JP2745576B2 - Spectrophotometer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a spectrophotometer, and more particularly, to an adapter installed in a sample section.

(Prior Art) A spectrophotometer using a one-dimensional image sensor such as a photodiode array as a photodetector as a liquid chromatograph detector is commercially available. When a one-dimensional image sensor is used in a spectrophotometer, the entire spectral spectrum can be measured at one time, so wavelength tracking type tracking analysis can be used for tracking analysis of samples whose component concentration changes over time, such as liquid chromatograph effluent. In recent years, they have been widely used because they are superior to spectrophotometers. On the other hand, in optical spectroscopy, if optical fibers are used to introduce light into the sample or transmit light from the sample to the spectrometer, the degree of freedom in the shape of the light source or the sample, the position of the sample, etc. increases, and transmission also occurs. Since it is easy to switch between measurement methods such as measurement and reflection measurement, a spectrophotometer using an optical fiber for transmitting light to a spectroscope and using a one-dimensional image sensor as a photodetector is also commercially available. Although each of these devices is expensive, it is used exclusively for liquid chromatograph detectors, or for general measurement using optical fibers and is unsuitable for liquid chromatograph detectors. In order to cope with this, the above two types of spectrophotometers must be prepared, and the economic burden on the department in charge of analysis becomes very heavy.

(Problems to be Solved by the Invention) A spectrophotometer using a one-dimensional image sensor as a photodetector has a characteristic that data of a spectral spectrum can be collected at a time and a liquid chromatograph detector. It is an object of the present invention to obtain a spectrophotometer having characteristics that can be applied to various samples and measurement methods (transmittance measurement, reflectance measurement, etc.).

(Means for Solving the Problems) A spectroscope configured to form a spectral image on a one-dimensional image sensor, a light source attached to the spectroscope, and a plurality of types detachably attached to a sample chamber of the spectroscope. A spectrophotometer is constituted by the adapters, the sample liquid flows through these adapters, the light from the light source passes through the adapter, and the flow cell enters the spectrometer, and the light from the light source at an arbitrary position is held. An optical fiber holder holding an optical fiber that guides the optical fiber to the spectroscope, holding two optical fibers, causing the light of the light source to enter one optical fiber, and separating the light incident from one end of the other optical fiber into the spectral fiber There are three types of optical fiber holders to be incident on the instrument, and each adapter is compatible with its external shape and the window of the sample chamber of the spectrophotometer. The position in the sample chamber was determined by the fitting.

(Operation) Since the spectrophotometer of the present invention has a plurality of adapters which can be attached to and detached from the sample chamber of the spectrometer using the one-dimensional imaging device as a photodetector, these adapters can be exchanged for the spectrometer. Therefore, by replacing these adapters, a single spectrometer can perform a plurality of types of measurements. Since one of the adapters is a flow cell, the spectrophotometer of the present invention can be used as a detector in a liquid chromatograph, and the other adapter has one or two optical fibers.
Light from a light source at an arbitrary position is incident on one optical fiber through the sample and guided to the spectroscope, and measurement of the sample that cannot be installed in the sample chamber, or spark discharge or plasma flame different from the light source attached to the spectroscope A variety of measurements can be performed with a single spectrometer, such as the ability to perform luminescence analysis using this light source. And since each adapter is positioned by matching with the window of the sample chamber, and itself becomes the lid of the window of the sample chamber,
In addition, no positioning means is required, no lid is required, the structure is simple, and the number of replacements is also simple.

(Embodiment) FIGS. 1A, 1B, and 1C show three types of use states of an apparatus according to an embodiment of the present invention. In these figures, reference numeral 1 denotes a spectroscope, S denotes an entrance slit, G denotes a diffraction grating, D denotes a photodiode array, and a spectrum image by the diffraction grating G is formed on a light receiving surface thereof. Reference numeral 2 denotes a signal processing circuit which reads the output of the photodiode array and performs various data processing.
Reference numeral 3 denotes a shutter provided on the front surface of the slit S of the spectroscope 1, and denotes a sample chamber mounted on the front surface of the spectroscope 1.
Reference numeral 5 denotes a light source, and reference numeral 6 denotes a condensing optical system that condenses light from the light source onto the slit S through the sample chamber 4. The above constitutes the main body of the spectrophotometer.

FIG. 1A shows a state in which the above-mentioned apparatus is used as a liquid chromatograph detector. In this case, a flow cell F is placed in the sample chamber 4. The flow cell F is connected to a liquid chromatograph (not shown), the effluent of the liquid chromatograph is circulated as indicated by an arrow, and the light from the light source 5 is made to enter the spectroscope 1 through this flow cell.

FIG. 1B shows the measurement of transmitted light of a sample at an arbitrary place or a sample which is not allowed to enter the sample chamber 4 by the above-mentioned apparatus, or the measurement of a luminous body which cannot be placed at an arbitrary place or in the sample chamber at the same time. This shows a case where spectroscopic measurement of light is performed. H1 is an optical fiber holder, a block of a size that can be set in the sample chamber 4, into which an optical fiber FX1 is inserted from the side of the block in a direction orthogonal to the optical axis X of the spectroscope 1, and the light emitting end of the block is inside the spectroscope. It faces the condenser mirror M1 arranged at an angle of 45 ° on the optical axis X, and the opening of the block from this mirror toward the spectroscope slit is an opening. The light incident end of the optical fiber FX1 is opposed to the DUT B placed at an appropriate position. The device under test B is illuminated by a light source 5 'through an appropriate optical system (optical fiber F3 in the figure) so that the light transmitted through the device under test is incident on the light incident end of the optical fiber. When the luminous body B 'is used as the object to be measured, the emission spectrum can be measured. As the luminous body, there are a spark of spark discharge and a plasma flame, and emission spectroscopy can be performed using them. There is a fluorescent substance as a luminous body, and a fluorescent spectrum can be measured by exciting from a side with an appropriate light source.

