtained by multiplying the attenuation ratio D2 _1/2 of the light guiding unit at a corresponding incident angle x _1/2 is able to take as to satisfy the following equation.
(Equation 2)
(| I2 _Emax -I2 _{E1 / 2} | / I2 _{E1 / 2} ) × 100 ≦ 50
I2 _Emax = I2 _max × D2 _max
I2 _{E1 / 2} = I2 _1/2 × D2 _1/2

  In the present invention, the light transmitting body may have a transmission ratio of 10% or more.

  In the present invention, the light transmitting body may have a convex lens shape, a shape in which a portion above the convex lens is cut away, or a flat shape.

  In the first and second ultraviolet sensors, the ultraviolet light may be ultraviolet light of sunlight.

In the first and second ultraviolet sensors,
When the sensitivity obtained by multiplying the sensitivity of the light receiving element in relation to the ultraviolet light at a predetermined incident angle and the transmittance of the attenuation or light shielding portion in the relation to the ultraviolet light at the predetermined incident angle, The average value of the effective sensitivities of the sensors at each incident angle in the range of -45 ° to 45 ° when the incident angle of the ultraviolet light incident from the perpendicular direction to the light receiving surface of the sensor is 0 °. Can be within ± 50% of the average value of the light incident angle in the range of −45 ° to 45 °.

2. Ultraviolet light amount measuring device The ultraviolet light amount measuring device of the present invention includes the ultraviolet light sensor of the present invention.

  According to the present invention, it is possible to realize an ultraviolet sensor and an ultraviolet light amount measuring device in which the dependency of the sensitivity of the ultraviolet sensor on the incident angle is suppressed and the difference in sensitivity due to the difference in the incident angle is made uniform.

FIG. 1A is for explaining the sensitivity of the ultraviolet sensor. FIG. 1B shows a graph of the incident angle and the ultraviolet light attenuation rate D. FIG. 1C shows a relationship diagram between the sensitivity I _{Emax of the} ultraviolet sensor and the sensitivity I _{E1 / 2} . It is a figure for explaining an incident angle. It is a figure showing typically an ultraviolet sensor concerning a 1st embodiment. It is a figure showing typically an ultraviolet sensor concerning a 1st embodiment. It is a figure showing typically an ultraviolet sensor concerning a 1st embodiment. It is a figure showing typically an ultraviolet sensor concerning a 1st embodiment. FIG. 3 is a diagram schematically illustrating a planar relationship between an attenuation or light shielding unit and a light receiving element. It is a figure which shows the planar shape of an attenuation or light shielding part typically. FIG. 9A schematically shows a sensitivity curve (f1 (x)) of the light receiving element 12 and a sensitivity curve (f1a (x)) of the light receiving element when the ultraviolet light passes through the light diffusion section 16. This is shown schematically. FIG. 9B schematically shows the attenuation or attenuation characteristics of the light shielding part and the light diffusion part. 5 is a graph schematically showing a graph obtained by multiplying the sensitivity of the light receiving element by the attenuation or the attenuation ratio of the light shielding part and the light diffusion part. FIG. 9 is a diagram schematically illustrating an ultraviolet sensor according to a second embodiment. FIG. 12A schematically shows the incident angle dependent sensitivity characteristics of the light receiving element. FIG. 12B schematically shows the incident angle dependent attenuation rate of the light guide. FIG. 13A schematically shows a graph obtained by multiplying the sensitivity of the light receiving element by the attenuation ratio of the light guide. FIG. 13B is an amplification of the sensitivity of FIG. It is a figure which shows typically the ultraviolet-rays measuring device which concerns on embodiment, FIG.14 (B) is a figure which shows typically the cross section along the A1-A1 line of FIG.14 (A).

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
1. Basic principle explanation The present inventor considers that the ultraviolet light sensor 100 has a specific large sensitivity to ultraviolet light from a certain direction centered on the light receiving surface in a direction perpendicular to the light receiving surface. It has been found that by attenuating or shielding ultraviolet rays, abnormal sensitivity according to the direction of the ultraviolet sensor 100 can be suppressed.

