JPS61233326A - Multi-wavelength simultaneous photometry photometer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a multi-wavelength simultaneous photometer used in liquid chromatography or general routine analysis.

This invention relates to a multi-wavelength simultaneous photometer that requires high performance in terms of photometric linearity, etc.

[Background of the invention]

A conventional multi-wavelength simultaneous photometry photometer is, for example,
As shown in No. 39849, 1 essentially measures light in the ultraviolet or visible range by switching between a deuterium lamp and a tungsten lamp, and does not literally measure light in the entire wavelength range at the same time. By repeating these steps at high speed, quasi-simultaneous photometry is possible, but it is necessary to insert and remove filters in synchronization with switching, which puts strain on the mechanical system overall. Furthermore, even if the switching time is ignored, 1/2 of the light energy is wasted. So, I used a semi-transparent mirror.

Although there is a method of guiding the light from two types of light sources to the same optical axis at the same time, 172 of the light energy must be discarded, and secondary light removal and stray light removal are difficult to perform.

[Purpose of the invention]

The purpose of the present invention is to simultaneously measure multiple wavelengths in the wavelength range from ultraviolet to visible light without losing light energy, that is, without impairing sensitivity, and to increase linearity of photometric values and increase wavelength resolution. The purpose of the present invention is to provide a photometric photometer.

[Summary of the invention]

The present invention does not provide a detector on the spectral plane of the main spectrometer at the rear of the sample chamber, but instead provides a front spectrometer in front of the other sample types in the main spectrometer to correspond to wavelength ranges on the spectral plane. The light energy is not lost by splitting the light beam into two parts, refocusing each of the split light beams, and then inputting them into separate detectors.
It is possible to perform simultaneous photometry in the wavelength range from ultraviolet to visible, increasing the linearity of photometric values and increasing wavelength resolution.

Therefore, according to the present invention, ultraviolet light and visible light can be placed on the same optical axis without energy loss by using both the first-order optical path and the zero-order optical path of the prespectroscope. Furthermore, according to the present invention, secondary light and stray light can be almost completely removed by linking the wavelength range selection by the front spectrometer and the selection of filters inserted in front of each detector of the main spectrometer. can be done. Furthermore, according to the present invention, the selection of the short wavelength range by the front spectrometer and the removal of the shortcut filter in front of the detector for visible light measurement are performed in conjunction with each other, so that the first-order dispersed light and the second-order dispersed light of ultraviolet light are It is possible to improve the S/N by measuring both. Furthermore, according to the present invention, since a plurality of detectors are used depending on the wavelength range, resolution can be improved even if a detector with a small number of bits is used, and by separating on the spectrum plane, The harmful effects of separation can be eliminated.

[Embodiments of the invention]

An embodiment of the present invention will be described below.

FIG. 1 shows an embodiment of the present invention.

In the figure, inside the spectrometer unit 1, there is a front spectrometer which is a zero-dispersion double spectrometer using concave diffraction gratings 8 and 10, that is, a reduced dispersion double spectrometer where 1 dispersion is exactly canceled, and a concave diffraction grating. 16, and includes a main spectrometer consisting of a beam splitter and two multichannel detectors, and a sample chamber 14. Furthermore, a deuterium lamp 2 and a tungsten lamp 3 are present outside the spectrometer unit 1.

The ultraviolet light emitted from the deuterium lamp 2 enters the Fuku spectrometer through the emission slit 6 after being focused by the lens 5.
The light passes through the mirror 7 and enters the concave diffraction grating 8 . Of the light dispersed by the concave diffraction grating 8, light in a specific wavelength range is
It passes through the intermediate slit 9. Generally, the intermediate slit 9 is not intended to extract monochromatic light, but rather to extract light in a wide and constant wavelength range.

The slit spacing is wide and the intermediate slit switching mechanism 26
The structure is such that a different wavelength range can be selected by switching.

The light passing through the intermediate slit 9 passes through the second concave diffraction grating 1
The light is again dispersed by zero, but the one dispersion direction is opposite to that of the first concave diffraction grating 8, and at the position of the exit slit 11, there is no wavelength dispersion, and the light is concentrated at one location. However, since the wavelength range is already limited by the intermediate slit 9, the light passing through the slit 11 is not completely white light.

