JPS61225636A - Flow-through optical cell - Google Patents

Abstract

PURPOSE:To obtain a measuring light beam enough to operate a detector, by providing a lens section at the front window of a sample reservoir into which light is made incident to converge light into the sample reservoir. CONSTITUTION:An inlet/outlet path 3 of a fluid sample 6 is provided on the both end sides of a sample reservoir 1 of a flow-through optical cell C and a lens section 4 is formed at the front window of the sample reservoir 1 while a lens section 5 at the rear window thereof 1. The optical cell C shall be located at the rear of an outlet slit S of a spectroscope with optical axes made to align. Then, a monochromatic light emitted from the outlet slit S of the spectroscope enters the sample reservoir 1 being focused to the center thereof 1 with the lens section 4 of the optical cell C and after absorbed by the sample 6, it made a parallel luminous flux with the lens section 5 to be incident into a photoelectric detector D for photometry. This can increase the quantity of light transmitted through the sample 6 to obtain a measuring light beam sufficient for effective operation of the detector D.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention wavelength-disperses light emitted from a light source using a spectrometer, and irradiates a sample placed immediately after the exit slit with monochromatic light taken out from an exit slit. The present invention relates to a flow-through optical cell that is used for sample delivery in a spectrophotometer or the like that performs analysis by measuring the light transmitted by a detector using a detector, and is a type of flow-through optical cell in which a fluid sample is sequentially introduced.

The present invention provides that when monochromatic light is transmitted through a sample reservoir of an optical cell,
This is a flow-through optical cell in which a lens portion is provided on the front window of the sample reservoir so that the luminous flux increases toward the sample reservoir, increasing the amount of light that completely passes through the sample.

Prior Art Conventionally, in flow-through optical cells, the cell capacity has been reduced for reasons such as saving on collected samples.

In such a miniaturized optical cell, as shown in FIG. 3, the cross-sectional area of the sample reservoir 1a in the optical cell C1 through which the monochromatic light emitted from the exit slit S passes becomes smaller.
This became a kind of aperture, and it was not possible to provide the detector with a sufficient amount of light to be effective for measurement.

Problems to be Solved by the Invention The present invention has been devised in view of the disadvantages of the conventional flow-through optical cell. It provides a through optical cell.

Means for Solving the Problems In the present invention, a lens part for converging light is formed in the window part of the sample reservoir into which the light enters, and the light rays emitted from the slit efficiently enter the sample reservoir by the lens part. The solution to this problem was a flow-through optical cell that allows light to pass through the sample.

When the monochromatic light emitted from the exit slit of the action spectrometer enters the lens section of the window section of the optical cell, the monochromatic light is focused by the lens section and becomes a narrow beam of light that enters the sample reservoir and passes through the sample. Therefore, even if the cross-sectional area of the sample reservoir is small, the monochromatic light beam transmitted through the sample is not blocked by the wall of the sample reservoir and enters the detector in a large amount of light for measurement.

Example An embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2.

In Fig. 1, C is a flow-through optical cell, 1 is a sample reservoir that is coaxial with the optical axis 2 and extends long in the optical axis direction;
Fluid sample inlet/outlet passages 3, 3 are provided on both sides of the tube. Reference numeral 4 denotes a lens portion formed on the front window of the sample reservoir 1, and numeral 5 represents a lens portion formed on the rear window of the sample reservoir 1. The lens portion must be located at least on the front window. The optical cell is placed behind the exit slit S of the spectrometer M with its optical axis aligned. In Fig. 2, L is a light source, and the light beam from this light source enters the entrance slit S1 of the spectrometer M via the light source mirror m, is reflected by the mirror m1, is wavelength-dispersed by the diffraction grating G, and exits from the exit slit S. Emitted as monochromatic light. This monochromatic light enters the sample reservoir 1 in a state where it is focused approximately at the center of the sample reservoir 1 by the lens section 4 of the optical cell C, is absorbed by the sample 6, and then becomes a parallel light beam by the lens section 5 and photoelectrically The light enters the detector and is measured.

Normally, the solid angle ST of the effective light beam entering the sample reservoir 1 as seen from the output point S is, where Sc is the cross-sectional area of the sample chamber and j is the distance between the output point S and the sample chamber 1. The angle S T = S c /z. In the conventional example shown in Fig. 3, SC-1mm
, ! = 20mm, 5T = 0.058tr
becomes. However, in the case of the above embodiment, when the image of the exit slit S is created at the center of the sample reservoir 1 by the lens section 3, the solid angle is ST from 0.07 to 0.20 st
It has been experimentally found that it can be made as large as r.

The reason why the rear end of the cell is also shaped like a lens is that the light flux that converges near the center of the cell will diverge after that due to the action of the lens on the front end side, so the light flux is made so that it does not go beyond the light-receiving area of the light-receiving element. This is for convergence.

Effects The present invention is as described above, and since the lens section is provided in the front window of the sample reservoir, the incident light beam is focused into the sample reservoir by the lens section, and the amount of light that passes through the sample is increased. Therefore, it can be used as a flow-through optical cell to obtain sufficient measurement light for the detector to operate effectively.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of an embodiment of the present invention, FIG. 2 is a reduced simplified side view of a spectrophotometer using the same, and FIG. 3 is a side sectional view of a conventional example. In the figure, C... 70-Through optical cell, 1... Sample reservoir, 4... Lens section. Iki Closet Encyclopedia ↓ Spoon Spring No. 15A

Claims (1)

[Claims] A flow-through optical cell characterized in that a front window portion of a sample reservoir into which light enters is provided with a lens portion for converging light into the sample reservoir.