JPS605897B2 - spectrofluorometer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a spectrophotometer in which light from a light source is selected by an excitation spectrometer, and when a sample is irradiated with the light, the light emitted is spectrally separated by a crab light spectrometer.

The secondary spectrophotometer is shown in Figure 1. A light source 1 emits continuous wavelength light over a wide wavelength range, such as a Xe lamp, and the light is spectrally selected by an excitation spectrometer 2. When the sample 8 is irradiated with light of a short wavelength selected by the excitation spectrometer 2, the sample emits light unique to its components. The honey light enters the crab light spectrometer 9 and is split into spectra, and then detected by the detector 10. Although the electrical signal from the detector is omitted in FIG. 1, it is processed by the electrical system and displayed on the indicator 11 as a spectral light amount. A recorder may also be used in conjunction with the above-mentioned indicator.
When analyzing an unknown sample using the spectrophotometer described above, first fix the wavelength of the spectrometer 9 to the wavelength at which the honeydew of the sample is expected to appear, and then set the wavelength of the excitation spectrometer 2 The wavelength side is scanned to record a so-called excitation spectrum curve.

This allows the wavelength of excitation light that easily excites fluorescence to be known.
Next, the wavelength of the excitation spectrometer 2 is fixed to a wavelength that strongly generates honey light, and the wavelength of the crab light spectrometer 9 is scanned to record a saddle light spectrum curve. From the above spectral curve, the constituent substances in the sample that emit crab light can be determined, and the approximate content thereof can be known. FIG. 2 is a diagram showing the above-mentioned excitation spectrum curve and crab light spectrum curve, where the vertical axis indicates the intensity of crab light with 1;
The axis represents the wavelength in increments.

a is the excitation spectrum curve and b is the crab light spectrum curve. The wavelength at which both curves approach ^s is determined by the substance, and curves a and b have a mirror image relationship (
mirror symmetry). Although the mirror image relationship described above does not clearly exist in all crab-light substances, for example, benzene etc. draw a diagram similar to that shown in Figure 2, and its input s is approximately 2.
It is 7m. In general, the long-wavelength side of curve a and the short-wavelength side of curve b overlap or are completely separated from each other in general saddle-light materials, so in this case, the long wavelength end of curve a and the short wavelength end of curve b can be identified as It may be assumed that the wavelength input is s,,^s2. After identifying the crab-light substance in the sample as described above, or when quantifying a known crab-light substance, excite the sample with as much excitation spectrum light as possible to obtain the crab light spectrum b.
By measuring the total amount of fluorescence in the range of , it is possible to quantify the crab light component with high sensitivity.

The present invention relates to a spectrophotometer that can perform measurements in this manner. An example of a secondary method is when the sample is directly irradiated with light from a light source such as a Xe lamp that emits strong light in the ultraviolet to visible wavelength range. At this time, the measurement accuracy is low because the scattered light (wide wavelength range light) of the irradiation light enters the detector as stray light together with the sample image light. In some cases, the light from a mercury lamp is passed through a filter to cut out unnecessary wavelength light, and the sample is irradiated with this light. In this case, since the excitation light has a line spectrum, there is an advantage that there is less stray light in the crab light spectrometer, but there is a disadvantage that the amount of excited light is small because the amount of excitation light is small. The secondary spectrophotometer shown in Figure 1 excites the sample with short-wavelength light that is spectrally separated, and the light generated by the sample is emitted into the spectrometer, so the amount of light that reaches the detector is small. Naturally, the sensitivity is low and the S/N
The ratio was low. The purpose of the present invention is to eliminate the above-mentioned conventional drawbacks,
To provide a spectrophotometer that can detect a large amount of light and measure with high precision.

The main point of the present invention is as shown in Fig. 2. , using an excitation spectrometer that can select wavelengths of excitation spectrum light over a wide wavelength range.

This allows more powerful excitation light to be obtained than in the past, increasing the amount of light emitted by the sample. Furthermore, since the excitation light mentioned above does not irradiate the sample with long wavelength light, the scattered light does not include honey light and double long wavelength light from the sample, making pure crab light measurement possible. . The main point of the second invention is that, in combination with the excitation spectrometer, a spectroscopic spectrometer is used which can select a wide range of wavelength light on the longer wavelength side than the specific wavelength input s. This crab light spectrometer detects all the crab light with a wide range of wavelengths generated by the sample, but this detection light does not include short wavelength light (excitation light) scattered by the sample, so the measurement accuracy is low. It will improve. Third
The figure is an explanatory diagram of a spectrophotometer that is an embodiment of the present invention.