FIG. 1C shows a case where the above-described apparatus is used for measuring the reflected light of a sample. The optical fiber holder H2 used in this case has two optical fiber FX in the block.
Use the one that holds FX2. This holder block can be installed in the sample chamber 4 with the same outer shape as the holder H1 in FIG. 1B. The holder block has openings on both sides in the optical axis X direction of the spectroscope 1, and two L-shaped passages are formed in the block from the respective openings to two openings on one side of the block. One end of each of optical fibers FX1 and FX2 is inserted and fixed in the two openings of
Condensing mirrors M1 and M2 are arranged at the corners of the character-shaped passage at an inclination of 45 °. When this optical fiber holder H2 is used, the light of the light source 5 is transmitted through the optical fiber FX1 via M1.
And irradiates the sample B out of the other end of the optical fiber. The reflected light from the sample B enters one end of the optical fiber FX2, and the holder H2
The light exits from the inner end and is condensed on the slit S of the spectroscope 1 by the condenser mirror M2, and the reflectance of the sample B is measured.

FIG. 2 shows details of the optical fiber holder H1. An L-shaped passage L is provided in the holder block HB. One opening of the passage L faces the spectroscope 1, and one end of the optical fiber FX1 is inserted into the other opening and fixed with a screw T. K is optical fiber FX1
Is an outer tube. At the corner of the L-shaped passage L, the condenser mirror M1 is 45
゜ It is fixed by tilting. A mounting plate HP is screwed to the side of the block HB from which the optical fibers are drawn.

FIG. 3 shows a configuration in which the optical fiber holder H1 is installed in the sample chamber 4 of the spectroscope. If the block HB is inserted into the window 41 on the side surface of the sample chamber 4 and the mounting plate is fixed to the side wall of the sample chamber with the holder fixing screw Tf, the optical fiber holder is fitted by fitting the outer shape of the holder block HB to the window 41.
H1 is positioned and attached to the sample chamber 4. The mounting structure of the holder H2 to the sample chamber is the same. FIG. 4 shows a flow cell F. The flow cell F also has a through hole in the optical axis direction of the spectroscope 1 in the same block FB as the holder block of the optical fiber holder, and both ends thereof are closed with a transparent body FG.
In and outflow channel Ex are opened, the block FB is inserted into the window 41 of the sample chamber 4, and the mounting plate FP is fixed to the sample chamber 4 with the fixing screw Tf.
By fixing to the side surface, the flow cell F is positioned and mounted in the sample chamber 4.

(Effect of the Invention) Since the spectrophotometer of the present invention uses a one-dimensional image sensor as a light detecting element, it can measure the entire spectral spectrum at a time. The liquid chromatograph detecting apparatus can be obtained by replacing an adapter attached to the sample chamber. Or various spectroscopic measurements using an optical fiber to introduce light into the spectrometer, and it is economical to use one apparatus for various applications.

[Brief description of the drawings]

FIG. 1A is a plan view showing a state in which the apparatus is used as a liquid chromatograph detector of one embodiment of the present invention, FIG. 1B is a plan view showing a measurement using the optical fiber of the embodiment, FIG. FIG. C is a plan view of another form of measurement using an optical fiber in the embodiment, FIG. 2 is a horizontal sectional view of the optical fiber holder, and FIG. 3 is a mounting structure of the optical fiber holder in a spectroscope sample chamber. Perspective view of the fourth
The figure is a horizontal sectional view of the flow cell in FIG. 1A. DESCRIPTION OF SYMBOLS 1 ... Spectroscope, 2 ... Signal processing circuit, 3 ... Shutter, 4 ... Sample chamber, 5 ... Light source, 6 ... Condensing optical type, D
…… Photodiode array, F …… Flow cells FX1, F
X2: Optical fiber, H1, H2: Optical fiber holder, B, B ': Object to be measured, M1, M2: Condensing mirror.

Claims (1)

(57) [Claims] 1. A spectroscope for forming a spectrum image on a one-dimensional imaging device, a light source attached to the spectroscope,
It has a plurality of types of adapters that can be exchangeably attached to the sample chamber of the spectrometer, and these adapters hold a flow cell through which the sample liquid flows, light from the light source transmits, and enters the spectrometer. One, an optical fiber holder holding an optical fiber that guides light from a light source at an arbitrary position to the spectroscope, holding two optical fibers, making the light of the light source incident on one optical fiber, and the other There are three types of optical fiber holders that allow light incident from one end of an optical fiber to enter the spectroscope, and each adapter is a block of a rectangular parallelepiped, in which a predetermined optical configuration is embedded and configured. It has external dimensions that fit the window of the sample chamber, and there is a flange-shaped mounting plate on the outer end face of the block,
When the adapter is inserted through the window of the sample chamber, the position of the adapter in the sample chamber is determined by the fitting of the outer shape to the window and the contact of the mounting plate with the outer surface of the sample chamber. Spectrophotometer.