JP2000046730A - Optical rotation measurement method, concentration determination method, concentration control method, and polarimeter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive small and highly reliable polarimeter suitable for a case where a sample sample has a large optical rotation angle or a case where the concentration of the sample is continuously monitored. . An optical rotation measurement method for compensating optical rotation caused by a test sample containing an optically rotating substance by rotating a vibration surface of light and calculating an optical rotation angle of the test sample based on the compensation value. The transmission axis of the analyzer is tilted in advance with respect to the normal line of the vibration plane of the light to be incident on the test sample in anticipation of the optical rotation caused by the test sample.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical rotation measurement used for identification of a solute in a solution, purity test, concentration determination, and the like. For example, it measures the concentration of an aqueous solution of fructose, sucrose, glucose, etc. Applicable to refractometer.
The present invention also relates to a method for determining the concentration of a solution and a method for controlling the concentration using the optical rotation measurement method.

[0002]

2. Description of the Related Art An example of a conventional polarimeter is shown in FIG. The light source 41 composed of a sodium lamp, a band-pass filter, a lens, a slit, and the like projects substantially parallel light composed of a sodium D line having a wavelength of 589 nm. The polarizer 42 transmits only a component having a specific vibration surface among the projection light of the light source 41. The sample cell 43 holding the test sample has a pair of transparent transmission surfaces facing each other, and the light source 4
1 is arranged so that the light transmitted therethrough passes through the inside.
The linear analyzer 44 transmits only a component having a specific vibration surface out of the light transmitted through the sample cell 43. Here, the relative angle Θ between the transmission axis of the polarizer 42 and the transmission axis of the linear analyzer 44 is fixed to π / 2. The optical sensor 45 detects substantially parallel light transmitted through the linear analyzer 44. The light modulator 46 modulates and controls the vibration surface of the light projected from the light source 41 based on the modulation signal output from the signal generator 50 and the control signal output from the computer 49. The optical modulator 46 is driven by a driver 47. The lock-in amplifier 48 performs phase-sensitive detection on the output signal of the optical sensor 45 using the modulated signal output from the signal generator 50 as a reference signal. The computer 49 determines the sample cell 43 based on the control signal and the output signal of the lock-in amplifier 48.
The angle of rotation of the test sample contained in the sample is calculated.

The principle of this conventional polarimeter will be described below. The light modulator 46 is projected from the light source 41 and the polarizer 4
2 is modulated with amplitude = δ and angular frequency = ω. At this time, the intensity I of the light that reaches the optical sensor 45 is expressed by Expression (1).

I = T × I ₀ × {cos [Θ−α + β + δ × sin (ω × t)]} ² (1) where: T: transmittance of the test sample I ₀ : light incident on the test sample Intensity ：: Relative angle between the transmission axis of polarizer 42 and the transmission axis of linear analyzer 44 α: Optical rotation angle due to test sample β: Rotation angle of light by optical modulator 49 t: Time The sample cell 43 and the linear detector The transmission loss and reference loss of the photon 44 are ignored.

Here, since the relative angle 透過 between the transmission axis of the polarizer 42 and the transmission axis of the linear analyzer 44 is π / 2, the following equation (2) is derived from the equation (1). I = T × I ₀ × {sin [β−α + δ × sin (ω × t)]} ² (2) When β−α = 0, that is, when the rotation angle of the optical modulator 46 is When compensation is made, equation (2) is represented by equation (3) below.

I = (1/2) × T × I ₀ × {1-cos [2 × δ × sin (ω × t)]} = (1/2) × T × I ₀ × {1- [J ₀ (2 × δ) + 2 × J ₂ (2 × δ) × cos (2 × ω × t) +...] (3) where J _n (x) is an n-order Bessel function. .

If the optical rotation angle and the amplitude of modulation by the test sample are small, that is, | β−α | ≪1 and δ≪1, equation (3) is approximated to equation (4) below.

I ≒ T × I ₀ × (β−α + δ × sin (ω × t)) ² = T × I ₀ × ｛(β−α) ² + 2 × (β−α) × δ × sin (ω × t) + [δ × sin (ω × t)] P ² ＝= T × I ₀ × ｛(β−α) ² + 2 × (β−α) × δ × sin (ω × t) + ｛δ ² / 2 × [1-cos (2 × ω × t)]｝｝ (4)

From this, it can be seen that the output signal I of the optical sensor 45 includes signal components of angular frequency 0 (DC), ω, and 2 × ω. When this I is phase-sensitive detected by the lock-in amplifier 48 using the modulated signal as a reference signal,
Angular frequency ω component, that is, S represented by the following equation (5)
Can be taken out. S = T × I ₀ × 2 × (β−α) × δ (5) This S becomes zero only when β = α. This point is the extinction point. By rotating the oscillating surface of light by the optical modulator 46, that is, by sweeping β, β when S becomes zero
Is the optical rotation angle α. The same is true for the case of formula (3),
When I is phase-sensitive detected, when β = α, the optical sensor 45
Output signal becomes zero. As described above, by modulating the angle of the oscillating surface of light, only the signal of the modulation frequency component can be separated from noise such as light source intensity, fluctuation of power supply, and radiation, and selectively extracted. / N can be obtained. From this S, the extinction point can be accurately found, and the optical rotation angle α can be measured with high accuracy. At the same time, sweeping the angle of the vibrating surface eliminates the need for a large-scale device.

