JP2024041222A - Light scattering measurement device - Google Patents

Abstract

[Problem] To provide a light scattering measurement device equipped with an optical element holder that contributes to miniaturization of light scattering measurement devices. [Solution] The device includes a light source, a sample cell that contains a sample and into which light from the light source is incident, a detection unit that detects the outgoing light emitted from the sample cell, an optical element holder 4 that has a rotation axis AR perpendicular to a plane determined by a path LP of the outgoing light from the sample cell toward the detection unit and that holds a plurality of optical elements including a first optical element 401-1 and a second optical element 402-2 that are respectively provided around the rotation axis so as to face the rotation axis, and an optical element holder support unit that supports the optical element holder so as to be rotatable around the rotation axis, and the optical element holder is rotatable at least between a first position in which the first optical element is located on the path and a second position in which the second optical element is located on the path. [Selected Figure] Figure 4

Description

The present invention relates to a light scattering measuring device.

In light scattering measurement devices, an optical element holder that holds an optical element that changes optical properties such as the polarization direction may be provided between the sample cell and the detection unit. For example, when using a light scattering measurement device to measure the anisotropy of a measurement sample, a polarizing element holder is provided between the sample cell and the detection unit.

When an optical element holder holds two or more types of optical elements, it is necessary to switch between these optical elements. For example, if you want to extract and measure a vertical linearly polarized light component and a horizontal linearly polarized light component from scattered light from a measurement sample, you can use a polarizing element whose polarization axis is vertical, and a polarization element whose polarization axis is horizontal. It is necessary to switch between polarizing elements.

Conventionally, various optical element holders that enable mutual switching between a plurality of optical elements have been studied. For example, in the field of variable polarization wafer inspection, a technique is known in which the polarization direction is switched by horizontally sliding a plate-shaped holder in which a plurality of polarization elements are arranged (see FIG. 3 of Patent Document 1 below). . In addition, in the field of measuring the appearance of birefringent fibers, multiple polarizing elements are placed on a disc-shaped holder with a rotation axis parallel to the optical path, and the direction of polarization is determined by rotating this holder around the rotation axis. A switching technique (see FIG. 3A of Patent Document 2 below) is known.

Special table 2015-516574 JP2011-069805

On the other hand, conventional optical element holders such as those described in the above-mentioned patent documents require a large space for installation. This is because in conventional optical element holders, a plurality of optical elements are provided on the same plane. Specifically, in a conventional optical element holder, a plurality of optical elements are arranged on a plate-shaped or disk-shaped substrate. All of these optical elements face the same direction, that is, the same direction as the path of light incident toward the optical element holder. Here, in the optical element holder, only one of the plurality of optical elements is involved in measurement, that is, placed on the optical path. Among the plurality of optical elements, the optical elements other than this one optical element occupy a certain space in the width direction of the substrate in the optical element holder, although they do not participate in the measurement. As a result, a dead space is generated for that certain amount of space.

Therefore, when the conventional optical element holder is used, a problem arises in that the light scattering measurement apparatus itself becomes larger. Particularly, when the light scattering measuring device has two or more detection sections, that is, when performing measurement using a multi-angle light scattering method, two or more optical element holders are also required. In this case, if a conventional optical element holder is used, the dead space increases, and the size of the measuring device becomes more significant.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a light scattering measuring device equipped with an optical element holder that contributes to miniaturization of the light scattering measuring device.

(1) The light scattering measuring device according to the present invention includes a light source, a sample cell that houses a sample and into which light from the light source enters, a detection unit that detects the output light emitted from the sample cell, and the sample cell. a first optical element and a second optical element each having a rotation axis perpendicular to a plane determined by a path of the emitted light heading from the cell to the detection unit, and each of which is provided around the rotation axis so as to face the rotation axis; The optical element holder includes an optical element holder that holds a plurality of optical elements including an optical element, and an optical element holder support that supports the optical element holder so as to be rotatable around the rotation axis, and the optical element holder includes: It is rotatable between at least a first attitude in which the first optical element is located on the path and a second attitude in which the second optical element is located on the path.

(2) In the light scattering measurement device of (1), the optical element holder has a main body, and holds the plurality of optical elements on a side surface of the main body, and the optical element holder has a main body, and the plurality of optical elements are held on the side surface of the main body. A plurality of apertures may be provided, including a first aperture formed on the opposite side of the first optical element and a second aperture formed on the opposite side of the second optical element.

