JPH02147938A - Light source apparatus for measuring density - Google Patents

Abstract

PURPOSE:To measure a desired item at a desired channel by holding an optical filter adapted to transmit light with a specified wavelength alone selectively detachably at a fiber connection while a quantity of light adjusting means is provided. CONSTITUTION:A plug holder 13 houses an interference filter 20 which transmits light with a wavelength selected previously corresponding to measuring items of a surface 6 to be measured. A recess is formed at the lower end of a second holder 13b in such a manner as to allow the housing of a light shielding ring 30 and the light shielding ring 30 is supported at a peripheral part of the lower end face with a first holder section 13a being housed in the recess to be held at a first connection 10. The quantity of light entering a second fiber section 5B is adjusted by the size of an opening 30a. Both the holders are turned to relese the screwing thereby facilitating the exchange of the interference filter 20 and the light shielding ring 30.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a light source device for density measurement that is used in a density measurement device and irradiates light onto a surface to be measured.
The present invention relates to a light source device for concentration measurement that guides light emitted from one light source through a plurality of optical fibers and illuminates a plurality of surfaces to be measured.

(Prior Art) Qualitative or quantitative analysis of specific chemical components in a test liquid is a commonly performed operation in various industrial fields. In particular, quantitative analysis of chemical components or formed components in biological body fluids such as blood and urine is extremely important in the field of clinical biochemistry.

In recent years, dry type chemical analysis slides have been developed that can quantitatively analyze specific chemical components or formed components contained in a test liquid by simply applying small droplets of the test liquid ( Special Publication No. 53-21677, Japanese Patent Publication No. 55
-18435B etc.) has been put into practical use. Using these chemical analysis slides allows for easier and faster analysis of test liquids than conventional wet analysis methods.
Its use is particularly preferred in medical institutions, laboratories, etc. where it is necessary to analyze a large number of test liquids.

In order to analyze the chemical components in a test liquid using such a chemical analysis slide, the test liquid is placed on the chemical analysis slide in a measured amount and then placed in an incubator for a predetermined period of time. It is kept at constant temperature (incubation) to cause a color reaction (pigment formation reaction), and then a measurement irradiation light containing a wavelength selected in advance by the combination of the components in the test liquid and the reagent contained in the reagent layer of the chemical analysis slide is applied. is irradiated onto this chemical analysis slide and its reflected optical density y 4-
q3 is determined, thereby performing a quantitative analysis of the above chemical components, etc. Furthermore, an apparatus has been proposed in which a long tape-shaped test film containing a reagent is housed in place of the slide described above, and the test film is sequentially pulled out to perform spotting, incubation, and measurement in order (for example, in the US patent Specification 3.52G, 480)
.

In the above-mentioned biochemical analyzer, the concentration of the test object such as the chemical analysis slide or long test film is measured by a concentration measuring device. A density measurement light source device is used to irradiate a surface to be measured with density measurement light. As the above-mentioned light source device, one is known that includes a light source and an optical fiber that transmits light emitted from the light source to a surface to be measured. When light is irradiated using an optical fiber in this manner, the light source and the surface to be measured can be placed at any desired location, which has the advantage of increasing the degree of freedom in designing the device.

Furthermore, by bringing the input end faces of a plurality of optical fibers close to one light source, the exit end faces of these optical fibers can be brought close to the plurality of surfaces to be measured, thereby reducing the irradiation of light onto the plurality of surfaces to be measured. Can be done at the same time.

By the way, the light source of the above-mentioned light source device is usually a xenon flash lamp or a tungsten lamp that emits light over a relatively wide wavelength range. On the other hand, the effective wavelength for measurement differs depending on the component of the object to be measured. That is, when the concentration of a certain measurement component changes, the wavelength of light at which the amount of light such as reflected light from the surface to be measured changes most significantly differs for each measurement component. For example, for glucose measurements, 51
Light around 0 nm is most effective. Therefore, if the light source device selectively irradiates only the light of the above-mentioned specific wavelength onto the surface to be measured,
The concentration of the component to be measured can be measured most effectively.