However, the above-described method has the following problems. Conventionally, the relative angle の between the transmission axes of the polarizer 42 and the linear analyzer 44 is fixed to π / 2. Therefore, the rotation angle α due to the test sample is large and β
Is small, that is, when | β−α | is large, I becomes large as is clear from the equation (2). If I becomes too large, the output of the optical sensor 45 or the output of the preamplifier thereof is saturated, and the modulation component δ cannot be detected. As a result, the output signal of the lock-in amplifier 48 is fixed to zero, and the extinction point cannot be found.
In some cases, the optical rotation angle cannot be measured. Even if the angle of the light oscillating surface is not modulated and the lock-in amplifier 48 is not used, if I becomes saturated, it is necessary to increase or decrease β in order to detect the extinction point. The judgment cannot be made. For example, when it is necessary to continuously monitor the concentration of the test sample, it is extremely inconvenient if the output of the optical sensor 45 or the like is saturated and the above situation occurs. Either reduce the intensity of the light source 41 or
If the sensitivity of No. 5 or the gain of the preamplifier thereof is reduced, saturation of I can be prevented, but this reduces the S / N of the signal, resulting in reduced measurement accuracy.

Further, since the polarization direction of light is rotated by an optical modulator 46 such as a Faraday cell, the current supplied to the optical modulator 46 increases as β increases. As a result, it is necessary to increase the capacity of the driver. Further, when a large current is supplied, the heat generation of the optical modulator 46 increases, so that cooling may be required in some cases. Therefore,
The size of the polarimeter had to be large.

[0012]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and has a small size suitable for the case where the rotation angle of the test sample is large or the case where the concentration of the test sample is continuously monitored. It is an object to provide a highly reliable polarimeter at a low cost.

[0013]

According to the present invention, there is provided a method for measuring an optical rotation in which a rotation angle caused by an optically rotating substance in a test sample is determined using a linear analyzer. In anticipation of this, the transmission axis of the linear analyzer is tilted in advance with respect to the normal to the vibration plane of the polarized light to be incident on the test sample. This method includes, for example, a method of obtaining the optical rotation of a test sample from the intensity of light transmitted through a linear analyzer arranged downstream of the test sample, and a method of compensating by applying a magnetic field to the test sample. This is useful for a method of canceling the optical rotation due to the optically rotating substance in the sample by the optical Faraday effect and obtaining the optical rotation angle from the strength of the magnetic field at this time. When a polarization splitting element is used instead of a linear analyzer, the axis where the intensity of light transmitted therethrough and the intensity of light reflected therefrom are equal to the oscillation plane of the optical rotation that is incident on the test sample. And tilt it.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The optical rotation measuring method according to the present invention comprises the steps of irradiating a test sample with light having a known vibration surface and detecting the vibration surface of the light transmitted through the test sample using a linear analyzer. Is a method for measuring the optical rotation angle of light by the test sample, wherein the transmission axis of the linear analyzer is fixed at a predetermined inclination angle with respect to the normal line of the vibration plane of the light to be incident on the test sample. Then, the optical rotation angle caused by the test sample is calculated using the intensity and the inclination angle of the light transmitted through the linear analyzer.

According to another optical rotation measuring method of the present invention, light having a known vibration surface is incident on a test sample, and the vibration surface of the light transmitted through the test sample is detected using a linear analyzer. An optical rotation measurement method for determining an optical rotation angle of light by a test sample, wherein a transmission axis of the linear analyzer is fixed at a predetermined inclination angle with respect to a normal line of a vibration surface of light to be incident on the test sample. By rotating the vibration plane of the light, the rotation of light caused by the test sample is compensated, and the angle of rotation caused by the test sample is calculated using the compensation value and the predetermined angle. For example,
The optical rotator and the linear analyzer are rotated from a so-called orthogonal Nicols state, and a part of the optical rotation angle appearing by the test sample is compensated in advance by the rotation angle. This makes it possible to reduce the capacity of the means for rotating the light vibrating surface, so that the device can be downsized.

As for the angle between the transmission axis of the linear analyzer and the normal to the vibration plane of the light incident on the test sample, the maximum and minimum values of the optical rotation angle when the light passes through the test sample are known. Alternatively, if it is predictable, it is desirable to set them within a range having these ends. Preferably, the optical rotation angle indicated by the reference sample when the reference sample is used as the test sample is set to this angle. This makes it possible to compare the density of the optical rotation substance concentration of the test sample with the optical rotation substance concentration of the reference sample based on the sign of the compensation value. Such a method is also useful when preparing a solution having the same optical rotation substance concentration as the reference sample while adjusting the optical rotation substance concentration of the test sample.

Still another optical rotation measurement method of the present invention is to apply light having a known vibration surface to a test sample, transmit light transmitted through the test sample, and transmit only a component having a specific vibration surface, and Rotation caused by the test sample using the intensity of light reflected from the polarization separation element and the intensity of light transmitted through the polarization separation element by making the polarization separation element reflect only a component having a vibration plane perpendicular to the incident light. An optical rotation measurement method for determining an angle,
The polarization separation element is fixed such that an axis at which the intensity of light reflected from the incident light and the intensity of light transmitted therethrough are equal to each other is inclined with respect to the vibration plane of the light incident on the test sample. When a polarization splitter is used instead of a linear analyzer as an analyzer, the intensity of reflected light and the intensity of transmitted light are compared, and the optical rotation angle is determined based on when both become equal. At this time, the intensity of the light reflected from the polarization separation element and the polarization separation element are set so that the polarization separation element has the maximum value and the minimum value of the optical rotation angle predicted when light passes through the test sample at both ends. It is desirable to arrange them so that the intensities of the light passing through them are equal. Further, when a reference sample having a predetermined optical rotation angle is used as the reference sample, the intensity of light reflected from the polarization separation element and the intensity of light transmitted through the polarization separation element may be equal.

The reference sample as described above has an optical rotation angle of
It is desirable to set the rotation angle to be an intermediate value between the maximum value and the minimum value of the optical rotation angle predicted when the test sample to be measured is used. In this case, similarly, the density of the optical rotation substance concentration of the test sample is determined by the sign of the difference between the intensity of light reflected from the polarization separation element and the intensity of light transmitted through the polarization separation element to the optical rotation substance concentration of the reference sample. Can be compared.

The polarimeter of the present invention comprises a monochromatic light source that projects substantially parallel light, a polarizer that transmits only a component having a specific vibration surface of the substantially parallel light, and a substantially parallel light that has passed through the polarizer. A sample cell that holds a test sample so that it passes through the test sample, a linear analyzer that transmits only components having a vibration surface in a specific direction out of substantially parallel light that has passed through the test sample, and a linear analyzer that passes through the linear analyzer An optical sensor for detecting the substantially parallel light is provided, and the transmission axis of the polarizer is minimized so that the substantially parallel light passing through the linear analyzer becomes minimum when a reference sample having a predetermined rotation angle is used as a test sample. And the relative angle of the transmission axis of the linear analyzer is fixed.

In a preferred embodiment of the polarimeter according to the invention,
A light modulating means for rotating a vibrating surface of substantially parallel light passing through the polarizer and entering the test sample; a light modulation controlling means for outputting a control signal to the light modulating means; a control signal and an output of the light sensor Further comprising calculating means for calculating the angle of rotation of the test sample based on the signal, wherein the relative angle between the transmission axis of the polarizer and the transmission axis of the linear analyzer is such that the reference sample is used as the test sample and the light modulation means The setting is made so that the substantially parallel light transmitted through the linear analyzer when the vibration plane of the substantially parallel light is not rotated is minimized. In another preferred embodiment of the polarimeter of the present invention, a magnetic field applying means for applying a magnetic field to the test sample, a magnetic field control means for outputting a control signal to the magnetic field applying means, and a control signal and an output signal of the optical sensor Calculating means for calculating the angle of rotation of the test sample, wherein the relative angle between the transmission axis of the polarizer and the transmission axis of the linear analyzer is linear when the reference sample is used as the test sample and no magnetic field is applied. The setting is such that substantially parallel light transmitted through the photon is minimized. The polarized substantially parallel light passes through a light modulating means such as a Faraday cell before being incident on the test sample, and its vibration surface is rotated. Further, a magnetic field may be applied to the test sample to rotate the vibration plane of the substantially parallel light propagating in the test sample.

Further, a signal generator for outputting a modulation signal for modulating the control signal, and a lock-in amplifier for phase-sensitive detection of the output signal of the optical sensor using the modulation signal as a reference signal are provided. If the optical rotation angle of the test sample is calculated based on the output signal of the in-amplifier, the optical rotation can be measured more accurately. Further, another lock-in amplifier for performing phase-sensitive detection using the output signal of the optical sensor as a signal having a frequency twice as high as the modulation signal as a reference signal is further provided. If the output signal of the in-amplifier is standardized, the optical rotation can be measured with higher accuracy. The relative angle between the transmission axis of the polarizer and the transmission axis of the linear analyzer is set so that, for example, the output signal of the lock-in amplifier becomes zero.

Still another polarimeter of the present invention is a monochromatic light source that projects substantially parallel light, a polarizer that transmits only a component having a specific vibration surface of the substantially parallel light, and a substantially parallel light that transmits the polarizer. A sample cell that holds the test sample so that light transmits through the test sample, and has a vibration surface that transmits only a component having a specific vibration surface among substantially parallel light transmitted through the test sample and is perpendicular to the component. A polarization separation element that reflects only the component, a first optical sensor that detects substantially parallel light transmitted through the polarization separation element, a second optical sensor that detects substantially parallel light reflected from the polarization separation element, Calculating means for calculating an optical rotation angle due to the test sample based on a difference between output signals of the second optical sensor, wherein a relative angle between a transmission axis of the polarizer and a transmission axis of the polarization separation element is a predetermined optical rotation angle When a reference sample showing The intensity of the substantially parallel beam reflected intensity of substantially parallel light transmitted through the separation element is fixed to be equal.

In a preferred embodiment of the polarimeter according to the invention,
Light modulation means for modulating the intensity of substantially parallel light to be incident on the test sample, and a lock-in amplifier for phase-sensitive detection of the difference between the output signals of the first and second optical sensors using the modulated signal as a reference signal; and The calculating means calculates the optical rotation angle of the test sample based on the output signal of the lock-in amplifier. In another preferred embodiment of the polarimeter of the present invention, by adjusting the relative angle so that the output signal of the lock-in amplifier becomes zero, the intensity of the substantially parallel light transmitted and reflected by the polarization separation element becomes equal. The relative angle between the polarizer and the polarization splitter is set.

The optical rotation measurement method and the polarimeter as described above are particularly useful when used for inspection, management and control of the concentration of the optical rotation substance in a solution in a food, a pharmaceutical production plant, a medical treatment site or the like. This is extremely effective because it is possible. Furthermore, since a sampling operation is unnecessary and measurement without contact with a reagent or the like is possible, there is no possibility of contamination or the like, and the safety is extremely high. In addition, it is highly practical because of its features such as high reliability, small size, and low price.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

Embodiment 1 FIG. 1 schematically shows the configuration of a polarimeter according to this embodiment. The semiconductor laser module 1 projects substantially parallel light having a wavelength of 780 nm and an intensity of 3.0 mW. The polarizer 3 transmits only a specific polarized light component having a vibration plane coincident with the transmission axis of the light projected by the semiconductor laser module 1, for example, only a component having a vibration plane parallel to the paper surface. A Faraday cell 4 is disposed downstream of the polarizer 3. The Faraday cell 4 includes a light-transmitting core material made of, for example, flint glass, and a solenoid coil that generates a magnetic field in a traveling direction of light propagating through the core material.

The Faraday cell driver 9 transmits a control signal for generating a magnetic field to the Faraday cell 4 and a modulation signal for modulating the generated magnetic field to the Faraday cell 4.
Output to The Faraday cell 4 generates a magnetic field according to a signal from the Faraday cell driver 9 and rotates the vibration surface of the transmitted light by the optical Faraday effect. A sample cell 5 containing a test sample is projected from the semiconductor laser module 1, and the polarizer 3 and the Faraday cell 4
Are arranged so that the light transmitted through is transmitted through the inside. The substantial optical path length of the sample cell 5 is 50 mm.
The linear analyzer 6 is rotatable about an axis along the traveling direction of the projection light, and the angle thereof can be set to an arbitrary value. The optical sensor 7 detects light transmitted through the linear analyzer 6.

The preamplifier 8 amplifies the output of the optical sensor 7. The signal generator 10 outputs a modulation signal to the Faraday cell driver 9. The lock-in amplifier 11 performs phase-sensitive detection on the output signal of the preamplifier 8 using the modulated signal output to the Faraday cell 4 as a reference signal. The computer 12 outputs a control signal to the Faraday cell driver 9 so that the output of the lock-in amplifier 11 becomes zero.
In the present optical rotation meter, the optical rotation angle is calculated based on the control signal when the output of the lock-in amplifier 11 becomes zero, that is, the magnitude of the compensation current. With the above configuration, an accuracy of about 10 ^-3 degrees is achieved.

Actually, various glucose aqueous solutions were prepared, and their optical rotation angles were measured as follows. A plurality of glucose aqueous solutions having a concentration of about 5000 mg / dl were prepared. The concentration of the actually obtained aqueous glucose solution is 49
It varied in the range of 50 to 5050 mg / dl. In addition,
These average concentrations are the target concentration of 5000 mg / dl.
Met. First, the Faraday cell 4 has an amplitude of 0.00
At 1A, only a modulation signal having a frequency of 1.3 kHz was output, and the control signal was fixed to zero. Then, an aqueous glucose solution confirmed to have a target concentration of 5000 mg / dl was injected into the sample cell 5, and the angle of the linear analyzer 6 was set so that the output of the lock-in amplifier 11 became zero. Next, 4950 mg / dl which is the lower limit of the concentration
Then, an aqueous glucose solution of 5050 mg / dl, which is the upper limit, was placed in each sample cell 5, and it was confirmed that the output of the optical sensor 7, the output of the preamplifier 8, and the output of the lock-in amplifier 11 were not saturated. Here, it is desirable to adjust the gain of the preamplifier 8 or the lock-in amplifier 11 so that the absolute value of the output of the lock-in amplifier 11 is maximized.

As described above, after the angle of the linear analyzer 6 is initially set and each gain is adjusted, the density is set to 4950, 4960, 4970, 4980, 499 for preparing a calibration curve.
0, 5000, 5010, 5020, 5030, 504
0 and 5050 mg / dl aqueous glucose solutions were prepared, and the compensation current was measured when these were used as test samples. The result is shown by a black circle in FIG. From FIG.
It can be seen that the glucose concentration and the compensation current have a high linear relationship. The straight line in the figure is a regression line calculated from the obtained compensation current amount. According to this straight line, the concentration 5000 mg
The compensation current for a glucose aqueous solution having a concentration of 4950 mg / dl is -0.05 A, and the compensation current for a glucose aqueous solution having a concentration of 5050 mg / dl is 0.05 A. Using this regression line as a calibration curve, 4950 to 5050 mg / d
The concentration of the aqueous glucose solution in the range of 1 can be measured. In addition, for example, when determining the density of a sample using 5000 mg / dl as a boundary value, as in the present embodiment, 5
When a 000 mg / dl aqueous solution is used, the linear analyzer 6
When the rotation angle of the linear analyzer 6 is set so that the intensity of light transmitted through the sample becomes minimum, the density of the test sample can be determined based on whether the compensation current is positive or negative.

When creating a calibration curve,
It is not necessary to directly determine the point where the output signal of the lock-in amplifier 11 becomes zero. It is also possible to measure the compensation current at an arbitrary point while sweeping the current supplied to the Faraday cell 4, and to obtain the compensation current by interpolation or extrapolation from the obtained regression line. Also in this case, the angle of the linear analyzer 6 is set in the same manner as described above. However, if the upper and lower limits of the concentration of the test sample to be measured are known or predictable, a sample having these concentrations at the boundary value is used, and when the sweep current supplied to the Faraday cell 4 is the maximum and minimum, Output of optical sensor 7, output of preamplifier 8, and lock-in amplifier 11
It is desirable to confirm that the output is not saturated. More preferably, the gain of the preamplifier 8 or the lock-in amplifier 11 is adjusted so that the absolute value of the output of the lock-in amplifier 11 is maximized.

As described above, according to the present embodiment, even when a solution having a high concentration is used as a test sample, the optical rotation angle can be continuously and accurately measured. When the accuracy is not so required, the modulation current is not supplied to the Faraday cell 4, that is, the lock-in amplifier 11 is not used,
While checking the output signal of the preamplifier 8, the current supplied to the Faraday cell 4 when the output signal becomes zero may be used as the compensation current. In the case where further accuracy is not required, the optical rotation angle may be obtained only from the output signal of the preamplifier 8 without using the Faraday cell 4. In this case, in equation (1), I corresponds to the output signal of the preamplifier 8,
β = 0, δ = 0 and Θ = π / 2 + (initial setting angle), and the optical rotation angle α can be calculated based on the equation (1).

Embodiment 2 In this embodiment, an example of continuously measuring the concentration of a test sample will be described. In this embodiment, an aqueous sucrose solution is prepared while controlling its concentration. FIG. 3 schematically shows an apparatus for producing an aqueous sucrose solution used in this embodiment. In this manufacturing apparatus, a polarimeter similar to that used in Example 1 is used. However, instead of the Faraday cell 4, light is rotated by a solenoid coil 13a provided directly on the sample cell 13. In the figure, the same components as those used in the first embodiment are denoted by the same reference numerals.

The sample cell 13 has a cylindrical hollow portion for containing a test sample. The hollow portion is designed to transmit light in the axial direction, and has a substantial optical path length of 50 m.
m. The solenoid coil 13a is connected to the sample cell 1
A magnetic field is applied to the test sample accommodated in 3 in the light propagation direction. The coil driver 14 includes a solenoid coil 13a.
, And controls the solenoid coil 13a while modulating the vibration surface of the substantially parallel light by the optical Faraday effect, similarly to the Faraday cell 4 used in the first embodiment. Note that the coil driver 14 used here has a so-called unipolarity in which the direction of current supply is constant, unlike the Faraday cell driver 9. The basic principle of the method of measuring the optical rotation angle by the Faraday effect of the test sample itself is described in JP-A-9-145605.

In this embodiment, the concentration is 10,000 mg / dl.
Concentration 1100 using sucrose solution stock solution and sucrose powder
A method for producing a 0 mg / dl sucrose aqueous solution will be described. Pre-prepared concentration 10000mg / d
1 of the sucrose aqueous solution is introduced into the adjusting tank 15 through the fluid inlet 19. The sucrose powder is charged into the adjustment tank 15 from the powder charging port 20. Stirring propeller 2
1 stirs the aqueous sucrose solution in the adjustment tank 15. The aqueous sucrose solution in the adjustment tank 15 is supplied to the sample cell 13 through the pipe 16 by the pump 18. The aqueous sucrose solution supplied to the sample cell 13 returns to the adjustment tank 15 through the pipe 17. Computer 12
Outputs a control signal to the coil driver 14 so that the output of the lock-in amplifier 11 becomes zero, as in the first embodiment. Thereby, the optical rotation angle is calculated based on the magnitude of the control signal when the output of the lock-in amplifier 11 becomes zero, that is, the compensation current amount.

While measuring the optical rotation angle, the computer 12 supplies the raw sucrose aqueous solution from the fluid input port 19 and the sucrose powder from the powder input port 20 based on the obtained optical rotation angle. The concentration of the aqueous sucrose solution in the adjustment tank 15 is controlled by adjusting the supply amount. That is, when the concentration of the aqueous sucrose solution in the adjustment tank 15 is lower than the control target concentration, the sucrose powder is charged through the powder inlet 20 to increase the concentration of the aqueous sucrose solution in the adjustment tank 15.
When the concentration is higher than the control target concentration, the sucrose aqueous solution is supplied from the fluid supply port 19 to lower the concentration of the sucrose aqueous solution in the adjustment tank 15. In this way, when it is confirmed that the concentration of the aqueous sucrose solution in the adjustment tank 15 has reached the control target concentration, the valve 23 is opened, and the aqueous sucrose solution in the adjustment tank 15 is supplied to the next step through the pipe 22. I do.

Hereinafter, the procedure for measuring the optical rotation angle in the present manufacturing apparatus will be described. First, the amplitude of the modulation signal supplied to the coil driver 14 is set to 0.1 A, the frequency is set to 270 Hz, and the control signal is made constant at the amplitude of the modulation signal, that is, 0.1 A. This is because the coil driver 14 is unipolar, so that the control signal cannot be set smaller than the amplitude of the modulation signal in order to maintain the modulation degree. Concentration 1000
Adjustment tank 1 with only 0 mg / dl sucrose raw material aqueous solution
The angle of the linear analyzer 6 is set so that the output of the lock-in amplifier 11 becomes zero when the condition of 5 is satisfied. next,
The sucrose powder is put into the adjusting tank 15 and the concentration is adjusted to 120.
The output is increased to 00 mg / dl, and it is confirmed that the output of the optical sensor 7, the output of the preamplifier 8, and the output of the lock-in amplifier 11 are not saturated. Here, desirably, the gain of the preamplifier 8 or the lock-in amplifier 11 is adjusted so that the absolute value of the output of the lock-in amplifier 11 is maximized.

As described above, after the angles of the linear analyzer 6 are initially set and the respective gains are adjusted, the adjusting tank 15 is set to a concentration of 10,000, 11000 and 12000 mg / d.
1 sucrose aqueous solution, and the compensation current was measured for each. This result is shown by a black circle in FIG. A regression line represented by a straight line in the figure is obtained from the obtained compensation current amount. According to the obtained regression line, if the compensation current is controlled to be 2.1 A, an aqueous sucrose solution having a control target concentration of 11000 mg / dl can be produced. Further, according to the obtained regression line, the compensation current amount for the aqueous sucrose solution having a concentration of 9950 mg / dl becomes zero. That is, when the control signal is zero and the concentration is 9950 mg / dl, the light transmitted through the linear
Is set.