  In addition, the present inventor has made the sensitivity of the ultraviolet sensor 100 uniform at the effective sensitivity of the ultraviolet sensor 100 by blocking or attenuating the ultraviolet light according to the incident angle dependence. It has been found that the abnormal sensitivity of the ultraviolet sensor 100 can be suppressed. More specifically, when the graph obtained when the incident angle of the ultraviolet ray is the x axis and the sensitivity of the ultraviolet sensor 100 is the y axis is the first graph, the incident angle is the x axis, and the attenuation of the ultraviolet ray is It is particularly preferable to attenuate the amount of ultraviolet rays so that the graph obtained with the degree on the y-axis has a shape inverted from the x-axis. That is, when the sensitivity obtained by multiplying the sensitivity of the ultraviolet sensor 100 by the attenuation ratio of the amount of ultraviolet light is used as the effective sensitivity of the ultraviolet sensor 100, by making the effective sensitivity uniform, the orientation of the ultraviolet sensor 100 The corresponding abnormal sensitivity can be suppressed.

As shown in FIG. 1A, when the light receiving element 12 sets the incident angle of the ultraviolet ray incident on the light receiving surface of the ultraviolet sensor 100 from the perpendicular direction to 0 °, the incident angle of the ultraviolet ray is x, and the light receiving element 12 is Consider a case having twelve sensitivity f (x) characteristics. When the incident angle x of ultraviolet rays is set on the horizontal axis and the sensitivity f (x) is set on the vertical axis, the graph of the sensitivity f (x) has an upwardly convex shape (for example, a Gaussian distribution curve), and f (x) against most sensitive _{I max} shape portion of the convex graph, and maximum sensitivity _{I Emax} sensitivity obtained by multiplying the attenuation rate _{D max} of UV at the incident angle corresponding to the I _Emax, to the light receiving surface of the light receiving element 12 With respect to the sensitivity I _1/2 of the light receiving element 12 in the ultraviolet ray from the direction of the incident angle x _1/2 of the half value width of the graph, the attenuation ratio D of the ultraviolet ray at the incident angle x _1/2 corresponding to the half value width D _The sensitivity I _{E1 / 2} obtained by multiplying by _を満 た す may satisfy the following expression.
(Equation 1)
(| I _Emax -I _{E1 / 2} | / I2 _{E1 / 2} ) × 100 ≦ 50
I _Emax = I _max × D _max
I _{E1 / 2} = I _1/2 × D _1/2
Here, the attenuation ratio is indicated by the transmittance.

FIG. 1B shows a graph of the incident angle and the ultraviolet light attenuation rate D. FIG. 1C shows a relationship between the sensitivity I _Emax of the ultraviolet sensor 10 and the sensitivity I _{E1 / 2} . FIG. 2 is a diagram for explaining the incident angle.

  In the present embodiment, sensitivity can be made uniform by attenuating or blocking light from near the vertical direction with high sensitivity, and the ultraviolet sensor 100 suitable for measuring the amount of ultraviolet light can be realized.

  The ultraviolet sensor 100 is particularly useful when measuring ultraviolet rays of sunlight.

2. 1. First Embodiment (1) Configuration Example The ultraviolet sensor 100 according to the first embodiment includes a light receiving element 12 capable of receiving ultraviolet light, an attenuation or light shielding unit 20, and a light diffusion unit 16.

  As the light receiving element 12, a known ultraviolet light receiving element 12 such as a photodiode can be applied. The light receiving element 12 can be provided in the sensor package 14 as shown in FIG.

  The attenuating or light shielding unit 20 is for attenuating or shielding at least a part of the ultraviolet light traveling substantially perpendicularly to the light receiving surface of the light receiving element 12. The material of the attenuation or light shielding unit 20 is not particularly limited as long as it at least attenuates or shields ultraviolet light. The material of the attenuation or light shielding unit 20 may be one that attenuates or shields ultraviolet light and visible light.