Light in a specific wavelength range is mixed to form white light. The light that has passed through the output slit 11 is focused by a lens 13 and passes through a flow cell 15 in a sample chamber 14 . The light passing through the flow cell 15 enters the concave diffraction grating 16 with the inner wall of the flow cell 15 serving as an entrance slit for the main spectrometer. After being dispersed by the concave diffraction grating 16, the mirror 17
At this spectral image position, there is a wavelength division mirror 2.0, and the short wavelength light is again converged by the toroid mirror 18.

A spectral image is formed on the light receiving surface of the photodiode array detector 19. Long wavelength light is transmitted by toroid mirror 21
The light is converged again and a spectral image is formed on the light receiving surface of the photodiode array detector 22. A filter insertion mechanism 23 is provided in the long wavelength photometry path so that a shortcut filter 23 can be inserted depending on the measurement mode.

On the other hand, the visible light emitted from the tungsten lamp 3 is.

The light is focused by the lens 5, passes through the heat ray cut filter 25, passes through the mirror 12, and heads toward the second concave diffraction grating 10. At this time, the optical axis of the light travels is the concave diffraction grating 1.
With respect to the normal line of 0, the position is symmetrical to the optical axis of the light emitted. That is, the light that exits the tungsten lamp and enters the concave diffraction grating 10 is designed so that its zero-order diffracted light emerges from the exit slit.

Figures 2 and 3 show the progress of light in the measurement mode. In Figure 0, the solid line shows the ultraviolet light emitted from the deuterium lamp, and the broken line shows the visible light emitted from the tungsten lamp. .

Moreover, the dashed line indicates the secondary dispersed light of the ultraviolet light. FIG. 2 is an explanatory diagram of the simultaneous photometry mode of ultraviolet and visible light, and the intermediate slit 9 allows light in a wavelength range of 600 nm to pass through the 20 nm. In other words, most of the ultraviolet light and a small amount of visible light emitted by the deuterium lamp pass through the double spectrometer and head toward the blow cell 15, and in addition to this, the light from the tungsten lamp that enters the rear spectrometer in the double spectrometer, In other words, visible light is added, and 600 nm from 200 nm
A light beam having high energy over a range of nm or more is directed toward the flow cell 15. The light passing through the flow cell is dispersed by the concave diffraction grating 16 of the main spectrometer, while the ultraviolet light passes through the toroid mirror 18 and enters the photodiode array detector 19. On the other hand, the secondary light of visible light and ultraviolet light goes to the photodiode array detector 22 via the toroid mirror 21, but the secondary light of ultraviolet light is removed by the shortcut filter 23, and only the visible light passes to the detector. enter.

FIG. 3 is an explanatory diagram of how light travels in the ultraviolet light high sensitivity measurement mode. The difference from Fig. 2 is that the tungsten lamp 3 is off, and the middle slit 9 is
The filter that was in front of the visible range detection s22 was removed to allow only ultraviolet light of 300 nm to pass through.

Is the signal between 200 and 600 nm output to the outside?
At ~300 nm, it is determined whether the weighted average of the primary optical signal and secondary optical signal of each wavelength is output to the outside.

Therefore, according to this embodiment, ■200 to 600 nm
It should be easy to switch between the range measurement mode and the 200-300 nm range high sensitivity measurement mode.

■ Even with a photodiode array detector with a small number of bits, it is possible to measure in the 200 to 600 nm range by using two of them. There should be no loss of light quantity at the stage of mixing the light, there should be no harmful effects near the division/shifting of wavelength range division, and there should be no loss of light intensity at the stage of mixing light,
■In the measurement mode in the 200-300 nm range, the S/N of data can be increased by actively utilizing secondary dispersion light, and light of 300 nm or more is mixed in as stray light. This has the effect of preventing such problems and increasing the linearity of photometric values.

〔Effect of the invention〕

According to the present invention, since stray light and secondary light can be effectively removed in both the ultraviolet region mode and the ultraviolet-visible region mode, there is an effect that the measured values show good linearity in a wide range.