According to the present embodiment, the absolute value of the compensation current can be reduced by inclining the transmission axis of the linear analyzer in advance with respect to the normal to the vibration plane of the light to be incident on the test sample. it can. In a polarimeter similar to that used in the present embodiment, as in the conventional optical rotation measurement, when the concentration is 0, that is, when pure water is put, a straight line is set so that the light transmitted through the linear analyzer 6 is minimized. If the angle of the analyzer 6 is set, the compensation current reaches about 20 A, so that it is necessary to increase the capacity of the coil driver, and at the same time, it is necessary to take measures against heat generation of the coil. As a result, the size of the apparatus is also increased.
On the other hand, according to the present embodiment, the compensation current amount may be small, and the capacity of the coil driver can be reduced. Therefore, the optical rotation angle (that is, the optical rotation) of the solution having a high concentration can be continuously measured with high accuracy using a small apparatus.

Embodiment 3 In this embodiment, as in Embodiment 2, another example of producing an aqueous sucrose solution while controlling its concentration will be described. In this embodiment, two kinds of sucrose aqueous solutions having different concentrations prepared in advance are mixed to produce an aqueous sucrose solution having a concentration of 11000 mg / dl. FIG. 5 shows an outline of an apparatus for producing an aqueous sucrose solution used in this example. In this manufacturing apparatus, a polarimeter similar to that used in Example 2 was used. However, the coil driver 24
Unlike the coil driver 14, is a so-called bipolar that can supply a current in both directions. The coil driver 24
Like the coil driver 14 in the second embodiment, the modulation signal and the control signal are supplied to the solenoid coil 13a of the sample cell 13. In the drawings, the same components as those used in the above embodiment are denoted by the same reference numerals.

A previously prepared concentration of about 10,000 m
The g / dl sucrose aqueous solution is introduced into the adjusting tank 15 through the fluid inlet 19. Similarly, a sucrose aqueous solution having a concentration of about 12000 mg / dl prepared in advance is supplied to the adjustment tank 15 from the fluid supply port 25. Also,
The computer 12 outputs a control signal to the coil driver 24 so that the output of the lock-in amplifier 11 becomes zero. As a result, the magnitude of the control signal at which the output of the lock-in amplifier 11 becomes zero, that is, the amount of compensation current is found, and the optical rotation angle is calculated. Further, the computer 12 adjusts the supply of each stock solution from the fluid inlet 19 and the fluid inlet 25 based on the obtained rotation angle, and
5 to control the concentration of the aqueous sucrose solution. Adjustment tank 15
When it is confirmed that the concentration of the aqueous sucrose solution has reached a predetermined concentration, the valve 23 is opened, and the aqueous sucrose solution in the adjustment tank 15 is supplied to the next step through the pipe 22.

In this embodiment, a density of 1
An apparatus for producing a 1000 mg / dl sucrose aqueous solution will be described. First, no control signal is output to the coil driver 24, and only a modulation signal having an amplitude of 0.1A is output. The angle of the linear analyzer 6 is set so that the output of the lock-in amplifier 11 becomes zero in a state where the adjustment tank 15 is filled with only the sucrose aqueous solution whose concentration has been confirmed to be 10000 mg / dl. Next, the concentration 12
The output of the optical sensor 7, the output of the pre-amplifier 8, and the output of the lock-in amplifier 11 are obtained with either the sucrose aqueous solution confirmed to be 000 mg / dl or 10000 mg / dl and the adjustment tank 15 being filled. Make sure it is not saturated. Here, desirably, the absolute value of the output of the lock-in amplifier 11 is maximized.
The gain of the preamplifier 8 or the lock-in amplifier 10 is adjusted.

As described above, after the angle of the linear analyzer 6 is initially set and each gain is adjusted, the density is set to 10,000, 1
The adjusting tanks 15 were filled with 1000 and 12000 mg / dl sucrose aqueous solutions, respectively, and the compensating current amounts when these were used as test samples were determined. The results are shown by black circles in FIG. In the figure, the straight line is a regression line obtained from the obtained compensation current amount. If this compensation line becomes zero by using this regression line as a calibration curve, the control target concentration 1
A 1000 mg / dl sucrose aqueous solution can be produced.

In this embodiment, the angle of the linear analyzer 6 is set so that the light transmitted through the linear analyzer 6 is minimized when the control signal is zero and the aqueous solution has the control target concentration of 11,000 mg / dl. did. This means that the angle of the linear analyzer 6 is set so as to correspond to the control target density. Therefore, the compensation current may be small near the control target concentration. Normally, during the production, that is, during the measurement of the optical rotation angle, the sucrose concentration of the aqueous solution is in the vicinity of the control target concentration for the longest time, and as a result, the calorific value can be reduced. Furthermore, the highest concentration that the aqueous solution can show (= 12000 m
g / dl) and the angle of the linear analyzer 6 so that the intermediate value between the minimum concentration (= 10000 mg / dl) and the minimum concentration (= 10000 mg / dl) can be set as the maximum, so that the gain of the preamplifier 8 or the lock-in amplifier 11 can be set to the maximum. The measurement accuracy can be maximized. When the accuracy is not so required, no modulation signal is supplied to the solenoid coil 13a, that is, the output signal of the preamplifier 8 is checked without using the lock-in amplifier 11 and the output becomes zero. The control signal output to the solenoid coil 13a may be used as the compensation current. As described above, the polarimeter of the present embodiment is small and can continuously measure the optical rotation angle of a solution having a high concentration with high accuracy. In particular, even during long-time continuous production, the calorific value of the coil is small, so that it can be used more stably than the polarimeter used in the second embodiment.