Although this example uses a concave diffraction grating as the dispersion element of the excitation spectrometer, other dispersion elements such as a prism or a plane diffraction grating and a concave mirror may be used in combination. In FIG. 3, light emitted from a light source 1 emitting light with a wide range of wavelengths passes through an entrance slit 3 of an excitation spectrometer 2, and is then diffracted by a concave diffraction grating 4 to produce a spectrum on a Rowland circle 12. The above specific wavelength of the spectrum
A wavelength range selection mirror 5 selects only the light having a wavelength shorter than that of the wavelength range selection mirror 5, and the light is outputted from the output slit 6. This light is collected by the condensing mirror 7
When the light is focused and incident on the sample 8, the sample emits crab light. Since the light that irradiated the sample does not include light with a wavelength longer than ^s, the light scattered by the sample does not include light in the same wavelength range as the crab light. Further, short wavelength excitation light scattered by the sample enters the fluorescence spectrometer 9 together with the afterglow of the sample, but is separated and removed, and only long wavelength light is emitted. Therefore, only the separated light of pure crab light reaches the detector 101, and the amount of light is displayed on the display 11 and quantitatively analyzed. Since the image of the concave diffraction grating 4 is generated on the output slit 6 of the excitation spectrometer 2, the inside of the slit is widened to increase the amount of output light.

When changing the specific wavelength light ^s to a different wavelength, the purpose can be achieved by rotating the concave diffraction grating 4 because the spectral wavelength range reflected by the wavelength range selection mirror 5 changes. In this embodiment, since the sample is not irradiated with light having a wavelength longer than the specific wavelength input s, the scattered light does not enter the crab light spectrometer and overlap with the fluorescence, so it does not interfere with measurement accuracy.

In addition, since the amount of light with a shorter wavelength is larger than the amount of light with a shorter wavelength than the beam irradiating the sample, there is an advantage that the amount of light emitted by the sample is larger than that of the conventional method, and the wavelength range of the excitation light can be selected. FIG. 4 shows another embodiment of the invention. The difference from Fig. 3 is that the concave mirror 13 corresponding to the wavelength range selection mirror 5 is made large, and the Roland circle 12 is close to its reflecting surface.
The wavelength range selection plate 14 is movably installed along the wavelength range selection plate 14, and the concave diffraction grating 4 does not need to be rotated. To change the wavelength position of the specific wavelength ^s, the wavelength range selection plate 14 is moved. This embodiment has the advantage that the same effect can be obtained with a simple excitation spectrometer that only requires a fixed concave diffraction grating and a mechanism for moving the wavelength range selection plate.

The second invention related to the spectrophotometer is the use of a spectrophotometer that emits only light with a longer wavelength than the specific wavelength in combination with the excitation spectrometer of the first invention. Fig. 5 is an explanatory diagram of a spectrophotometer which is an embodiment of the second invention.Excitation spectrometer 2 and sample 8 are the same as in the example shown in Fig. 3, so their explanation is omitted. The incident light of the saddle spectrometer 9 is transmitted through the rotatable concave diffraction grating 4.
A spectrum is generated on the Rowland circle 12 diffracted by . The entrance slit side of the spectrum is the short wavelength side, and the other end is the long wavelength side. Letting s2 be the wavelength of the spectrum on the incident slit side reflected by the wavelength range selection mirror 5, this wavelength is the specific wavelength explained in FIG. 2. Second
In the figure, the specific wavelength is a common wavelength for the excitation spectrum curve a and the crab light spectrum curve b, but in this example, the specific wavelength of the excitation spectrometer 2 is input so that it can be applied to all crab light substances. , , the specific wavelength of the crab light spectrometer can be determined as input S2. In this way, the input s.e. By exciting the sample with only the shorter wavelength light, the full-spectrum spectrometer 9 can detect all the crab light present in the wavelength range longer than ^s2, which is the short wavelength end of the crab light spectrum. If the sample is replaced and shows a different specific wavelength, the concave diffraction grating 4 of the excitation spectrometer 2 is rotated to adjust the wavelength of the input s, according to the specific wavelength, and the concave diffraction grating of the crab spectrometer 9 is adjusted. Rotate grid 4 and enter
Adjust the wavelength of 2. In this example, since the wavelength range of the sample excitation light and the wavelength range of the light emitted from the crab light spectrometer can be selected, it is possible to measure with high precision only the pure total radiation light that does not contain any anti-inhibition light. effective. FIG. 6 shows another embodiment of the second invention, in which both spectrometers use the same type of spectrometer as the excitation spectrometer of FIG.