Examples of the attenuation or light shielding unit 20 include a resin film, a resin sheet, a metal film, a metal sheet, a metal deposition film, a metal sputtering film, and a carbon film.
Examples of the material of the metal deposition film and the metal sputtered film include aluminum, chromium, nickel, molybdenum, gold, and silver. The carbon film can be composed of, for example, a carbon vapor-deposited film or a diamond-like carbon thin film.

  The attenuation or light shielding unit 20 may be formed by applying or printing a paint.

  The attenuation or light shielding unit 20 may be provided so as to cover the light receiving element 12 in a plan view, as shown in FIGS. More specifically, a mode in which the light receiving element 12 of the light diffusion unit 16 is provided on the surface opposite to the side where the light receiving element 12 is provided (see FIG. 4), and a mode in which the light receiving element 12 is provided on the surface of the light diffusion unit 16 where the light receiving element 12 is provided (see FIG. ), A mode provided on the surface of the sensor package 14 on the light diffusion section 16 side (see FIG. 6), or a mode of a combination of these modes (see FIG. 3). As shown in FIG. 8A, the attenuation or light shielding unit 20 can be provided so as to completely cover the light receiving element 12. An angle α ° formed between a line connecting the end of the light receiving element 12 and the end of the attenuation or light shielding portion 20 and a perpendicular to the light receiving surface of the light receiving element 12 is, for example, 30 ° to 50 °, preferably 40 ° to 45 °. It can be. This makes it possible to attenuate ultraviolet light from a direction perpendicular to the light receiving surface as compared with ultraviolet light from an oblique direction.

  Further, as shown in FIGS. 8B and 8C, when viewed in plan, the density of the area covered by the attenuation or light shielding portion 20 in the central portion of the light receiving element 12 is higher than that of the central portion of the light receiving element 12. It can be made larger than the density of the area covered by the attenuation or the light shielding unit 20 on the outside. This makes it possible to attenuate the ultraviolet light from the direction perpendicular to the light receiving surface as compared with the ultraviolet light from the oblique direction.

  The attenuation or light shielding unit 20 is composed of a plurality of components having an attenuation or shielding function, and the components are square or substantially square (FIG. 8B) and circular or substantially square (FIG. C)), and may be arranged in a predetermined pattern. The area of the components in the central portion can be larger than the components outside the central portion. More specifically, the area of the component can be reduced from the center to the outside. This makes it possible to attenuate ultraviolet light from a direction perpendicular to the light receiving surface as compared with ultraviolet light from an oblique direction.

  The components of the attenuation or light shielding unit 20 are concentric, such as concentric circles (FIG. 8D), concentric substantially circular shapes, concentric square shapes (FIG. 8E), and concentric substantially rectangular shapes. It may be polygonal.

  The thickness of the attenuation or light-shielding portion 20 varies depending on the attenuation or light-shielding function of the material and the method of forming the material. However, in the case of a vapor-deposited film, the thickness can be, for example, 0.5 μm to 10 μm. Can be, for example, 5 to 20 μm.

  The light diffusing unit 16 is for diffusing light traveling toward the light receiving element 12, and is not particularly limited as long as it has a light diffusing function, and can be made of, for example, an acrylic plate or a cycloolefin plate.