Embodiment 4 In this embodiment, as in Embodiment 3, another example of producing an aqueous sucrose solution while controlling its concentration will be described. FIG. 7 shows an outline of an apparatus for producing a sucrose aqueous solution according to the present embodiment. In the drawings, the same components as those used in the above embodiment are denoted by the same reference numerals. The sample cell 26 has a cylindrical hollow portion for containing a sample. Light is transmitted through the hollow portion in the axial direction, and its substantial optical path length is 50 mm.
The aqueous sucrose solution in the adjustment tank 15 is supplied to the sample cell 26 through the pipe 16. The aqueous sucrose solution supplied to the sample cell 26 returns to the adjustment tank 15 through the pipe 17. A polarization beam splitter 27 having a polarization splitting function is disposed downstream of the sample cell 26. The polarization beam splitter 27 separates the light transmitted through the sample cell 26 into a specific polarization component. For example, a component having a vibration surface parallel to the paper surface is transmitted, and a component having a vibration surface perpendicular to the paper surface is reflected. The polarizer 28 is rotatable about an axis along the direction of propagation of the incident light. Here, when there is no optical rotation due to the solution in the sample cell 26 and the angle of the transmission axis of the polarizer 28 is set to be 45 degrees inclined from the paper surface, the substantially parallel light transmitted through the polarizing beam splitter 27 and the substantially parallel light reflected are reflected. The light intensity will be equal. Also, the difference between the transmitted light and the reflected light increases according to the angle of rotation of the solution in the sample cell 26. Optical sensor 2
9 and 30 detect these transmitted light and reflected light, respectively. The differential amplifier 31 includes optical sensors 29 and 30
Amplify the output difference. Therefore, the magnitude of the output signal of the differential amplifier 31 corresponds to the magnitude of the optical rotation angle of the solution.

From the fluid inlet 19, a concentration of about 10,000
A stock solution of sucrose aqueous solution of mg / dl is charged into the adjusting tank 15. A concentration of about 12000 mg /
dl of the sucrose aqueous solution stock solution is charged into the adjustment tank 15. The computer 32 controls the concentration of the aqueous sucrose solution in the adjusting tank 15 by adjusting the supply amount of the aqueous sucrose solution from the fluid inlet 19 and the fluid inlet 25 according to the output of the differential amplifier 31. . When it is confirmed that the concentration of the aqueous sucrose solution in the adjustment tank 15 has reached the target concentration,
The valve 23 is opened, and the adjustment tank 1 is
The sucrose aqueous solution in 5 is flowed to the next step.

In this embodiment, the control target density is set to 11000.
The case of setting to mg / dl will be described. First, the angle of the polarizer 28 is set so that the output of the differential amplifier 31 becomes zero in a state where the adjustment tank 15 is filled with only the sucrose aqueous solution confirmed to have a concentration of 10,000 mg / dl. Next, the concentration of 12000 mg /
dl or 10,000 mg / dl, the output of the optical sensors 29 and 30 and the differential amplifier 31
Check that the output of each is not saturated. Here, it is desirable to adjust the gain of the differential amplifier 31 so that the absolute value of the output of the differential amplifier 31 is maximized.

As described above, after the angle of the polarizer 28 is initially set and each gain is adjusted, the densities of 10,000, 11
A calibration curve is prepared using sucrose aqueous solutions of 000 and 12000 mg / dl. The adjustment tank 15 was filled with each of these aqueous solutions, and the output of the differential amplifier 31 was measured. This result is shown by a black circle in FIG. The straight line shown in FIG.
It is a regression line obtained from these measurement data. If the output signal of the differential amplifier 31 is made zero based on this straight line, the control target concentration of 11,000 mg /
dl of sucrose aqueous solution can be produced. In the case of the present embodiment, the output signal of the differential amplifier 31 is zero, and the sucrose concentration of the aqueous solution is the control target concentration, that is, 11,000 mg / d.
At l, the angle of the polarizer 28 was set such that the intensity of light transmitted through the polarization splitting element, that is, the polarization beam splitter 27, was equal to the intensity of reflected light. This means that the initial angle of the polarizer 28 is set so as to correspond to the control target density. As a result, the sign of the output signal of the differential amplifier 31 is inverted with the control target concentration interposed therebetween, so that the computer 32 may control the concentration of the sample based on the sign of the output signal. In particular, the reference control target concentration is set to the highest concentration (= 12000 mg) that the sample can show.
/ Dl) and the intermediate value between the lowest concentration (= 10000 mg / dl), the gain of the differential amplifier 31 can be set to the maximum, so that the accuracy can be maximized. As described above, according to the present embodiment, the optical rotation angle of a solution having a high concentration can be continuously and accurately measured with a small and simple configuration.