That is, since the position of the wavelength range selection plate 14 is variable along the Rowland circle 12, it is possible to expand or contract the wavelength range to be selected. The excitation spectrometer 2 does not emit light with a longer wavelength than the specified wavelength s2, and the crab spectrometer 9 does not emit light with a shorter wavelength than the specified wavelength s2, as in the case of Fig. 5 above. It's the same. In the case of this embodiment, the concave diffraction gratings 4 of both spectrometers may be fixedly installed. The effect of this embodiment is that, like the embodiment shown in FIG. 5, the total light of the sample can be measured with high accuracy in a pure state.

The spectrometers used in each of the above examples all used concave diffraction gratings, but other types of prism spectrometers or spectrometers that use a flat diffraction grating and concave mirror can also be used. It can be applied to vessels.

The above two inventions make use of the characteristic that the excitation spectrum of the crab-light substance and the wavelength position of the honey-light spectrum are different, to efficiently detect the afterglow of the sample and to perform highly accurate crab-light measurement with a high S/N ratio. It has the remarkable effect of making it possible.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a conventional spectrophotometer, Fig. 2 is a diagram showing the relationship between the excitation spectrum and the crab light spectrum, and Fig. 3 is a diagram of a spectrophotometer that is an embodiment of the present invention. 4 is an explanatory diagram of a spectroscopic crab photometer which is another embodiment of the present invention. FIG. 5 is an explanatory diagram of a spectroscopic crab photometer which is an embodiment of the second invention. The figure is an explanatory diagram of a spectrophotometer that is another embodiment of the second invention. Explanation of symbols: 1...Light source, 2...Excitation spectrometer, 3...Incidence slit, 4...
Concave diffraction grating, 5...Wavelength range selection mirror, 6
・・・Output slit “ 7 ・・・Collecting mirror 8
Skin...sample "9...crab spectrometer, 10...detector, 11...display device, 12...Roland circle,
13... Concave mirror, 14... Wavelength range selection plate. Hair l figure 2 figure multiple hair figure 4 figure multiple figure 5 figure

Claims (1)

[Scope of Claims] 1. A light source that generates light with a wide range of wavelengths, an excitation spectrometer that spectrally spectra the light emitted by the light source and select the wavelength of the emitted light, and a light source that generates light from a sample by irradiation with the emitted light of the excitation spectrometer. A fluorescence spectrometer that separates the fluorescence to select the wavelength of the emitted light, a detector that detects the emitted light of the fluorescence spectrometer, and processes the electrical signals from the detector to be emitted by the sample. In the spectrofluorophotometer, the excitation spectrometer includes a rotatably installed dispersion element that separates the light incident from the entrance slit and forms an image of the spectrum; A spectrofluorophotometer comprising a condensing element installed at the spectral imaging position and condensing only a spectrum on the shorter wavelength side than a specific wavelength and emitting it from an output slit. 2. A light source that generates light with a wide range of wavelengths, an excitation spectrometer that spectrally spectra the light emitted by the light source and select the wavelength of the emitted light, and a spectrometer that spectrally spectra the fluorescent light generated from the sample by irradiation with the emitted light of the excitation spectrometer. a fluorescence spectrometer that selects the wavelength of the emitted light, a detector that detects the emitted light of the fluorescence spectrometer, and a display that processes electrical signals from the detector and displays the amount of fluorescence emitted by the sample. In the spectrofluorophotometer, the excitation spectrometer includes a rotatably installed dispersion element that separates the light incident from the entrance slit and forms an image of the spectrum, and a dispersion element that is rotatably installed at the spectral imaging position. The fluorescence spectrometer consists of a condensing element that is installed to condense only the spectrum on the shorter wavelength side than a specific wavelength and output it from an output slit. It consists of a dispersion element rotatably installed to image the spectrum, and a condensing element installed at the spectrum imaging position to focus only the spectrum with a wavelength longer than the specific wavelength and output it from the output slit. A spectrofluorophotometer characterized by: