JPH08145794A - Spectroscope - Google Patents

Abstract

PURPOSE: To enlarge freedom of selection of vessel material and reduce weight of a whole body in a spectroscope, by preventing a direct influence from being exerted upon optical arrangement relationship of optical elements fitted inside the vessel even when the vessel for housing the optical elements is deformed due to temperature and pressure difference. CONSTITUTION: The spectroscope is composed of an optical bench 2 wherein various kinds of optical elements such as a light dispersion element 6 and slits 8, 10, and a vessel 4 for housing this optical bench 2. The optical bench 2 is provided with an element fitting part 2a to which optical elements 6-10 are fitted and a vessel fixing part. 2b to be fixed to the vessel 4, and is formed so that the element fitting part. 2a has a cantilever structure for the vessel fixing part 2b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spectroscope for splitting light from a light source such as a sample into spectra for each wavelength component, such as optical emission spectroscopy and optical absorption spectroscopy. The present invention relates to a structure for mounting a device.

[0002]

2. Description of the Related Art Generally, this type of spectroscope is constructed by combining a wavelength dispersion element such as a diffraction grating and a prism, and various optical elements such as a condenser lens and a slit.

In the conventional device, each of these optical elements is mounted in a container as shown in FIG.

That is, the spectroscope shown in FIG. 3 is used for an emission spectroscopic analysis apparatus, and is provided with a box-shaped vacuum container a, and a diffraction grating, a prism, etc. are provided at the bottom of the container a. Wavelength dispersion element b, entrance slit c, exit slit
d is fixed, and a condenser lens e is attached to the outer peripheral wall of the container a.

Then, after the light obtained by emitting the light from the sample g is condensed by the condenser lens e, it is separated into a spectrum of each wavelength component by the wavelength dispersion element b through the entrance slit c, and each spectrum light is dispersed. The light is detected by a photodetector such as a photomultiplier tube (not shown) through the exit slit d.

Although not shown in FIG. 3, after mounting the optical elements b to e, a lid is attached to the upper part of the container a to keep the inside of the container a airtight.

[0007]

By the way, in the spectroscope, in order to secure the required analysis accuracy, it is necessary that the optical arrangement of the optical elements b to d is always maintained stably. It is necessary to eliminate the occurrence of misalignment of the optical axis as much as possible.

However, in the conventional case, since the optical elements b to d are directly attached to the bottom portion of the container a, the container a is subject to thermal strain due to the temperature change of the atmosphere, and the container a for vacuum is not When the container a is distorted due to the pressure difference between the inside and the outside of the container a, the influence thereof directly changes the arrangement relationship of the optical elements b to d, which is a factor of lowering the analysis accuracy.

Therefore, conventionally, a material having a small thermal expansion coefficient is selected so that the strain of the container a becomes small with respect to a temperature change or a pressure change, or the wall thickness is set to be large. However, such measures not only limit the materials used for the container a but also increase the weight.

The present invention has been made in order to solve the above-mentioned problems, and the optical elements of the optical element mounted inside the container are distorted even when the container for accommodating the optical element is distorted due to temperature or pressure difference. It is an object of the present invention to provide a spectroscope that has a large degree of freedom in selecting a material for a container and that can reduce the overall weight without directly affecting the physical arrangement relationship.

[0011]

The present invention adopts the following constitution in order to solve the above-mentioned problems.

That is, the spectroscope of the present invention comprises an optical bench on which various optical elements such as a light dispersion element and a slit are mounted, and a container in which the optical bench is housed. It has an element mounting portion to be mounted and a container fixing portion fixed to the container, and the element mounting portion is formed to have a cantilever structure with respect to the container fixing portion.

[0013]

In the above structure, since the container fixing portion constituting the optical bench is fixed to the container and the element mounting portion is formed in a cantilever structure with respect to the container fixing portion, the element mounting portion is fixed to the container. The end opposite to the part is a free end.

Therefore, even if the container is subjected to thermal strain due to the temperature change of the atmosphere, or if the container for vacuum is distorted due to the pressure difference between the inside and the outside, the element mounting portion of the optical bench will not Not affected.

Therefore, the optical arrangement of the optical elements attached to the element attaching portion is always maintained stable.

[0016]

1 is an exploded perspective view of a spectroscope according to an embodiment of the present invention.

The spectroscope 1 of this embodiment is used in an emission spectroscopic analysis apparatus, and includes an optical bench 2 for mounting optical elements, and a container that serves as both a housing for the optical bench 2 and a vacuum holding. It consists of two members.