(3) In the light scattering measuring device of (2), the rotation axis is located on the path, is sandwiched between the first optical element and the first aperture, and is connected to the second optical element. It may be sandwiched between the second opening and the second opening.

(4) In the light scattering measuring device of (3), the plurality of optical elements and the plurality of apertures may be arranged at equal angular intervals all around the rotation axis.

(5) In the light scattering measuring device according to any one of (1) to (4), the optical element holder may include a polygonal portion in its cross section.

(6) In the light scattering measuring device according to any one of (2) to (5), the plurality of apertures may include a third aperture and a fourth aperture that face each other.

(7) In the light scattering measuring device according to any one of (1) to (6), the first optical element and the second optical element may each be a polarizing element.

(8) In the light scattering measuring device according to any one of (1) to (7), the direction of the polarization axis of the first optical element and the direction of the polarization axis of the second optical element are different from each other. It's okay.

(9) The light scattering measurement device according to any one of (1) to (8) includes a plurality of detection units including a first detection unit and a second detection unit adjacent to the first detection unit, and The optical device may include a plurality of optical element holders including a first optical element holder corresponding to the first detection section and a second optical element holder corresponding to the second detection section.

(10) The light scattering measuring device according to any one of (1) to (9) meshes with a first gear, rotates with rotation of the first gear, and rotates with the rotation of the first gear. a second gear that is rotatable integrally with the first optical element holder; and a second gear that meshes with the first gear, rotates with rotation of the first gear, and is integral with the second optical element holder. and a third gear that is rotatable.

1 is a perspective view showing a light scattering measuring device according to an embodiment of the present invention. 1 is a diagram schematically showing a planar arrangement of a light scattering measuring device according to an embodiment of the present invention. FIG. 1 is a perspective view showing an optical element holder according to an embodiment of the present invention. FIG. 2 is a side view showing an optical element holder according to an embodiment of the present invention. FIG. 5 is a longitudinal cross-sectional view of FIG. 4 taken along a plane including the rotation axis AR. FIG. 5 is a sectional view of FIG. 4 taken along the line VI-VI. FIG. 7 is a perspective view showing a light scattering measuring device according to a modified example.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

First, an overview of a light scattering measuring device according to an embodiment of the present invention will be described using FIGS. 1 and 2. FIG. 1 is a perspective view showing a light scattering measuring device according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing a planar arrangement of a light scattering measuring device according to an embodiment of the present invention.

As shown in FIGS. 1 and 2, the light scattering detection device 100 includes a light source 1, a sample cell 2, a plurality of detection sections 3, a plurality of optical element holders 4, and an optical element holder support section 5. Be prepared. The light scattering detection device 100 of this embodiment is a multi-angle light scattering measuring device.

A light source 1 generates light L that is irradiated onto a sample. The sample cell 2 is a transparent container that accommodates a sample. Light L from the light source 1 is incident on the sample cell 2 (sample within the sample cell 2). From the sample cell 2 (sample within the sample cell 2), scattered light SL is emitted around the sample cell 2 in a plurality of directions that differ by an angle θ.

Each of the plurality of detection sections 3 detects the scattered light SL corresponding to the detection section 3 among the scattered light SL emitted in the plurality of directions. Therefore, each of the plurality of detection units 3 is provided adjacent to each other at an angle θ with the sample cell 2 as the center on the circumference C1 surrounding the sample cell 2 (FIG. 2). The respective outputs of the plurality of detection units 3 are transmitted to a control device (not shown). Then, the control device calculates the particle size and molecular weight of the substance in the sample based on the angular dependence of the intensity of the scattered light SL detected by each of the plurality of detection units 3. In this embodiment, the sample is assumed to be a liquid sample, but the sample may be a solid sample.

As described later, each of the optical element holders 4 holds a first optical element 401-1 and a second optical element 401-2 (see Figures 3 to 6). Each of the optical element holders 4 is provided between the sample cell 2 and the detector 3 corresponding to the optical element holder 4. That is, each of the optical element holders 4 is provided adjacent to each other at an angle θ on a concentric circumference C2 that surrounds the sample cell 2 and is located inside the circumference C1 (Figure 2). Each of the optical element holders 4 can rotate between a first position in which the first optical element 401-1 is located on the path LP of the scattered light SL from the sample cell 2 toward the detector 3 corresponding to the optical element holder 4, and a second position in which the second optical element 401-2 is located on the path LP (see Figures 3 to 6).

In this way, each of the plurality of optical element holders 4 is rotatable between the first attitude and the second attitude, so that in the light scattering measurement apparatus 100, the first optical element 401-1 It becomes possible to switch between measurement using the optical element 401-2 and measurement using the second optical element 401-2. Note that although FIGS. 1 and 2 show a case where the number of detection units 3 and optical element holders 4 is 11 each, even if the number of detection units 3 and optical element holders 4 is less than this, Or it may be more.

As described above, the optical element holder support section 5 rotatably supports the plurality of optical element holders 4. That is, the optical element holder support portion 5 is formed of a plate material having an annular shape along the circumference C2, and the sample cell 2 is arranged in a hole portion at the center of the annular shape. Note that the shape of the optical element holder support portion 5 is not limited to an annular shape, and may have other shapes.

Below, details of the optical element holder 4 will be explained. First, the entire optical element holder 4 will be described using FIGS. 3 to 5. FIG. 3 is a perspective view showing an optical element holder according to an embodiment of the present invention. FIG. 4 is a side view showing an optical element holder according to an embodiment of the present invention. FIG. 5 is a longitudinal sectional view of FIG. 4 taken along a plane including the rotation axis AR. Note that in FIGS. 3 to 5, only the path LP and a portion of the optical element holder support section 5 are shown.

As shown in FIGS. 3 to 5, the optical element holder 4 includes a main body 40 and a knob 41. As shown in FIGS. The main body 40 includes a lower portion 40a and an upper portion 40b.

The lower portion 40a has a hexagonal prism shape, and the upper portion 40b has a cylindrical shape (Fig. 3). The central axis of the lower portion 40a and the central axis of the upper portion 40b are aligned on the same straight line (Fig. 5), and this straight line is the rotation axis AR of the optical element holder 4. The shape of the lower portion 40a is not limited to a hexagonal prism shape, and may be other shapes such as a cylindrical shape or a hemispherical shape.

The lower end portion of the upper portion 40b is rotatably supported by the optical element holder support portion 5 via spacers 51, 51 (FIG. 5). The spacers 51, 51 each have an annular plate shape with a cylindrical wall rising on the inner periphery thereof. A plurality of holes are formed on the optical element holder support part 5 along the circumference C2, one of the spacers 51, 51 is fitted from the upper side of each hole, and one of the spacers 51, 51 is fitted from the lower side of each hole. The other one is fitted. Further, a cylindrical knob 41 is non-rotatably fitted into the upper end portion of the upper portion 40a (FIGS. 3 and 5). Thereby, the user can rotate the optical element holder 4 around the rotation axis AR by pinching the knob 41. The shape of the knob 41 may be other than cylindrical.

Hereinafter, details of the optical element holder 4 will be explained with further reference to FIG. 6. FIG. 6 is a sectional view of FIG. 4 taken along the line VI-VI.

The lower portion 40a is provided with a first through hole TH1 and a second through hole TH2 that pass through opposing side surfaces (FIG. 6). A first optical element 401-1 is provided at one end of the first through hole TH1, and the other end of the first through hole TH1 is a first opening 402-1. A second optical element 401-2 is provided at one end of the second through hole TH2, and the other end of the second through hole TH2 is a second opening 402-2. Further, the first optical element 401-1 and the first aperture 402-1 face each other. Similarly, the second optical element 401-2 and the second aperture 402-2 face each other.

As a result, the scattered light SL that has entered the first optical element 401-1 passes through the first through hole TH1 and is emitted from the first opening 402-1. The detection unit 3 can detect the scattered light SL that has passed. Similarly, the scattered light SL that has entered the second optical element 401-2 passes through the second through hole TH2 and is emitted from the second opening 402-2. The detection unit 3 can detect the scattered light SL that has passed. Note that the scattered light SL that has entered the first opening 402-1 may pass through the first optical element 401-1 after passing through the first through hole TH1. Furthermore, the scattered light SL that has entered the second opening 402-2 may pass through the second optical element 401-2 after passing through the second through hole TH2.

Furthermore, the lower part 40a is provided with a third through hole TH3 that passes through the opposing side surfaces (FIG. 6). One end of the third through hole TH3 is a third opening 402-3, and the other end of the third through hole TH3 is a fourth opening 402-4. The third opening 402-3 and the fourth opening 402-4 face each other. Further, by rotating the optical element holder 4, the third opening 402-3 and the fourth opening 402-4 can be positioned on the path LP. In this way, by providing a through hole in which no optical element is provided, even when the light scattering measurement apparatus 100 includes the optical element holder 4, the first optical element 401-1 and the second optical element 401 Normal measurements that do not involve -2 can be performed.

Note that the optical element holder 4 may have four or more through holes. That is, the optical element holder 4 may hold three or more optical elements. Further, the optical element holder 4 may have five or more apertures. Furthermore, the arrangement of the first optical element 401-1 and the second optical element 401-2 is not limited to that shown in FIG. 2 may be located adjacent to each other.

In addition, although the openings such as the first opening 402-1 are circular holes (see FIG. 3, etc.), they may be changed to other shapes as long as the function of transmitting light is achieved. . For example, the opening may be a cutout provided at the upper end or lower end of the lower part 40a.

The center line CL1 of the first through hole TH1 is perpendicular to the rotation axis AR and passes through the rotation center CR, which is the intersection of the rotation axis AR and the path LP (FIG. 6). Similarly, the center line CL2 of the second through hole TH2 is orthogonal to the rotation axis AR and passes through the rotation center CR, which is the intersection of the rotation axis AR and the path LP (FIG. 6). Furthermore, the center line CL3 of the third through hole TH3 is perpendicular to the rotation axis AR and passes through the rotation center CR, which is the intersection of the rotation axis AR and the path LP (FIG. 6). Further, the rotation axis AR is located on the path LP and is perpendicular to the path LP (FIGS. 3 to 5).

Thereby, when the optical element holder 4 is rotated, the scattered light SL can pass through the first through hole TH1, the second through hole TH2, and the third through hole TH3. Note that as long as this effect is achieved, the rotation axis AR and the path LP may intersect in a manner other than orthogonal. In addition, as long as this effect is achieved, the rotation axis AR and the center line CL1 of the first through hole TH1, the center line CL2 of the second through hole TH2, or the center line CL3 of the third through hole TH3 are orthogonal to each other. They may intersect in other ways. Further, the rotation axis AR does not need to be located on the path LP, and may intersect with the path LP in a manner other than orthogonal as long as the above effect is achieved.

The first optical element 401-1 and the second optical element 401-2 are each shaped like a plate having two main surfaces. Here, the normal direction of each of the main surfaces of the first optical element 401-1 and the second optical element 401-2 (i.e., the direction of the center line CL1 of the first through hole TH1 and the direction of the center line CL2 of the second through hole TH2) is perpendicular to the rotation axis AR (FIGS. 5-6). In other words, the first optical element 401-1 and the second optical element 401-2 are each provided so as to face the rotation axis AR around the rotation axis AR. That is, the multiple optical elements 401 are not provided on the same plane, and the dead space caused by the optical elements not involved in the measurement can be reduced, so that the optical element holder 4 can be made small. The main surfaces of the first optical element 401-1 and the second optical element 401-2 may be flat or curved.

The first optical element 401-1 and the second optical element 401-2 are each a polarizing element (polarizing plate), as an example here. The direction of the polarization axis of the first optical element 401-1 is parallel to the rotation axis AR, that is, the vertical direction, and the direction of the polarization axis of the second optical element 401-2 is perpendicular to the rotation axis AR. That is, in the horizontal direction. Note that the direction of the polarization axis of the first optical element 41a and the direction of the polarization axis of the second optical element 41b may be arbitrarily set depending on the purpose of measurement. In addition, as the first optical element 401-1 and the second optical element 401-2, in addition to a polarizing element, various optical elements such as an ND filter for adjusting the amount of light, a colored glass filter for adjusting the wavelength, etc. can be selected. For example, one of the first optical element 401-1 and the second optical element 401-2 is a polarizing element, and the other of the first optical element 401-1 and the second optical element 401-2 is an ND filter. Different types of optical elements may be used in combination as appropriate.

By the way, in the optical element holder 4 of this embodiment, the rotation axis AR is located on the path LP, and the first optical element 401-1 and the first opening 402-1 sandwich the rotation axis AR. At the same time, the second optical element 401-2 and the second aperture 402-2 are arranged so as to sandwich the rotation axis AR (FIGS. 5 and 6). With such a configuration, the side surface of the lower part 40a of the optical element holder 4 can be used more effectively, so the optical element holder 4 can be made more compact.

