JPS5991402A - Optical switch for spectrochemical analysis - Google Patents

Abstract

PURPOSE:To assure the secure arrival of monochromatic light having a prescribed wavelength at a prescribed photoelectric transducer in a photodiode array by providing an optical switch stator wherein plural optical exit end faces are disposed near the diametral line of the circumference in parallel with a light dispersion plane by a spectroscope. CONSTITUTION:An optical switch rotor 22 is disposed rotatably around the central axis thereof by a driving device with the central axis positioned on the extension line of the central axis O of an optical switch stator 21, and is constituted of a mirror M1 disposed so as to intersect the light emitted from the end faces 7a, 7b, 7c, 7d of the bundles fiber at the stator 21 with the central axis and a mirror M2 reflecting the light reflected by the M1 toward a grating G, on the circumference corresponding to the virtual circumference C on the end face of the stator 21. The deviation of the optical axis in a horizontal direction owing to a deviation of the mirror M1 in its stop position is negligible and therefore the respective monochromatic light dispersed by the grating G in the horizontal direction are conducted to the prescribed photoelectric transducers in a photodiode array PDA and the error in wavelength is negligible.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an optical switch for spectroscopic analysis, and more specifically, to an optical switch for spectroscopic analysis that can be applied to an automatic chemical analyzer.
Regarding an optical switch for analysis.

[Technical background of the invention and its problems]

Conventionally, there are so-called multi-channel automatic chemical analyzers that can simultaneously analyze multiple items on the same sample. This multi-channel automatic chemical analyzer # has a measurement system as shown in FIG. The measurement system is constructed as follows. That is, the light emitted from the light source 1 is focused and incident on one end of the bundle fiber 3 by the condenser lens system 2. The light that enters and is transmitted through the bundle fiber 3 is branched into six branches from the other end to four photometric cells 4a.

4h, 4c, and 4d are all irradiated. Photometric cell 4a
.

The light that has passed through /Jb, /JC,4d enters one end of the bundle fiber 7, which is branched into four trees, and is guided to the optical switch 8. The optical switch 8 selects one of the four types of light and guides it to the multi-wavelength spectrophotometer in a time-sharing manner through the lens system 9.The multi-wavelength spectrophotometer 10 has a slit S1 grating. G1 photodiode array pD
The absorbance of the test sample in the photometric cell 4°5.6 is measured with Af.

The optical switch 8 in the measurement system is, for example, as shown in FIG.
It is constructed as shown in α) and <h>.

In other words, as shown in FIG. 2(h), the four branched end faces of the bundle fiber 7 are arranged in the same direction so that the central angle between the adjacent end faces and the center of the circle is a right angle. Disc-shaped optical switch stator 1 arranged on the circumference
6, and two mirrors M, which are disposed opposite to the optical switch stator 16, and which take out one optical beam emitted from the end face of the bundle fiber 7 in a fixed direction.
The optical switch rotor 17 is equipped with an optical switch rotor 17 that is rotatable around a central axis and has an optical fiber M2 inside thereof, and the optical beam emitted from a specific end face of the bundle fiber 7 is split into four by rotating the original switch rotor 17. It is configured so that it can be selected.

However, in the original switch 8 shown in FIG. 2 (α) t (h) in the measurement system shown in No. 14 above, in order to keep the measurement error within a predetermined value, it is necessary to fully expose the end face of the bundle fiber 7. Accuracy of hole drilling,
The stopping accuracy of the optical switch rotor 17 is very strict.
Difficult to realize in practice. Therefore, this generally results in a wavelength error in the multi-wavelength spectrophotometer 10, resulting in a measurement error.

This is because the photodiode array pDA and the grating G are arranged horizontally, and the grating G
When each of the monochromatic lights horizontally dispersed by n reaches the photodiode array pDA, as shown in FIG. When guiding the emitted light to grating G, mirror M, ,
If the stop position of M2 is not correctly aligned with the end surface, the optical axis emitted from the end surface will be shifted horizontally, as shown by the broken line A and the dashed line B in FIG. Since the light is no longer incident on the local electric conversion element in the photodiode array PDA, an apparent wavelength shift occurs.

[Purpose of the invention]

This invention was made in view of the above circumstances, and even if there is some error in the stopping position of the optical switch rotor in the nine switches, monochromatic light of a predetermined wavelength can be transmitted to a predetermined photoelectron in the seven photodiode array. The object of the present invention is to provide an optical switch for spectroscopic analysis that accurately reaches a conversion element.

[Summary of the invention]

To achieve the above object, the present invention provides an optical switch stator in which the light emitting end surfaces of a plurality of two light means for transmitting a plurality of light beams are arranged on the same circumference; a first mirror, which is displaced on a corresponding circumference, and which reflects the light emitted from the light emitting end surface so as to cross the central axis passing through the center of the circumference; and a mirror disposed on the central axis. At the same time, the light reflected by the first mirror is
and an optical switch rotor having a second mirror that guides a spectroscope to disperse monochromatic light toward a photodiode array. an optical switch stator arranged near the diameter line of the circumference parallel to the original dispersion plane,
It is characterized by having the following.

[Embodiments of the invention]

FIG. 4 is an explanatory diagram showing one embodiment of the present invention.

Optical switch 20 for spectroscopic analysis which is an embodiment of the present invention
Fis optical switch stator 21 and optical switch ROMATA 22
and has.