In order to selectively irradiate only the light of a specific wavelength onto the surface to be measured, an optical filter such as an interference filter that selectively passes only the light of the above-mentioned specific wavelength should be placed on the optical path of the irradiated light. is possible.

(Problem to be Solved by the Invention) By the way, in the above-mentioned light source device equipped with a plurality of optical fibers, it is desirable to be able to measure any measurement component (item) at each light irradiation position (channel) of each optical fiber. There is a request. When changing the IIFJ constant items for each channel, it is necessary to change the above-mentioned optical filter provided on the optical path of the light each time to one that transmits only light of a wavelength suitable for the item to be measured. However, the amount of light emitted from a light source differs depending on the wavelength, and if the type of optical filter used is changed, the amount of light that passes through the filter and enters the surface to be measured changes. - For boat fishing, in order to offset the fluctuations in the amount of light mentioned above and perform stable concentration measurements, it is necessary to adjust the amplification factor in advance when amplifying the signal obtained by detecting the reflected light in response to the fluctuations in the amount of light. It is conceivable to change the amplification factor, but in this case, the amplification factor would be determined for each channel, and it would not be possible to meet the request to measure an arbitrary item by changing the wavelength of light appropriately for each channel. It is also possible to place the end fiber that uses light at a wavelength with relatively low light intensity closer to the center of the light source where the light output is relatively higher than other optical fibers, but in this case, the wavelength that can be used in each channel may be is decided.

The present invention was made in view of the above problems, and makes it possible to accurately measure any item in each channel in a light source device that irradiates light onto multiple surfaces to be measured using multiple optical fibers. The object of the present invention is to provide a light source device for concentration measurement.

(Means and Effects for Solving the Problems) The light source device for concentration measurement of the present invention is a light source device consisting of the above-mentioned light source and a plurality of optical fibers, each optical fiber having a first and a second fiber part, and the fiber connecting part inserts and takes out an optical filter that selectively transmits only light of a specific wavelength between the first fiber part and the second fiber part. and the fiber connection part limits the passage of the light so that the amount of light passing through the fiber connection part is approximately constant regardless of the wavelength of the light transmitted by the optical filter. The present invention is characterized in that an adjusting means is provided at least when the optical filter is inserted.

If the amount of light is adjusted in this way by the light jl On the means side, the signal amplification factor can be kept constant for each channel, and any item can be measured in each channel. Specifically, the light amount adjusting means adjusts the amount of light by restricting the passage of light, so that the amount of light emitted from each optical fiber is adjusted to the light of the wavelength with the least amount of light. Therefore, the amplification factor on the detection means side may be set in accordance with the wavelength of light with the least amount of light. Note that as the light amount adjusting means, any means can be used as long as it can limit the amount of light as described above, such as a light shielding ring that adjusts the amount of transmitted light depending on the size of the aperture, an ND filter, etc. Suitably used. Further, these light fflXll moderators may be integrated with or separate from the optical filter having wavelength selectivity described above.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic diagram of a concentration measuring device equipped with a light source device according to an embodiment of the present invention.

As described above, the illustrated concentration measuring device stores a sample liquid and irradiates each of a plurality of surfaces 6 to be measured, such as a chemical analysis slide kept at constant temperature, with light 2. The reflected light 2a is detected by a photodetector 7, and this light source device includes a xenon flash lamp 1 as a light source,
It consists of the same number of optical fibers 5 as the number of surfaces to be measured, each transmitting light emitted from the lamp to the plurality of surfaces 6 to be measured. The light 2 emitted from the xenon flash lamp 1 passes through the condenser lens 3 to the fiber input section 4 where the plurality of optical fibers 5 are integrally bundled with their input end faces 5a aligned on the same plane. It is often allowed to enter. Each optical fiber 5 is arranged such that its exit end surface 5b faces the surface to be measured 6, and the light 2 that enters each optical fiber 5 from the entrance end surface 5a is transmitted through the fiber and exits from the exit end surface 5b. , irradiates the surface to be measured 6. The lens 8 provided on the exit end surface 5b of each optical fiber 5 directs the light 2 emitted from the optical fiber 5 in a spread state to the surface to be measured 6.
The beam is focused to a predetermined beam diameter. Further, one photodetector 7 is provided corresponding to each surface 6 of #1P1, and the reflected light 2a generated from each surface to be measured 6 due to the irradiation of the light 2 is detected by the photodetector 7, respectively. After being detected, it is amplified by an amplifier (not shown).