(2) Characteristics In the ultraviolet sensor 100, the light receiving element 12 is defined as x when the incident angle of ultraviolet light incident from the perpendicular direction to the light receiving surface of the ultraviolet sensor 100 is 0 °, and the light receiving element 12 is In the case of having the characteristic of the sensitivity f (x), when the incident angle x of the ultraviolet ray is on the horizontal axis and the sensitivity f1 (x) is on the vertical axis, the graph of the sensitivity f1 (x) has an upwardly convex shape. The maximum sensitivity I1 _max of the convex portion of the graph of f1 (x) is multiplied by the attenuation at the incident angle corresponding to the maximum sensitivity I1 _max or the attenuation ratio D1 _max of the light shielding unit 20 and the light diffusion unit 16. The sensitivity I1 _Emax obtained by the above is attenuated or shielded from the sensitivity I1 _1/2 of the light receiving element 12 in the ultraviolet light from the direction of the incident angle x _1/2 of the half width of the graph with respect to the light receiving surface of the light receiving element 12. In part 20 Kicking and sensitivity I1 _{E1 / 2} obtained by multiplying the attenuation ratio D1 _1/2 of attenuation or shielding portion 20 and the light diffusion portion 16 at an incident angle x _1/2 corresponding to the half value width, to satisfy the following formula it can.
(Equation 1)
(| I1 _Emax −I1 _{E1 / 2} | / I1 _{E1 / 2} ) × 100 ≦ 50
I1 _Emax = I1 _max × D1 _max
I1 _{E 1/2} = I1 _1/2 × D1 _1/2
“(| I1 _Emax −I1 _{E1 / 2} | / I1 _{E1 / 2} ) × 100” is preferably 40 or less, more preferably 30 or less.

  FIG. 9A schematically shows the sensitivity curve (f1 (x)) of the light receiving element 12, and the sensitivity curve (f1a (x)) of the light receiving element 12 when the ultraviolet light passes through the light diffusion section 16. Are schematically shown. FIG. 9B schematically shows the attenuation or attenuation characteristics of the light shielding unit 20 and the light diffusion unit 16. FIG. 10 schematically shows a graph obtained by multiplying the sensitivity of the light receiving element 12 by the attenuation or the attenuation ratio of the light shielding unit 20 and the light diffusion unit 16.

3. 2. Second Embodiment (1) Configuration Example As shown in FIG. 11, an ultraviolet sensor 100 according to a second embodiment includes a light receiving element 12 that can receive ultraviolet light. And a light guide portion 30 for refracting ultraviolet light traveling substantially vertically and guiding the ultraviolet light to the light receiving surface.

  As the light receiving element 12, a known ultraviolet light receiving element 12 such as a photodiode can be applied. The light receiving element 12 can be provided in the sensor package 14 as shown in FIG.

  The light guide unit 30 may include a light diffusion unit 36 and a light transmitting body 32 having a predetermined transmission ratio. The ultraviolet sensor 100 can be arranged in the order of the light receiving element 12, the light diffusion section 36, and the light transmitting body 32.

  The light diffusion section 36 is for diffusing light traveling toward the light receiving element 12, and is not particularly limited as long as it has a light diffusion function. The material of the light transmitting body can be made of, for example, ultraviolet transmitting glass, plastic such as acrylic resin or cycloolefin polymer, or the like.

  The light transmitting body may have a light diffusion function in which at least a fine powder (for example, titanium oxide, carbon, metal powder, or the like) of a material that blocks ultraviolet light is used as a filler.

  The surface of the light transmitting body may have a predetermined roughness. The surface roughness may be, for example, Ra 5 to 25 μm in terms of surface roughness Ra.

  The transmission ratio of the light transmitting body 32 can be, for example, 10% or more, preferably 10 to 80%. As shown in FIG. 11, the light transmitting body 32 has a convex lens shape (FIG. 11A), a shape in which a portion above the convex lens is cut off (FIG. 11B), or a flat plate shape (FIG. 11C). It can be.

(2) Characteristics In the ultraviolet sensor 100, the light receiving element 12 is defined as x when the incident angle of ultraviolet light incident from the perpendicular direction to the light receiving surface of the ultraviolet sensor 100 is 0 °, and the light receiving element 12 is When the sensitivity f2 (x) has the characteristic of f2 (x), the graph of the sensitivity f2 (x) has an upward convex shape when the incident angle x of the ultraviolet ray is the horizontal axis and the sensitivity f2 (x) is the vertical axis. The sensitivity I2 _Emax obtained by multiplying the maximum sensitivity I2 _max of the convex portion of the graph of f2 (x) by the attenuation ratio D2 _max of the light guide 30 at an incident angle corresponding to the maximum sensitivity I2 _max. In relation to the sensitivity I2 _1/2 of the light receiving element 12 with respect to the ultraviolet rays from the direction of the incident angle x _1/2 of the half value width of the graph with respect to the light receiving surface of the light receiving element 12, Corresponding The sensitivity I2E1 _{/ 2} obtained by multiplying the attenuation ratio D21 _{/ 2} of the light guide unit 30 at the incident angle x1 _{/ 2} can satisfy the following expression.
(Equation 2)
(| I2 _Emax -I2 _{E1 / 2} | / I2 _{E1 / 2} ) × 100 ≦ 50
I2 _Emax = I2 _max × D2 _max
I2 _{E1 / 2} = I2 _1/2 × D2 _1/2
Here, “(| I2 _Emax −I2 _{E1 / 2} | / I2 _{E1 / 2} ) × 100” is preferably 40 or less, more preferably 30 or less.

  FIG. 12A schematically shows the incident angle dependent sensitivity characteristics of the light receiving element 12. FIG. 12B schematically shows the incident angle dependent attenuation rate of the light guide 30. FIG. 13A schematically shows a graph obtained by multiplying the sensitivity of the light receiving element 12 by the attenuation ratio of the light guide unit 30. FIG. 13B is an amplification of the sensitivity of FIG.

4. Application Example As shown in FIG. 14, the ultraviolet ray amount measuring apparatus 100 includes a housing 40 and the ultraviolet ray sensor 100 according to the embodiment. A plurality of ultraviolet sensors 100 may be provided in the housing 40. By providing a plurality of ultraviolet sensors 100, the amount of ultraviolet light can be measured at a wider angle. The angle formed by the direction in which the ultraviolet sensor 100 faces can be, for example, 70 ° to 90 °. Specifically, as shown in FIG. 14A, four ultraviolet sensors 100 can be provided in the ultraviolet ray amount measuring device. Each arrow in FIG. 14A indicates the vertical direction of the light receiving surface of the light receiving element 12. As shown in FIG. 14B, ultraviolet sensors 100 may be provided on the upper and lower surfaces of the ultraviolet light amount measuring device 100. By arranging a plurality of ultraviolet sensors 100, ultraviolet rays from all directions can be received.

  The above embodiment can be variously modified within the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 Ultraviolet sensor 12 Light receiving element 14 Sensor package 16 Light diffusing part 20 Attenuation or light shielding part 30 Light guide part 32 Light transmitting body 36 Light diffusing part 40 Housing 100

Claims (12)

Including a light receiving element that can receive ultraviolet light,
An attenuation or light-shielding portion for attenuating or shielding at least a part of ultraviolet light that travels substantially perpendicular to the light-receiving surface of the light-receiving element,
A light diffusion unit for diffusing light traveling toward the light receiving element. In claim 1,
The incident angle of the ultraviolet ray when the incident angle of the ultraviolet ray incident on the light receiving surface of the ultraviolet ray sensor from the perpendicular direction is 0 ° is x, and the characteristic of the sensitivity f (x) of the light receiving element is x If you have
When the incident angle x of the ultraviolet rays is on the horizontal axis and the sensitivity f1 (x) is on the vertical axis, the graph of the sensitivity f1 (x) has an upwardly convex shape,
The maximum sensitivity I1 _max of the convex portion of the graph of f1 (x) is obtained by multiplying the attenuation or the attenuation ratio D1 _max of the light shielding portion and the light diffusion portion at the incident angle corresponding to the maximum sensitivity I1 _max. Sensitivity I1 _Emax ,
With respect to the sensitivity I11 _{/ 2 of the} light receiving element with respect to ultraviolet rays from the direction of the incident angle x _1/2 of the half width of the graph with respect to the light receiving surface of the light receiving element, corresponding the incident angle sensitivity obtained by multiplying the attenuation ratio D1 _1/2 of the attenuation or shielding portion and a light diffusing portion in the x _1/2 I1 _{E1 / 2} is, the ultraviolet sensor that satisfies the following expression.
(Equation 1)
(| I1 _Emax −I1 _{E1 / 2} | / I1 _{E1 / 2} ) × 100 ≦ 50
I1 _Emax = I1 _max × D1 _max
I1 _{E 1/2} = I1 _1/2 × D1 _1/2 In claim 1 or 2,
As viewed in plan, the density of the area covered by the attenuation or light-shielding portion in the central portion of the light-receiving element is larger than the density of the area covered by the attenuation or light-shielding portion outside the central portion of the light-receiving element. . In any one of claims 1 to 3,
The ultraviolet sensor, wherein the attenuating or light shielding unit is a metal deposition film or a coating film. In any one of claims 1 to 4,
The attenuating or light-shielding portion is configured by components having a plurality of attenuating or shielding functions,
The ultraviolet sensor, wherein the constituent elements have at least one of a square shape and a circular shape in plan view, and are arranged in a predetermined pattern. Including a light receiving element that can receive ultraviolet light,
Including a light guide for refracting ultraviolet light that travels substantially perpendicular to the light receiving surface of the light receiving element and guiding the ultraviolet light to the light receiving surface,
The ultraviolet sensor, wherein the light guide unit includes a light transmitting body and a light diffusing unit for diffusing light passing through the light transmitting body. In claim 6,
The incident angle of the ultraviolet ray when the incident angle of the ultraviolet ray incident on the light receiving surface of the ultraviolet ray sensor from the perpendicular direction is 0 ° is x, and the characteristic of the sensitivity f2 (x) of the light receiving element is x If you have
When the incident angle x of the ultraviolet rays is set on the horizontal axis and the sensitivity f2 (x) is set on the vertical axis, the graph of the sensitivity f2 (x) has an upwardly convex shape,
The sensitivity I2 _Emax is obtained by multiplying the maximum sensitivity I2 _max of the convex portion of the graph of f2 (x) by the attenuation ratio D2 _max of the light guide portion at an incident angle corresponding to the maximum sensitivity I2 _max. ,
With respect to the sensitivity I21 _/ 2 of the light receiving element with respect to ultraviolet rays from the direction of the incident angle x1 _{/ 2} of the half width of the graph with respect to the light receiving surface of the light receiving element, corresponding sensitivity I2 _{E1 / 2} obtained by multiplying the attenuation ratio _{D2 1/2} of the light guiding portion at an incident angle _{x 1/2} is UV sensor that satisfies the following expression.
(Equation 2)
(| I2 _Emax -I2 _{E1 / 2} | / I2 _{E1 / 2} ) × 100 ≦ 50
I2 _Emax = I2 _max × D2 _max
I2 _{E1 / 2} = I2 _1/2 × D2 _1/2 In claim 6 or 7,
The light transmitting body is an ultraviolet sensor having a transmission ratio of 10% or more. In any one of claims 6 to 8,
An ultraviolet sensor in which the light transmitting body has a convex lens shape, a shape in which a portion above the convex lens is cut away, or a flat plate shape. In any one of claims 1 to 9,
An ultraviolet sensor, wherein the ultraviolet light is ultraviolet light of sunlight. In any one of claims 1 to 10,
When the sensitivity obtained by multiplying the sensitivity of the light receiving element in relation to the ultraviolet light at a predetermined incident angle and the transmittance of the attenuation or light shielding portion in the relation to the ultraviolet light at the predetermined incident angle, The average value of the effective sensitivities of the sensors at each incident angle in the range of -45 ° to 45 ° when the incident angle of the ultraviolet light incident from the perpendicular direction to the light receiving surface of the sensor is 0 °. Is an ultraviolet sensor having an incident angle of light within ± 50% of an average value in a range of −45 ° to 45 °. An ultraviolet ray measuring device including the ultraviolet ray sensor according to claim 1.

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