WO2014162548A1

WO2014162548A1 - Integrating sphere

Info

Publication number: WO2014162548A1
Application number: PCT/JP2013/060246
Authority: WO
Inventors: 望月　学; 昭一藤森
Original assignee: パイオニア株式会社; 株式会社パイオニアＦａ
Priority date: 2013-04-03
Filing date: 2013-04-03
Publication date: 2014-10-09
Also published as: JPWO2014162548A1

Abstract

Provided is an integrating sphere in which light incident on a through-hole for a light receiving part for measuring a light quantity and a wavelength measuring part for measuring a wavelength is prevented from being emitted again from the through-hole without being incident on the light receiving part or the wavelength measuring part due to reflection or the like. An integrating sphere (2) comprises an integrating sphere body (3) having a spherical space therein, a first through-hole (31c) for guiding light to be measured into the spherical space, and a second through-hole (33c) for guiding the light in the spherical space to a light receiving part (7), and in the second through-hole (33c), a wavelength measuring part (9) for measuring the wavelength of the light is provided in addition to the light receiving part (7).

Description

Integrating sphere

The present invention relates to an integrating sphere used for measuring the characteristics of light.

Patent Document 1 discloses a colorimeter technique.

Japanese Unexamined Patent Publication No. 64-86028

However, the apparatus described in Patent Document 1 does not describe a configuration in which a light receiving unit that measures the amount of light and a wavelength measuring unit that measures the wavelength are provided.
When providing a light receiving unit that measures the amount of light and a wavelength measuring unit that measures the wavelength, a through hole is provided in the integrating sphere for each of the light receiving unit that measures the normal amount of light and the wavelength measuring unit that measures the wavelength. It is usual to provide it.
In addition, light that has entered the through hole for the light receiving unit that measures the amount of light and the wavelength measuring unit that measures the wavelength is not incident on the light receiving unit or the wavelength measuring unit due to reflection or the like, but is emitted again from the through hole. There is a possibility that proper measurement cannot be performed.

The present invention has been made in view of the above problems, and an example of the purpose thereof is that light incident on a through hole for a light receiving unit for measuring the amount of light and a wavelength measuring unit for measuring the wavelength is received by reflection or the like. It is to provide an integrating sphere that is not incident on the part or the wavelength measuring part and is not emitted again from the through hole.

The integrating sphere according to the first aspect of the present invention includes an integrating sphere main body having a spherical space therein, a first through hole for guiding measurement target light into the spherical space, and a light receiving unit for receiving the light in the spherical space. A second through hole for guiding light to the light source, and a wavelength measuring unit for measuring the wavelength of light in addition to the light receiving unit is disposed in the second through hole.

The integrating sphere according to the second aspect of the present invention includes an integrating sphere main body having a spherical space therein, a first through hole for guiding measurement target light into the spherical space, and a light receiving unit for receiving the light in the spherical space. A second through hole for guiding light to the side, and the side surface of the second through hole is formed so as to regularly reflect the incident light. It is formed in a truncated cone shape larger than the surface on the main body side.

It is explanatory drawing of the 1st Embodiment of this invention. It is explanatory drawing explaining the function of an integrating sphere. It is explanatory drawing of a comparative example. It is explanatory drawing of 2nd Embodiment. It is explanatory drawing of 3rd Embodiment. It is explanatory drawing of 4th Embodiment.

<First Embodiment>
FIG. 1 is an explanatory diagram of a first embodiment of the present invention.
FIG. 2 is an explanatory diagram for explaining the function of the integrating sphere 2.
FIG. 3 is an explanatory diagram of a comparative example.

Hereinafter, the first embodiment of the present invention will be described in detail with reference to FIG.
The integrating sphere 2 has an integrating sphere body 3, a first through hole portion 31, and a second through hole portion 33.

The integrating sphere main body 3 has a spherical hollow space.
The integrating sphere body 3 is formed so that the integrating sphere inner surface 3a, which is the surface on the hollow space side, diffusely reflects (diffuse reflection).
The hollow space formed by the integrating sphere inner surface 3a of the integrating sphere main body 3 needs to be spherical, but the external shape does not necessarily have to be a sphere.
A first through hole portion 31 and a second through hole portion 33 are connected to the integrating sphere body 3.

