JPS6321850B2 - - Google Patents

Description

Detailed Description of the Invention The present invention mainly involves selectively irradiating light of various wavelengths to test liquids according to various measurement items used in automatic analyzers, and measuring the absorbance of the test liquids. The present invention relates to a photometric device that uses multiple wavelengths to measure the reaction state of a test liquid.

Various types of photometric devices have been proposed in the past, and one known example is the device shown in FIG. 1. This device houses a light source 2 in a lamp house 1, and a lens 3 for converting the light from the light source 2 into a parallel beam is provided in the lamp house 1, and the parallel beam from the lens 3 is selected as a beam of a predetermined wavelength. Therefore, an interference filter 4 is installed on the optical path of this parallel light beam. The interference filter holding member 5 that holds the interference filter 4 includes a plurality of types of interference filters 4 for passing light beams of various wavelengths.
will be established. This interference filter holding member 5 has a rotating shaft 6 connected to a driving device 7, and the operation of this driving device 7 rotates the interference filter holding member 5, so that a predetermined interference filter 4 is placed on the optical path of the light beam from the lens 3. can be placed in A reflector 8 with a reflecting mirror attached thereto is provided below the position where this predetermined interference filter 4 is arranged. Since the reflector 8 is rotatably attached to the drive device 9, it can guide the light beam that has passed through the interference filter 4 in a predetermined direction. A test liquid 11 is contained in a reaction tube 10 placed on a turntable (not shown) that moves on the circumference of a circle centered on the rotation axis of the drive device 9, and a plurality of test liquids 11 are set on the turntable. A lens 12 for irradiating the reaction tube 10 with the light beam reflected by the reflector 8 and a light receiving element 13 for measuring the absorbance of the light irradiated into the reaction tube 10 are installed at the photometry positions. With this configuration, this device passes the light emitted from the light source 2 through the lens 3, interference filter 4,
The test liquid 11 contained in the reaction tube 10 is irradiated through the reflector 8 and the lens 12, and the light is received by the light receiving element 13 to measure the absorbance of the test liquid 11 and detect the reaction of the test liquid. This is to check the condition.

By the way, the characteristics of an interference filter that sets the wavelength of light may change at the initial stage of photometry depending on the wavelength to be passed, and the output of the light receiving element may change. FIG. 2 is a diagram showing an example thereof. This example uses an interference filter with a light wavelength of 340 nm, and as is clear from the diagram, the output voltage of the photodetector changes considerably during the first minute from the start of photometry, and after that, the voltage remains almost constant. is maintained.
There are several possible causes for this change in output voltage at the beginning of photometry, one of which is considered to be the influence of temperature. FIG. 3 shows a comparison of changes in the output of the light receiving element and changes in the temperature of the interference filter after the start of photometry. As shown in the figure, while the temperature of the interference filter rises and stabilizes at a constant temperature, the output of the light receiving element changes greatly. When the temperature of the interference filter stabilizes at a constant temperature, the output of the light receiving element also remains almost constant. Stable at output.

In the case of the device shown in Fig. 1 mentioned above, photometry is performed by replacing the interference filters of various wavelengths, and multi-item analysis of the test liquid is performed. When passing,
There is a large change in the output at the beginning of photometry, and especially when changing the interference filter in a short period of time to collect data for various measurement items, this output change has a large effect on the measurement results, making it difficult to obtain accurate measurement results. I couldn't do it.

An object of the present invention is to solve this drawback and provide a photometric device that uses a plurality of wavelengths with little change in the characteristics of an interference filter.

To achieve this purpose, the photometric device using multiple wavelengths of the present invention includes a light source, a plurality of interference filters that selectively pass the light from the light source, and a plurality of interference filters that guide the light from the light source to the interference filters. 1 optical member, a second optical member for guiding light that has passed through a predetermined interference filter among the plurality of interference filters to a predetermined sample, and the first optical member and the second optical member. and means for arranging the predetermined interference filter in an optical path formed by the first optical member, wherein the first optical member constantly guides light from the light source to all of the plurality of interference filters. It is characterized by the following.

