JPS61202143A - Absorbance measuring apparatus - Google Patents

Abstract

PURPOSE:To enable a highly accurate absorption analysis using a Xe flash lamp, by making light of the Xe flash lamp into a sample through a diffusion plate and further the transmission light into a detector through a spectral analysis to calculate the absorbance with several wavelength differences from the output thereof. CONSTITUTION:A high voltage from a high voltage power source 10 is applied to a Xe flash lamp 1 under the control with a CPU11, a pulse light generated is transmitted through a sample in a diffusion plate 2, a condenser lens 3a and a reaction tube 4 and spectrally analyzed with a diffraction grating 6 via a condenser 3b and a slit 5 to be made incident into a detector 7. The output is inputted into an arithmetic means 9 via an amplifier 8. The absorbance with several wavelengths is calculated by the arithmetic means 9. A highly accurate absorption analysis can be done with the stabilization by the diffusion plate 2 using the Xe flash lamp 1.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an absorbance measurement device in an automatic chemical analyzer, and more specifically, to a device for measuring absorbance in an automatic chemical analyzer, and more specifically, it projects light from a light source into a reaction cell, and then spectrally spectra it into multiple wavelengths. The present invention relates to a post-spectroscopic absorbance measuring device that measures absorbance using a post-spectroscopic method.

[Technical Background of the Invention] In automatic chemical analysis and the like, by directly measuring the light of a reaction tube containing a specimen, it is possible to measure the absorbance of a much smaller amount of specimen compared to the conventional 70-cell type.

This direct photometry method includes a pre-spectroscopic method in which monochromatic light from a spectrometer is incident on a reaction tube and absorption analysis is performed, and a post-spectroscopic method in which light transmitted through the reaction tube is spectrally divided and absorption analysis is performed.

Since problems associated with stray light cannot be avoided with the front spectroscopy method, in recent years many models have adopted the rear spectroscopy method.

In this case, continuous light such as a halogen tungsten lamp is often used as the light source.

[Problems with background technology] Enzyme activity reaction (RA), which occupies the mainstream of recent biochemical analysis methods,
In the measurement using the TE method, the photometric wavelength used for measurement is 3.
It is concentrated in the ultraviolet region of 40 nm.

By the way, the halogen tungsten lamp does not emit light.
Although it has the advantage of being a stable light source with little variation in points, as shown in Figure 1 (a), the amount of light in the ultraviolet region is nearly 100 times lower than the peak amount of visible light. For this reason, even with the sensitivity characteristics of the latest semiconductor detectors (see Figure 1), extremely high S-
N ratio is required.

Also, if a halogen tungsten lamp is used to secure a certain amount of light in the ultraviolet region, the output (wattage)
must be increased. Therefore, a stabilized power source with high output is required, and the problem of heat generation due to high output also occurs. For example, in the post-spectroscopy method, a considerable amount of light enters the reaction tube, resulting in photodecomposition of the sample, which has a large thermal effect.

Furthermore, with the recent advances in optical fiber technology, optical fibers are being used as light guides in absorbance measurement devices, but the low filling rate of the optical fibers used results in large optical losses and leads to low light intensity. It has become difficult to use optical fiber.

Therefore, xenon flash lamps are attracting attention as a new light source to replace the halogen tungsten lamps. A xenon flash lamp emits high-intensity light using a pulse lighting method, as shown in Figure 1 C.
As shown in FIG. 2, the amount of light from a xenon flash lamp in the ultraviolet region reaches approximately 1000 times the amount of light from the tungsten halogen lamp. Furthermore, since the flash time of the xenon flash lamp is as short as several microseconds, the integral value of the amount of light per unit of time is extremely small and does not adversely affect the chemical reaction. Thus, by using a xenon flash lamp, all the drawbacks of tungsten halogen lamps can be overcome.

However, the xenon lamp has the disadvantage that its light emitting point varies, and the xenon flash lamp using the pulse lighting method has the disadvantage that the variation is even greater and it is unstable as a light source.

Therefore, the xyrenon flash lamp, which is ideal in terms of light intensity and heat generation, is currently not used in absorbance measurement devices because of its only drawback of lacking stability as a light source.

[Purpose of the Invention] This invention has been made in view of the above circumstances, and an object thereof is to provide an absorbance measurement device that can perform absorption analysis of highly refined marks while using a xenon flash lamp as a light source. It is something to do.