A cylindrical hollow space is formed in the first through hole portion 31. In order to form this hollow space, a first through hole 31 c is formed that penetrates from the outside of the first through hole portion 31 to the hollow space of the integrating sphere main body 3.
The integrating sphere 2 receives the light to be measured through the first through hole 31c of the first through hole 31.
In addition, although this 1st through-hole part 31 is a cylindrical shape in this embodiment, it may be prismatic shape (triangular prism, quadrangular prism, pentagonal prism, or more prismatic shapes).
Furthermore, a cylindrical outer surface formed by the first through holes 31c is referred to as a first outer surface 31b. The cylindrical inner surface (integral sphere body 3 side) formed by the first through hole 31c is referred to as a first inner surface 31a.

A cylindrical hollow space is formed in the second through-hole portion 33. In order to form this hollow space, a second through hole 33 c is formed that penetrates from the outside of the second through hole portion 33 to the hollow space of the integrating sphere main body 3.
The integrating sphere 2 outputs the light to be measured through the second through hole 33c of the second through hole 33.
Here, the light passing through the second through-hole portion 33 is obtained after the light passing through the first through-hole portion 31 is diffusely reflected at the integrating sphere inner surface 3a at least once. The reason for this will be described later in detail.
The second through-hole portion 33 has a cylindrical shape in this embodiment, but may have a prismatic shape (triangular prism, quadrangular prism, pentagonal prism, or more prismatic shapes).
Furthermore, a cylindrical outer surface formed by the second through hole 33c is referred to as a second outer surface 33b. A cylindrical inner surface (integral sphere body 3 side) formed by the second through hole 33c is referred to as a second inner surface 33a.

The light receiving unit 7 and the wavelength measuring unit 9 are disposed in the second through hole 33c.
The light receiving unit 7 is used to measure the amount of light after being diffusely reflected by the integrating sphere body 3. For example, a photodetector may be used for the light receiving unit 7. Further, a CCD or the like may be used.
The wavelength measuring unit 9 is used to measure the wavelength of light after being diffusely reflected by the integrating sphere body 3.
The wavelength measuring unit 9 allows light to enter from the front end surface of the optical fiber, guide the light through the optical fiber, guide it to the wavelength measuring device, and actually measure the wavelength with the wavelength measuring device. good.
Further, a light guide member may be further used at the tip of the optical fiber so that the light guide member first guides the light to the optical fiber and then guides it to the wavelength measuring device. As the light guide member, a member that reflects the inner surface of the cylindrical member may be used, or a member (for example, glass) that reflects the extended inner surface may be used. Furthermore, the light guide member may be formed of a member that reflects the surface of a cylindrical or prismatic side surface.

In FIG. 1, the incident surface 9a of the wavelength measuring unit 9 is formed so as to protrude into the second through hole 33c.
The wavelength measuring unit 9 passes through the second through hole 33.
When the angle between the light guide direction of the wavelength measuring unit 9 and the direction of the central axis of the second through hole 33c on the light receiving unit 7 side is θ1, the configuration is such that θ1 <90 °.
As a result, the wavelength measuring unit 9 can more smoothly guide light to a part to be actually measured such as a spectroscope.

Here, the function of the integrating sphere 2 will be briefly described with reference to FIG.
The integrating sphere 2 outputs diffused light (emitted from the second through hole 33c) by repeating diffuse reflection of the incident light (incident from the first through hole 31c).
That is, the integrating sphere 2 can measure light in which the polarization, light distribution, wavelength, and the like of light in the direction of the measurement object 101 (for example, LED) are averaged.
In addition, the following formula | equation is materialized about the light quantity output with respect to the light quantity input at this time.
Output light quantity / input light quantity ∝ Output port area (second outer surface 33b of second through hole 33c) / total surface area inside integrating sphere (= (in the case of FIG. 1) 3a + 31a + 33a)

As shown in FIG. 1, light from the measurement object 101 (LED) is introduced into the integrating sphere 2 from the first through hole 31c.

The tip of the probe 11 contacts the electrode of the measurement object 101 (for example, LED). The probe 11 is used for supplying power to the measurement object 101 to emit light.
However, the probe 11 is not essential when the measurement object 101 does not require the probe 11 or the like.
Further, the measurement object 101 may be separated from the first through hole 31c as shown in FIG. Furthermore, the measurement object 101 may be disposed inside the first through hole 31c.

When measuring the amount of light and the wavelength, it usually has a configuration as in the comparative example of FIG.
FIG. 3A is a side cross-sectional view that is the same as FIG. FIG. 3B is a cross-sectional view taken along the line BB in FIG.