The optical fiber 5 in the light source device is composed of a first fiber part 5A and a second fiber part 5B, which are connected by a fiber connecting part 10, respectively, and the optical fiber 5 in the light source device is composed of a first fiber part 5A and a second fiber part 5B, which are connected to each other by a fiber connection part 10. The light 2 covering the area is transmitted by the first fiber part 5A and then passes through the fiber connection part 1O, so that only the light of a specific wavelength corresponding to the measurement item on each measured surface 6 is transmitted to the second fiber part 5A. The signal is transmitted to the fiber section 5B. Hereinafter, the structure of the fiber connection section 10 will be explained with reference to FIG. 2.

The illustrated fiber connection section 10 is connected to the first fiber section 5
One end of A is held by the first fiber plug 11, one end of the second fiber part 5B is held by the second fiber plug 12, and both plugs are inserted into the plug holder 13 and held. , which connects both fiber sections. The first fiber plug 11 is attached to a first plug main body 11A that holds a first fiber section 5A and an end face of the first fiber section 5A, and is configured to transmit light emitted from the first fiber section 5A. The second fiber plug 12 consists of a lens IIB that once converts the light into parallel light, and the second fiber plug 12 includes a second plug main body 12A that holds the second fiber part 5B, and a second fiber part 5B.
The light emitted from the first fiber plug as parallel light is transmitted to the second fiber part 5.
It consists of a lens 12B that focuses the light before making it incident on B. Further, the plug holder 13 can removably accommodate therein an interference filter 20 that transmits only light of a wavelength selected in advance in accordance with the measurement item of the surface to be measured 6. That is, the plug holder 13 is
The first fiber plug 11 is entered from below.
It consists of a holder part 13A and a second holder part 13B into which the second fiber plug 12 enters from above, and the first holder part 13A has a recess formed in the upper part in which the interference filter 20 is placed. It is designed to let you do so.

In this way, an interference filter 2 is installed inside the fiber connection part lO.
0 and the first fiber section 5 through an interference filter.
If the end faces of the fiber section A and the second fiber section 5B are made to face each other, only the light in a predetermined wavelength range will pass through the interference filter 20, and only the light in a predetermined wavelength range will be selectively emitted from the first fiber section 5A. is made to enter the second fiber section 5B. Therefore, when measuring the concentration of the surface to be measured 6 as described above, if an interference filter having characteristics according to the measurement item is arranged in advance in the fiber connection part 10, the light emitted from the exit end face of the optical fiber 5 can be Predetermined items can be measured with high precision using light consisting only of desired wavelength components. Note that when the interference filter 20 is disposed within the fiber connection section 10, the end surface of the first fiber section 5A and the end surface of the second fiber section 5B are inevitably separated, so that light of the necessary wavelength can be transmitted well. Therefore, it is desirable to attach lenses IIB and 12B to the first and second fiber plugs 11.12, respectively, as described above.

Incidentally, the amount of light extracted from the light emitted from the xenon flash lamp 1 through the interference filter 20 differs depending on the wavelength.