[Summary of the Invention 1] A summary of the present invention for achieving the above-mentioned object is to provide a xenon flash lamp that emits high-brightness light in a pulsed manner, and a a diffusion plate that homogenizes the light emitted by the lamp; a high-voltage N8I that applies a high pulse voltage to the xenon flash lamp for the same sample; and a high voltage N8I that applies a pulse high voltage to the xenon flash lamp for the same sample; It is characterized by having a spectroscopic element that performs spectroscopy, a detector that detects monochromatic light from the spectroscopic element, and a calculation means that inputs the output of the detector and calculates the absorbance value of a plurality of wavelength differences. be.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram of an absorbance measuring device that is an embodiment of the present invention. In FIG. 2, a xenon flash lamp 1 emits high-intensity light using a pulse lighting method. The diffuser plate 2 is provided close to the xenon flash lamp 1 and moves so that the light emitted from the xenon flash lamp 1 becomes uniform light with little vibration.

The high voltage power supply 10 applies a high voltage to the same sample under the control of the CPU 11 so as to pulse-light the xenon flash lamp 1.The condensing lens 3a collects the light from the xenon flash lamp 1 into the reaction tube 4. lead to. The transmitted light of the sample in the reaction tube 4 is guided to, for example, a diffraction grating 6 via a condenser lens 3b and Surins 1 to 5. The diffraction grating 6 converts the transmitted light into multiple wavelengths, for example, two wavelengths λ1. Split into λ2. Detector 7 detects wavelength λ1. Detect monochromatic light of λ2. The amplifier 8 inputs the output of the detector 7, amplifies it, and outputs it. The calculation means 9 calculates the wavelength λ1 . Transmitted light II(λ1), 1(λ2
) to find the absorbance value of the difference between the two wavelengths.

The operation of the absorbance measuring device configured as above will be explained.

When pulsed light is emitted from the xenon flash lamp 1 to the same sample in the reaction tube 4, this pulsed light is made uniform by the diffusion plate 2 and then passes through the sample in the reaction tube 4. The light is incident on the sequential order diffraction grating 6. This diffraction grating 6 has a wavelength λ1. The light separated into wavelengths of λ2 is detected by a detector 7, and the output of the detector 7 is inputted to an arithmetic means 9 via an amplifier 8.

As a result, the calculating means 9 calculates two wavelengths λ1. Obtain the absorbance value of the difference in λ2.

Although the case has been described in which it is provided close to the flash lamp 1, it may also be provided in contact with the emission surface of the xenon flash lamp 1.

[Effects of the Invention] As explained above, according to the present invention, even though a xenon flash lamp is used as a light source, it can be made into a stable light source by using a simple optical material such as a diffuser plate, resulting in high precision. It is possible to provide an absorbance measurement device that performs absorption analysis. Therefore, the advantages of using a xenon flash lamp as the light source of the absorbance measurement device include securing a predetermined amount of light in the ultraviolet region, preventing photodecomposition of the sample, and using an optical fiber with a low filling rate. .

[Brief explanation of drawings]

FIG. 1 is a characteristic diagram showing the light intensity of a halogen tungsten lamp and a xenon flash lamp and the sensitivity of a semiconductor detector for each wavelength, and FIG. 2 is a block diagram of an absorbance measuring device which is an embodiment of the present invention. 1...Xenon flash lamp, 2...
... Diffusion plate, 4 ... Reaction tube, 6 ... Spectroscopic element, 7 ... Detector, 9 ... Calculation means, 10 ... ...High voltage power supply. Agent: Patent attorney Kensuke Norichika (1 person) included (m7n-)

Claims (1)

[Claims] An absorbance measurement device that analyzes the absorbance of a sample after a color reaction includes a xenon flash lamp that emits high-intensity light in a pulsed manner, a diffuser plate that homogenizes the light emitted by the xenon flash lamp, and a xenon flash for the same sample. a high-voltage power supply that applies a pulsed high voltage to the lamp; a spectroscopic element that makes light emitted by the xenon flash lamp incident through the sample and spectrally spectra it; and a detector that detects the monochromatic light from the spectroscopic element. , and a calculation means for inputting the output of the detector and calculating absorbance values for a plurality of wavelength differences.