According to the present invention, in the ultraviolet-visible mode, when mixing the light from the ultraviolet light source and the light from the visible light source, there is no energy loss because a semi-transparent mirror or a time-sharing method is not used. This has the effect of making it possible to perform high-sensitivity measurements since there is no loss at the dividing section even when the light beam is guided to a plurality of detectors.

Further, according to the present invention, since secondary dispersion light is utilized even in the ultraviolet region mode, there is an effect of increasing sensitivity.

Furthermore, there is an effect that measurement can be easily performed by switching between the two modes described above.

[Brief explanation of the drawing]

Fig. 1 is a diagram of the optical system in the embodiment of the present invention, Fig. 2 is an explanatory diagram of the ultraviolet-visible region mode in the embodiment, Fig. 3 is an explanatory diagram of the ultraviolet region mode in the embodiment, and Fig. 4 is an explanatory diagram of the ultraviolet region mode in the embodiment. It is a functional system diagram in an example. 1... Spectrometer unit, 2... Deuterium lamp, 3...
...Tungsten lamp, 4...Lens, 5...Lens, 6...Incidence slit, 7...Mirror, 8...
- Concave diffraction grating, 9... Intermediate slit, 10... Concave diffraction grating, 11... Output slit, 12... Mirror, 13... Lens, 14... Sample chamber, 15.・
・Flow cell, 16... Concave diffraction grating, 17... Mirror, 18... Toroid mirror, 19... Photodiode array detector, 2o... Wavelength range division mirror,
21... Toroid mirror, 22... Photodiode array detector, 23... Shortcut filter, 24... Filter attachment/detachment mechanism. 25... Heat ray cut filter, 26... Intermediate slit selection mechanism.

Claims (1)

[Claims] 1. A photometer having a light source, a sample chamber, a spectroscopic means, and a detector including a plurality of detection elements, in which a light source is provided in addition to the first spectroscopic means located between the sample chamber and the detector. A multi-wavelength simultaneous photometry photometer, characterized in that a second spectroscopic means is provided between the sample chamber and the sample chamber to limit the wavelength range of light entering the sample chamber. 2. In the invention as set forth in claim 1, an inverse dispersion double spectrometer is used as the second spectroscopy means, and a wavelength range is selected by an intermediate slit. Photometric photometer. 3. In the invention described in claim 1 or 2, a sub-light source is provided in addition to the main light source, and a diffraction grating is used as the dispersion element of the second spectroscopic means, so that the first-order dispersed light of the main light source is A multi-wavelength simultaneous photometry photometer characterized in that the second-order dispersed light from the sub-light source and the second-order dispersed light from the sub-light source are made to overlap and enter the sample chamber. 4. A multi-wavelength simultaneous photometer according to the invention as set forth in claim 3, characterized in that a deuterium lamp is used as the main light source and a tungsten lamp is used as the sub-light source. 5. A multi-wavelength simultaneous photometer according to the invention as set forth in claim 3, characterized in that a tungsten lamp is used as the main light source, and a deuterium lamp is used as the sub-light source. 6. A first spectroscopic means comprising a light source, a sample chamber and a detector comprising a plurality of detection elements, a first spectroscopic means located between the sample chamber and the detector, and a second spectroscopic means between the light source and the sample chamber. In a multi-wavelength simultaneous photometry photometer equipped with a spectroscopic means, a plurality of the above detectors are provided according to the wavelength range, and in a mode in which only the short wavelength region is measured, the long wavelength light is cut in the second spectroscopic means. A multi-wavelength simultaneous photometry photometer, characterized in that the detector for the long wavelength range is used for secondary light measurement or higher order light measurement of short wavelength light. 7. In a photometer that has a light source, a sample chamber, a spectroscopic means, and a detector consisting of a plurality of detection elements, the dispersed light in the spectroscopic means passes through a mirror in the light beam near the plane where it converges for each wavelength, that is, the spectral image plane. A multi-wavelength simultaneous photometer that divides a luminous flux into multiple optical paths according to the wavelength range by inserting the light into the detector, and reconverges the light onto a detector in each optical path.