Furthermore, the direction of the center line CL1 of the first through hole TH1, the direction of the center line CL2 of the second through hole TH2, and the direction of the center line CL3 of the third through hole TH2 are all around the rotation center CR. They differ by 60 degrees (Figure 6). That is, the first optical element 401-1, the third aperture 402-3, the second optical element 401-2, the first aperture 402-1, the fourth aperture 402-4, and the third aperture 402-3. The openings 402-2 and 2 are arranged at equal angular intervals all around the rotation axis AR. With such a configuration, the side surface of the lower portion 40a of the optical element holder 4 can be utilized as effectively as possible, so that the optical element holder 4 can be made even more compact.

Note that the present invention is not limited to the above embodiments, and various modifications are possible. Hereinafter, one of the modified examples of the present invention will be explained using FIG. 7. FIG. 7 is a perspective view showing a light scattering measuring device according to a modified example.

In this modification, the light scattering measuring device 100 further includes a large gear 6 and a plurality of small gears 7. The large gear 6 is provided on the optical element holder support 5 , and its plurality of teeth surround the sample cell 2 . Further, the rotation axis of the large gear 6 is parallel to the rotation axis AR of each of the plurality of optical element holders 4.

Each of the plurality of small gears 7 is non-rotatably fitted into the upper end portion of the upper part 40b of the optical element holder instead of the knob 41 in the previously described embodiment, and is rotatable integrally with the optical element holder. It has become. Each of the plurality of small gears 7 meshes with the large gear 6 and rotates as the large gear 6 rotates. In the embodiment described above, each of the plurality of optical element holders 4 was rotated by manually turning the knob 41, but in this modification, the large gear 6 is rotated by the power of a motor etc. All of the plurality of optical element holders 4 can be rotated at once.

DESCRIPTION OF SYMBOLS 100 Optical measuring device, 1 Light source, 2 Sample cell, 3 Detection part, 4 Optical element holder, 5 Optical element holder support part, 6 Large gear, 7 Small gear, 40 Main body, 41 Knob, 401 Optical element, 402 Opening, 51 Spacer, L light, SL scattered light, LP path, AR rotation axis, TH through hole, CR rotation center.

Claims (10)

a light source and
a sample cell that accommodates a sample and receives light from the light source;
a detection unit that detects the emitted light emitted from the sample cell;
A first optical element and a first optical element each having a rotation axis perpendicular to a plane determined by a path of the emitted light heading from the sample cell to the detection unit, and each of which is provided around the rotation axis so as to face the rotation axis. an optical element holder that holds a plurality of optical elements including two optical elements;
an optical element holder support part that supports the optical element holder so as to be rotatable around the rotation axis;
Equipped with
The optical element holder rotates between at least a first attitude in which the first optical element is located on the path and a second attitude in which the second optical element is located on the path. It is possible,
Light scattering measurement device. The optical element holder has a main body and holds the plurality of optical elements on a side surface of the main body,
A plurality of openings are provided on the side surface of the main body, including a first opening opened on the opposite side of the first optical element, and a second opening opened on the opposite side of the second optical element. is provided,
The light scattering measuring device according to claim 1. The rotation axis is located on the path, is sandwiched between the first optical element and the first aperture, and is sandwiched between the second optical element and the second aperture.
The light scattering measuring device according to claim 2. The plurality of optical elements and the plurality of apertures are arranged at equal angular intervals around the rotation axis,
The light scattering measuring device according to claim 3. The optical element holder includes a polygonal section in cross section.
The light scattering measuring device according to claim 4. The plurality of openings include a third opening and a fourth opening that face each other.
The light scattering measuring device according to claim 2. The first optical element and the second optical element are each polarizing elements,
The light scattering measuring device according to claim 1. The direction of the polarization axis of the first optical element and the direction of the polarization axis of the second optical element are different from each other.
8. The light scattering measurement device according to claim 7. a plurality of detection units including a first detection unit and a second detection unit adjacent to the first detection unit;
a plurality of optical element holders including a first optical element holder corresponding to the first detection section and a second optical element holder corresponding to the second detection section;
The light scattering measuring device according to claim 1. a first gear;
a second gear that meshes with the first gear, rotates with rotation of the first gear, and is rotatable integrally with the first optical element holder;
a third gear that meshes with the first gear, rotates with rotation of the first gear, and is rotatable integrally with the second optical element holder;
The light scattering measuring device according to claim 9.

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