In the comparative example, a second through hole 33c for the light receiving unit 7 is formed as shown in FIG. In addition, in the comparative example, a third through hole 35c for the wavelength measuring unit 9 is formed.
In the comparative example, since the second through hole 33c and the third through hole 35c are formed at different positions, the light incident on the light receiving unit 7 and the light incident on the wavelength measuring unit 9 have different characteristics. There is a possibility that.
Furthermore, since the second through hole 33c and the third through hole 35c are provided separately, the light incident on the integrating sphere 2 is dispersed, so that the light incident on the light receiving unit 7 and the wavelength measuring unit 9 The amount will decrease.
On the other hand, in the first embodiment, since the light receiving unit 7 and the wavelength measuring unit 9 are formed in the same second through hole 33c, the light receiving unit 7 and the wavelength measuring unit 9 have the same characteristics. Can be measured.
In the first embodiment, since the light receiving unit 7 and the wavelength measuring unit 9 are formed in the same second through hole 33c, it is possible to reduce the decrease in the light amount.
In the first embodiment, the inner peripheral surfaces (side surfaces) of the first through hole 31c and the second through hole 33c are formed so as to be diffusely reflected.

<Second Embodiment>
FIG. 4 is an explanatory diagram of the second embodiment.

In the first embodiment, the light reflected by the incident surface 9a of the wavelength measuring unit 9 returns to the inside of the integrating sphere body 3 from the second inner surface 33a of the second through hole 33c again without entering the light receiving unit 7. There may be a small part that ends up.
In order to further reduce this influence, in the second embodiment, as shown in FIG. 4, the incident surface 9a is formed so as to contact the second through hole 33c.
Thereby, in the light quantity measurement by the light receiving unit 7, it is possible to reduce the adverse effect of the wavelength measuring unit 9 and the light receiving unit 7 can obtain a more accurate measurement value.
Specifically, when the angle between the normal direction of the incident surface 9a of the wavelength measuring unit 9 and the direction of the central axis of the second through hole 33c on the light receiving unit side is θ2, θ2 = 90 °. Configure as follows. When the angle between the light guide direction of the wavelength measuring unit 9 and the direction of the central axis of the second through hole 33c on the light receiving unit 7 side is θ1, the configuration is such that θ1 <90 °.
When the shape of the second through hole 33c is a shape such as a truncated cone, θ2 may not be 90 °.
Furthermore, the wavelength measuring unit 9 may penetrate into the second through hole 33c.

<Third Embodiment>
FIG. 5 is an explanatory diagram of the third embodiment.

In the first embodiment and the second embodiment, the inner peripheral surface (side surface) of the second through hole 33c is formed so as to be diffusely reflected.
However, in the case of diffuse reflection, light incident on the inside of the second through hole 33c is emitted from the second internal surface 33a due to diffuse reflection.
Therefore, a regular reflection material 33d for regular reflection is formed on the inner peripheral surface (side surface) of the second through hole.
As a result, the light once incident on the second through hole 33c can be more reliably guided to the light receiving unit 7.

<Fourth embodiment>
FIG. 6 is an explanatory diagram of the fourth embodiment.

In the third embodiment, the shape of the second through hole 33c is a simple columnar shape.
However, in order to prevent the light incident on the second through hole 33c from being emitted from the second inner surface 33a, in the fourth embodiment, the shape of the second through hole 33c is a truncated cone shape as shown in FIG. It is said.
More specifically, the surface of the truncated cone on the integrating sphere main body 3 side is formed to have a smaller area than the surface of the truncated cone on the light receiving unit 7 side.
Since the fourth embodiment has such a truncated cone shape, the light once incident on the second through hole 33 c can be more reliably guided to the light receiving unit 7.
In the fourth embodiment, the inner peripheral surface of the second through hole 33c is formed so as to be regularly reflected.

<Configuration and Effect of Embodiment>
The integrating sphere 2 of the present embodiment includes an integrating sphere main body 3 having a spherical space therein, a first through hole 31c for guiding measurement target light into the spherical space, and a light receiving unit 7 for receiving the light in the spherical space. And a second through hole 33c for guiding light to the second through hole 33c. In addition to the light receiving unit 7, a wavelength measuring unit 9 for measuring the wavelength of light is disposed in the second through hole 33c.
Since it has such a configuration, light that has entered the through hole for the light receiving unit for measuring the light amount and the wavelength measuring unit for measuring the wavelength does not enter the light receiving unit or the wavelength measuring unit due to reflection or the like. There is an effect that it is possible to provide an integrating sphere that is not emitted again from the hole.