The optical bench 2 is an integrally molded product made of iron casting or the like having a small thermal expansion coefficient, and has a substantially trapezoidal plate-shaped element mounting portion 2a and a vertically long flat plate arranged orthogonal to the element mounting portion 2a. The container mounting portion 2b is shaped like a cantilever with respect to the container fixing portion 2b. That is, in the element mounting portion 2a, on the left and right opposing sides, the long side (the right side in FIG. 1) is connected to the container fixing portion 2b side, and the short side (the left side in FIG. 1) is free. It is the end.

A hole 2c for reducing the weight of the optical bench 2 is formed in the center of the element mounting portion 2a, and the light dispersion element 6 and the entrance slit 8 are provided around the hole 2c. While the optical elements such as the outlet slit 10 are attached, the container fixing portion 2b is provided with a mounting hole 2d such as a bolt in the outer edge portion thereof, and further, the holder 14 of the condenser lens 12 is attached to the upper portion thereof. There is.

On the other hand, the container 4 is an integrally molded product made of relatively thin stainless steel or the like, and is set so as not to be deformed due to a pressure difference between the inside and outside thereof, and one end thereof is opened. It has a box-shaped container body 4a and a flange portion 4b protruding outward on the open end side of the container body 4a, and the flange portion 4b is provided with a mounting hole 4c such as a bolt. .

The element mounting portion 2a of the optical bench 2 is housed and arranged inside the container body 4a, and the flange portion 4b is joined to the outer edge portion of the container mounting portion 2b so that the mounting holes 2d and 4c are formed. Use a bolt (not shown) that has been
4 is fixed.

In the above structure, the container fixing part 2b constituting the optical bench 2 is integrally fixed to the flange part 4b of the container 4, but the element mounting part 2a is cantilevered with respect to the container fixing part 2b. Because of the structure, the element mounting part 2b
The end opposite to the container fixing portion 2b is a free end.

Therefore, the container 4 is affected by the temperature change of the atmosphere.
Is subject to thermal strain, and even if the container 4 is distorted due to the pressure difference between the inside and the outside because the container 4 is evacuated, the element mounting portion 2a of the optical bench 2 is almost free from the influence of the distortion of the container 4. I do not receive it.

Therefore, the optical arrangements of the optical elements 6 to 10 attached to the element attaching portion 2a are always maintained stable.

In the above embodiment, the optical bench 6 has a so-called vertical structure in which the optical elements 6 to 10 are attached to one side surface of the element mounting portion 2a. This is convenient because the influence of distortion due to the weight of the portion 2a is reduced.

However, as shown in FIG.
It is also possible to adopt a so-called horizontal structure in which the optical elements 6 to 10 are attached to the upper surface of the element mounting portion 2a. In this horizontal structure, in order to eliminate the influence of strain due to the weight of the element mounting portion 2a, it is preferable that the element mounting portion 2b has a shape in which the thickness increases from the free end side to the container fixing portion 2b side.

In this embodiment, the container 4 serves both to house the optical bench 2 and to hold the vacuum, but the present invention can be applied to a container open to the atmosphere. Furthermore, in this example, the spectroscope used for the emission spectroscopic analysis device has been described, but the spectroscope used is not limited to this, and may be a spectroscope used for optical absorption spectroscopic analysis and the like. The present invention can be widely applied to any spectroscope that disperses light from a light source into a spectrum for each wavelength component.

[0028]

According to the present invention, the following effects can be obtained.

(1) Even if the container containing the optical element is distorted due to temperature or pressure difference, it does not directly affect the optical arrangement of the optical element mounted inside the container.

Therefore, the optical arrangement of each optical element is always maintained stably.

(2) Since the optical bench on which the optical element is mounted and the container for housing the optical bench are constructed separately, the degree of freedom in selecting the material of the container is increased, and the thickness of the container is extremely large. Since it is not necessary to set it to a large value, the weight of the entire spectroscope can be reduced.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a spectroscope according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a modified example of the spectroscope of the present invention.

FIG. 3 is a perspective view of a conventional spectroscope.

[Explanation of symbols]

1 ... Spectrometer, 2 ... Optical bench, 2a ... Element mounting part, 2b ...
Container fixing part, 4 ... Container, 4a ... Container body part, 4b ... Flange part, 6-10 ... Optical element.

Claims (1)

[Claims] 1. An optical bench including various optical elements such as a light dispersion element and a slit, and a container accommodating the optical bench, wherein the optical bench includes an element mounting portion to which the optical element is mounted. A spectroscope having a container fixing part fixed to the container, wherein the element mounting part is formed to have a cantilever structure with respect to the container fixing part.