Therefore, if you convert the interference filter according to the measurement item,
It is conceivable that the amount of light emitted from the exit end face 5b of the optical fiber changes each time. Therefore, in the fiber connection section 10, there is a light shielding ring that blocks a part of the light that has passed through the interference filter depending on the wavelength and keeps the amount of light that enters the second fiber section 5B almost constant. can be installed. That is, the second
A recessed portion capable of accommodating the light shielding ring 30 is formed at the lower end of the holder portion 13B, and the light shielding ring 30 is accommodated in the recessed portion while the peripheral portion of the lower end surface is supported by the first holder portion 13A. It is held within the fiber connection 10. The light-shielding ring 30 is made of a material that has light-shielding properties, and has an opening 3 of a predetermined size in the center.
0a, and the amount of light incident on the second fiber portion 5B is adjusted depending on the size of this aperture 30a. The size of this opening 30a is determined according to the characteristics of the interference filter 20, and when the interference filter 20 is replaced, the light shielding ring 30 is also replaced with another ring with a different size of opening 30a. Ru. That is, when an interference filter that transmits light of a wavelength with a relatively large amount of light is used, a light blocking ring having a relatively small aperture is used, and conversely, an interference filter that transmits light of a wavelength of a relatively low amount of light is used. If used, a shade ring with a relatively large aperture is used. Furthermore, when performing density measurement using light of a wavelength with the least amount of light, the light shielding ring 30 is not attached. Also,
Each of the above-mentioned light-shielding rings is selected and used so that the amount of light passing through the aperture is equal to the amount of light of a wavelength with a small amount of light. In the fiber connection part IO in this embodiment, as shown in the figure, the circumferential surfaces of the first holder part 13A and the second holder part 13B are threaded, and both holder parts are screwed together and integrated. Therefore, the interference filter 20 and the light shielding ring 30 can be replaced in the container by rotating both holder parts and releasing the screw engagement.

By adjusting the amount of light in the fiber connection part 1O in this way and making the amount of light emitted from the exit end face 5b of each optical fiber constant regardless of the wavelength of the light used for concentration measurement, each photodetector 7 can be Since the amplification factors of all the connected amplifiers can be made uniform, it is possible to measure arbitrary items at each light irradiation position. Note that the above-mentioned light shielding ring may be placed in front of the interference filter on the optical path of the light. Furthermore, since the type of light shielding ring is determined by the type of interference filter, the interference filter and the light shielding ring may be integrated. Moreover, various members other than the light shielding ring can be used as the light amount adjusting means for restricting the passage of light. For example, ND
You can attach a filter instead of a light shielding ring,
The amount of light may be adjusted by changing the distance between the first fiber part and the second fiber part within the fiber connection part. In the latter case, the means for relatively moving both fiber sections becomes the light amount adjusting means. Furthermore, the above-mentioned interference filter may be replaced with another optical filter having wavelength selectivity, such as colored glass. Further, as the light source, it is also possible to use something other than the above-mentioned xenon flash lamp. Further, the present light source device can also be used in a concentration Δp+ constant device that detects light transmitted through a surface to be measured.

(Effects of the Invention) As described above in detail, according to the concentration measuring device of the present invention, each optical fiber is made up of a first fiber part and a second fiber part connected by a fiber connection part, An optical filter that selectively transmits only light of a predetermined wavelength is detachably held in the fiber connection part, and a light amount adjustment means is provided, so that light of any wavelength can be freely transmitted while keeping the light amount constant. can be irradiated in the channels. Therefore, by using this light source device, it is possible to uniformize the amplification factors of the detection signals in each channel and measure any item on any channel.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a concentration measuring device using a light source device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of a fiber connection section. 1... Xenon flash lamp 2... Light 3... Condenser lens 5.
...Optical fiber 5A...First fiber part 5B
...Second fiber portion 5a...Incidence end surface 5b...Emission end surface 6...
Surface to be measured 10...Fiber connection part 20...
interference filter

Claims (1)

[Scope of Claims] Consisting of a light source and a plurality of optical fibers, each input end face of the plurality of optical fibers is brought close to the light source so that the light emitted from the light source is input to the plurality of optical fibers, and the light emitted from the light source is incident on the plurality of optical fibers. In a concentration measurement light source device that brings each exit end face of an optical fiber close to a different surface to be measured, and irradiates the light onto each surface to be measured in order to measure the concentration of the surface to be measured, wherein each of the optical fibers is , consisting of a first fiber part and a second fiber part connected by a fiber connection part, and the fiber connection part connects the first fiber part with an optical filter that selectively transmits only light of a specific wavelength. The fiber connection part restricts the passage of the light so that the light passes through the fiber connection part regardless of the wavelength of the light transmitted by the optical filter. A light source device for concentration measurement, comprising a light amount adjusting means for making the amount of light substantially constant at least when the optical filter is inserted.