Embodiments of the present invention will be described in detail below with reference to FIGS. 4, 5, and 6. FIG. 4 is a diagram showing an example of implementation of the present invention. In FIG. 4, reference numeral 20 denotes a lamp house, which houses a light source 21 therein. One end of a light guide 22 made of an optical fiber is attached to the peripheral wall of the lamp house with the light source 21 in the center, and the other end of the light guide 22 is connected to an interference filter. It is arranged above a plurality of interference filters 24 provided annularly on the holding member 23. The number of light guides 22 is the same as the number of interference filters 24, and one light guide 22 is arranged for each interference filter 24. As a result, the light from the light source 21 is constantly guided to the entire interference filter 24. Interference filter holding member 23
is fixed in a stationary state, and the rotating member 25 is rotatably pivoted to a rotating shaft provided at the lower part of the interference filter holding member. A gear groove is formed on the circumference of the rotating member 25, and a gear 27 attached to the rotating shaft of the motor 26 is engaged with the gear groove on the circumference of the rotating member 25.
6 so that the rotating member 25 can be driven.
One light guide 28 made of a crank fiber provided on the rotating member 25 has one end placed at a position to receive the light that has passed through the interference filter 24 , and the other end located at the center of rotation of the rotating member 25 .
protrude from the bottom of the A prism stand 30 to which the prism 29 is attached is provided below this projecting end, and this prism stand is pivotally connected to the rotating shaft of a motor 31 so that it can be rotationally driven by the motor 31. Lenses 32 and 33 are installed in the optical path of the light beam that passes through the light guide 28 and whose direction is changed by the prism 29,
The test liquid 3 is placed in the optical path of the light beam that has passed through these lenses.
A reaction tube 35 containing 4 is arranged, and this reaction tube 3
A light receiving element 36 is provided behind the reaction vessel 35 in order to receive the light that has passed through the reaction vessel 35, and the light received by the light receiving element 36 is photoelectrically converted and processed as an electrical signal. The reaction tube 35 is placed on a turntable (not shown), and this turntable is located on the circumference of a circle centered on the rotation axis of the prism 29. A plurality of photometric positions are set on the turntable, lenses 32 and 33 and a light receiving element 36 are provided for each of these photometric positions, and a prism is rotated via a motor 31 to select a predetermined one of these photometric positions. The rotation of the motor 31, which guides the light beam to the photometry position, is controlled by a control device (not shown). Also, a motor 26 is used to rotate the rotating member 25 and stop the incident end of the light guide 28 below a predetermined interference filter 24.
6 is also controlled by a control device (not shown).

With this configuration, this device passes the light from the light source 21 through the light guide 22 to each interference filter 24.
The light that has passed through a predetermined interference filter 24 is guided to a prism 29 by a light guide 28,
The direction of the light flux is changed from this prism 29 in the direction of a predetermined photometry position, and the light flux is irradiated via lenses 32 and 33 to a reaction tube 35 containing a test liquid 34, and the light that has passed through this reaction tube 35 is received. The element 36 receives light, photoelectrically converts it, processes it, measures the absorbance of the test liquid, and can investigate the reaction state of the test liquid.

Since this device constantly irradiates all of the interference filters 24 with light from a light source 21 via a light guide 22, stable data can be obtained without changing the characteristics of the interference filters used for photometry.

In FIG. 5, a lens 38 and a prism 39 are provided in place of the light guide 22 in the embodiment shown in FIG.
Prisms 40 and 41 instead of light guide 22
The rest of the structure was the same as that of the embodiment shown in FIG. With this photometric device, the same effects as in the embodiment shown in FIG. 4 can be obtained.

FIG. 6 is a diagram showing still another embodiment of the photometric device of the present invention, in which light from a light source 21 is passed through a lens 43 and a reflecting mirror 44 to an interference filter 2.
4, a prism 29 is provided directly below a predetermined interference filter 24, and the interference filter holding member 23
is attached to the shaft of a motor 26, and a predetermined interference filter 24 can be rotated to a predetermined position above the prism 29 and stopped by driving the motor 26 by a control device (not shown). In addition, the lamp house 20 and the reflecting mirror 44
The filter 24 can be constantly irradiated with light from the light source 21 by being integrally attached to the interference filter holding member 23 and configured to be able to rotate together with the interference filter holding member 23.

In the photometry device of the present invention configured in this way, which uses multiple wavelengths, the interference filter is constantly irradiated with light, so even when changing the interference filter to measure various items, the interference filter does not detect the change in characteristics at the start of photometry. This is a photometric device that can obtain stable and accurate data because it does not cause any noise.

[Brief explanation of drawings]

Fig. 1 is a diagram schematically showing the configuration of a conventional photometry device, Fig. 2 is a characteristic diagram showing changes in the output of the photodetector at the start of photometry, and Fig. 3 is a diagram showing the changes in the output of the photodetector at the start of photometry. A characteristic diagram showing a comparison between changes in output and changes in temperature of the interference filter, FIG. 4 is a diagram showing the configuration of an embodiment of the photometric device of the present invention, and FIG. 5 is a diagram showing the configuration of an embodiment of the photometric device of the present invention. FIG. 6 is a diagram showing the configuration of another embodiment of the photometric device of the present invention. DESCRIPTION OF SYMBOLS 1... Lamp house, 2... Light source, 3... Lens, 4... Interference filter, 5... Interference filter holding member, 6... Rotation shaft, 7... Drive device, 8...
Reflector, 9... Drive device, 10... Reaction tube, 11
... Test liquid, 12 ... Lens, 13 ... Light receiving element, 20 ... Lamp house, 21 ... Light source, 22
... Light guide, 23 ... Interference filter holding member, 24 ... Interference filter, 25 ... Rotating member,
26... Motor, 27... Gear, 28... Light guide, 29... Prism, 30... Prism stand, 31... Motor, 32, 33... Lens, 3
4... Test liquid, 35... Reaction tube, 36... Light receiving element, 38... Lens, 39, 40, 41... Prism, 43... Lens, 44... Reflecting mirror.

Claims (1)

[Claims] 1. A light source, a plurality of interference filters that selectively pass the light from the light source, a first optical member for guiding the light from the light source to the interference filters, and a predetermined member among the plurality of interference filters. a second optical member for guiding the light that has passed through the interference filter to a predetermined sample, and the predetermined interference filter is arranged in an optical path formed by the first optical member and the second optical member. A photometer using a plurality of wavelengths, characterized in that the first optical member always guides light from the light source to all of the plurality of interference filters.