The second through-hole 33c has a cylindrical shape, the wavelength measuring unit 9 has an incident surface 9a on which the light of the measurement object 101 is incident, and the incident surface 9a is second from the side surface of the second through-hole 33c. It arrange | positions so that it may contact | abut to the through-hole 33c, or it may be located in the internal space of the 2nd through-hole 33c from the side part of the 2nd through-hole 33c.
With this configuration, the wavelength measuring unit 9 can be disposed without reducing the light receiving area of the light receiving unit 7.

The normal direction of the incident surface 9a is formed to have a predetermined angle with respect to the central axis of the second through hole 33c.
Since it has such a structure, it becomes possible to reduce that the light incident on the incident surface 9a is reflected and emitted again from the second through hole 33c.

The light guide direction of the light incident on the wavelength measuring unit 9 from the incident surface 9a is formed to have a predetermined angle with respect to the central axis of the second through hole 33c.
Since it has such a structure, it becomes possible to guide the light of a measuring object more smoothly.

The normal direction of the incident surface 9a is formed at right angles to the central axis of the second through hole 33c.
Since it has such a configuration, it is also possible to provide the wavelength measuring unit 9 without hindering the light guide in the second through hole 33c.

The side surface of the second through hole 33c is formed so as to regularly reflect incident light.
With such a configuration, it is possible to more reliably guide the light once incident on the second through hole 33c to the light receiving unit 7.

The second through hole 33c is formed in a truncated cone shape having a surface on the light receiving unit side larger than a surface on the integrating sphere main body side.
Since it has such a structure, it becomes possible to guide the light once incident on the second through hole 33c to the light receiving unit 7 more reliably.

An integrating sphere body 3 having a spherical space therein, a first through hole 31c for guiding the measurement target light into the spherical space, and a second through for guiding the light in the spherical space to the light receiving unit 7 And the side surface of the second through hole 33c is formed so as to regularly reflect incident light, and the second through hole 33c has a surface on the light receiving unit 7 side on the surface of the integrating sphere body 3 side. It is formed in a larger truncated cone shape.
Since it has such a configuration, light that has entered the through hole for the light receiving unit for measuring the light amount and the wavelength measuring unit for measuring the wavelength does not enter the light receiving unit or the wavelength measuring unit due to reflection or the like. There is an effect that it is possible to provide an integrating sphere that is not emitted again from the hole.

Note that the integrating sphere inner surface 3a of the integrating sphere 2 is described as diffusely reflecting. However, the integrating sphere inner surface 3a may be regularly reflected.

DESCRIPTION OF SYMBOLS 1 Optical characteristic measuring apparatus 2 Integrating sphere 3 Integrating sphere main body 3a Integral sphere inner surface 5 Light guide part constituent member 7 Light receiving part 9 Wavelength measuring part 9a Incident surface 31 First through hole part 31c First through hole 33 Second through hole part 33c Second through hole 101 Object to be measured

Claims

An integrating sphere body having a spherical space inside;
A first through hole for guiding measurement target light into the spherical space;
A second through hole for guiding the light in the spherical space to the light receiving unit;
Have
The second through hole is provided with a wavelength measuring unit for measuring the wavelength of light in addition to the light receiving unit.
The second through hole has a cylindrical shape;
The wavelength measuring unit has an incident surface on which light to be measured is incident,
The incident surface is
In contact with the second through hole from the side surface of the second through hole,
Or
In order to be located in the internal space of the second through hole from the side surface portion of the second through hole,
The integrating sphere according to claim 1 disposed.
The integrating sphere according to claim 2, wherein the normal direction of the incident surface is formed to have a predetermined angle with respect to a central axis of the second through hole.
The integrating sphere according to claim 3, wherein a light guide direction of light incident on the wavelength measurement unit from the incident surface is formed to have a predetermined angle with respect to a central axis of the second through hole.
The integrating sphere according to claim 4, wherein a normal direction of the incident surface is formed at a right angle to a central axis of the second through hole.
The integrating sphere according to claim 1, wherein a side surface of the second through hole is formed so as to regularly reflect incident light.
The integrating sphere according to claim 6, wherein the second through hole is formed in a truncated cone shape having a surface on the light receiving unit side larger than a surface on the integrating sphere main body side.
An integrating sphere body having a spherical space inside;
A first through hole for guiding measurement target light into the spherical space;
A second through hole for guiding the light in the spherical space to the light receiving unit;
Have
The side surface of the second through hole is formed so as to regularly reflect incident light,
The second through hole is formed as a truncated cone having a surface on the light receiving unit side larger than a surface on the integrating sphere main body side.