For example, the original switch stator 21t is disposed facing the optical switch rotor 22, and the bundle fiber 7 is connected to the end face portion of the optical switch rotor 22, which has a substantially disk shape.
End faces 7a, 7h, 7c of branched fibers branched into books
, 7d and 7d are arranged in the manner described below to form the end faces 7α, 7.
The structure 2' is such that light is emitted from ports b, 7c, and 7d. And the end faces 7α, 7h, 7 of the branch fiber
c and 7d are photodiode arrays formed by arranging photoelectric conversion elements in the horizontal direction 1) When the grating G is horizontally dispersing instantaneous light on DA, the central axis 1'J (i) is the horizontal optical switch stator 21 It is arranged so that the following conditions are satisfied on the disk-shaped end surface of the disk. That is,
Position yourself in the L position.

■ The rudder must be close to the horizontal diameter.

Here, the vicinity of the horizontal diameter line refers to the vicinity of the horizontal diameter line.
This is a region where the distance between the radius line passing through the end faces of

■ The four end faces shall be divided into two sets, each consisting of one set of two end faces, and the end face length t'L of each set shall be arranged across the horizontal diameter line. It is.

The optical switch rotor 22 has the same structure as the conventional device, and will be explained in more detail as follows.

That is, the original switch rotor 22 has its central axis located on an extension of the central axis O of the optical switch stator 21, and is rotatably arranged around the center 1111 by a drive device (not shown). , the light emitted from the end faces 7α, 7h, 7c, and 7d of the bundle fibers in the switch stator 21 intersects the central axis on a circumference corresponding to the virtual circumference C on the end face portion of the switch stator 21. A mirror M1 arranged 7' as shown in FIG. ILru.

As described above, when the optical switch 20 for spectroscopic analysis is configured, the original switch rotor is arranged so that the mirror M faces each of the four bundle fiber end faces 7α, 7h, 7c, and 7cl in the optical switch stator 21. 22 When the mirror M1 is stopped, even if the stop position of mirror M1 is slightly tilted, it still satisfies the condition of s ml, so the mirror M1 is moved in the horizontal direction of the optical axis due to the stop position. Since the waveform is so small that it can be ignored, each monochromatic light beam dispersed in the horizontal direction by the grating G is guided to a predetermined photoelectric conversion element in the photodiode array PDA, and the wavelength error can be ignored. .

Additionally, since the bundle fiber end faces 7a, 76.7c, and 7t satisfy the condition (2) above, the original switch rotor 2
By rotating the bundle fiber twice, the bundle fiber end face 7C
The light emitted from any of the gratings 1, 7b, 7c, and 7d can be guided to the grating G. By arranging the fiber end face 7''t7l)e7't7d in this way, the accuracy of the stopping position of the original switch rotor 22 becomes easier compared to the arrangement shown in FIG. It is advantageous.

Although the embodiments of this invention have been described in detail above, this invention is not limited to the embodiments described in @, and can be implemented with appropriate modifications within the scope of the gist of the invention. Needless to say.

In the embodiment, the end face 7α* of the bundle fiber
7b, 7c, and 7ct were found to satisfy the conditions of (1) and (2) above. In this invention, the arrangement of the end faces 7α, 76.7c, and 7d of the bundle fiber is determined by the original dispersion surface that disperses the monochromatic light from Krechie G to the photodiode array PDA.

For example, when the photoelectric conversion elements in the photodiode array PDA are arranged vertically and the grating G disperses monochromatic light vertically toward the photodiode array PDA, the conditions of The end faces 7a, 76.7c, and 7d are divided into two sets of two end faces, and the end faces in each set are t'L and tl-.
are arranged so as to face each other across the vertical diameter line, and are n.

〔Effect of the invention〕

According to this invention, even if there is some error in the stop position IN of the optical switch rotor, monochromatic light of a predetermined wavelength can accurately reach a predetermined photoelectric conversion element in an all-photodiode array, and the configuration is simple. A spectrometer switch can be provided.

When a spectroscopic analyzer is configured using the spectroscopic analyzer switch according to the present invention, it is possible to perform reproducible and accurate spectroscopic analysis with few wavelength errors.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram showing the foot measurement system in a multi-channel automatic chemical analyzer, Figure 2 (a) is an explanatory diagram showing the main switch in the foot measurement system, and Figure 2 (b) is an explanatory diagram showing the optical switch. (9) is an explanatory diagram showing the disc-shaped end face of the original switch stator in the original switch, FIG. FIG. 4(b) is an explanatory view showing a disk-shaped end face portion of an original switch stator in an original switch which is an embodiment of the invention, and FIG. 4(b) is an explanatory view showing an optical switch which is an embodiment of the invention. 7a, 7b, 7c, 7d --- Bundle fiber end face, 20... Optical switch, 21... Optical switch stator, 22... Optical switch rotor, Mi, M2...
・Mirror, C...Circumference, 0...Center axis.

Claims (3)

[Claims] (1) Light-emitting end face ligation of a plurality of light transmission means for transmitting a plurality of light beams - original switch stators arranged on a circumference, fully displaced on a circumference corresponding to the circumference, and
a first mirror that reflects the light emitted from the light emitting end surface so as to intersect with the central axis passing through the center of the circumference; An optical switch for spectroscopic analysis includes an optical switch rotor having a second mirror that guides the reflected light to a spectrometer that disperses the reflected light into monochromatic light toward a photodiode array. 1. An optical switch for spectroscopic analysis, comprising an optical switch stator arranged near the diameter line of the circumference parallel to the light dispersion plane of the device. (2) The optical switch for spectroscopic analysis according to claim 1, wherein the vicinity of the diameter line is an area within a range of 45° from the center of the circumference with respect to the diameter side. . (3) The optical switch for spectroscopic analysis according to claim 1 or 2, wherein the optical transmission means is an original fiber.