Embodiment 5 In this embodiment, still another example of producing an aqueous sucrose solution while controlling its concentration will be described. FIG. 9 shows an outline of an apparatus for producing an aqueous sucrose solution of this embodiment. In the present embodiment, the optical rotation angle of the sample is measured by using the polarizing beam splitter 27 as in the manufacturing apparatus used in the fourth embodiment. In the drawings, the same components as those used in the above embodiment are denoted by the same reference numerals. The optical chopper 33 includes the semiconductor laser module 1 as a light source.
The intensity of the projected substantially parallel light is modulated at a frequency of 270 Hz. The signal generator 34 outputs a modulation signal to the optical chopper 33. The lock-in amplifier 35 includes the optical chopper 3
The output signal of the differential amplifier 31 is subjected to phase sensitive detection using the modulation signal for the reference signal No. 3 as a reference signal.

In this example, as in Example 4, the concentrations were 10000 mg / dl and 12000 mg / dl, respectively.
dl of the sucrose aqueous solution stock solution to a concentration of 11,000.
The case of producing an aqueous sucrose solution of mg / dl will be described. First, the angle of the polarizer 28 is set so that the output of the lock-in amplifier 35 becomes zero while the adjustment tank 15 is filled with only the sucrose aqueous solution whose concentration has been confirmed to be 10000 mg / dl. . Next, in a state where the adjusting tank 15 is filled with the sucrose aqueous solution having a concentration of 10000 mg / dl and the sucrose aqueous solution having a concentration of 12000 mg / dl, the optical sensor 29 and It is confirmed that the output of the differential amplifier 30, the output signal of the differential amplifier 31, and the output signal of the lock-in amplifier 35 are not saturated. Here, desirably, the gain of the differential amplifier 31 or the gain of the lock-in amplifier 35 is adjusted so that the absolute value of the output of the lock-in amplifier 35 is maximized.

As described above, after the angles of the polarizer 28 are initially set and the respective gains are adjusted, the densities of 10,000, 11
A calibration curve is prepared using sucrose aqueous solutions of 000 and 12000 mg / dl. The adjustment tank 15 was filled with each of these aqueous solutions, and the output signal of the lock-in amplifier 35 was measured. The results are shown by black circles in FIG. FIG.
Is a regression line obtained from these measurement data. If this straight line is used as a calibration curve so that the output signal of the lock-in amplifier becomes zero, an aqueous sucrose solution having a concentration of 11000 mg / dl, which is a control target, can be produced. The reference concentration is defined as the highest concentration (= 12000 mg / dl) that the aqueous solution can show, and the lowest concentration (= 10
000 mg / dl), the gain of the differential amplifier 31 or the lock-in amplifier 35 can be set to the maximum, so that the accuracy can be maximized. Further, unlike the fourth embodiment, since modulation is performed by the optical chopper, it is hardly affected by drift, various radiation noises, and the like, and the accuracy is higher. As described above, according to the present embodiment, the optical rotation angle of a solution having a high concentration can be continuously and more accurately measured.

Embodiment 6 FIG. 11 shows an outline of an apparatus for producing an aqueous sucrose solution of this embodiment. In this embodiment, the second embodiment
The same manufacturing apparatus as used in the above is used. In the figure,
The same components as those used in the above embodiment are denoted by the same reference numerals. The lock-in amplifier 36 operates in a so-called 2F mode, and performs a phase-sensitive detection of the output signal of the preamplifier 8 using a signal having a frequency twice as high as the modulation signal of the signal generator 10 as a reference signal. That is, the 2 × ω component in Expression (4) is extracted. The coil driver 37 has an amplitude of 0.0
At 5 A, only a modulation signal having a frequency of 1.3 kHz is supplied to the solenoid coil 13 a of the sample cell 13. The computer 38 calculates the optical rotation angle by normalizing the output signal of the lock-in amplifier 11 with the output signal of the lock-in amplifier 36. This principle is described below.

The output signal of the lock-in amplifier 11 corresponds to S shown in equation (5). When β is fixed as in the present embodiment, if T, I ₀ and δ are constant, S becomes a function of only the optical rotation angle α, so that α can be uniquely calculated from S. However, actually, T changes due to a difference in transmittance of the test sample, a stain on the transmission window of the sample cell, and the like. At the same time, since I ₀ also changes due to fluctuations in the light source intensity, it is impossible to measure the optical rotation angle with high accuracy from only S. Therefore, the lock-in amplifier 36
Use the output signal of Assuming that the output signal of the lock-in amplifier 36 is S ′, the following equation (6) is obtained. If _{S '= T × I 0 ×} δ 2/2 (6) normalized by dividing the equation (5) In this equation (6), then X shown in equation (7) is obtained. X = 4 / δ × (β−α) (7) Since X does not include T and I ₀ , the optical rotation angle α can be determined with high accuracy from this.

A plurality of glucose aqueous solutions having a concentration of about 5000 mg / dl were prepared. The concentration of the actually obtained glucose aqueous solution varied in the range of 4950 to 5050 mg / dl. The average density is 5 which is the target density.
000 mg / dl. First, the sample cell 13
Then, a modulated signal having an amplitude of 0.05 A and a frequency of 1.3 kHz was output. Then, the target is 5000 m
The glucose aqueous solution confirmed to be g / dl was put into the sample cell 13, and the angle of the linear analyzer 6 was set so that the output of the lock-in amplifier 11 became zero. Next, an aqueous glucose solution having a lower limit of 4950 mg / dl or an upper limit of 5050 mg / dl is put into the sample cell 5, and the output of the optical sensor 7, the output of the preamplifier 8, and the output of the lock-in amplifier 11 are saturated. Not sure that. Here, lock-in amplifier 1
1 and the lock-in amplifier 11 so that the absolute value of the output of the lock-in amplifier 36 becomes maximum.
It is desirable to adjust the gain of the lock-in amplifier 36.

As described above, after the angles of the linear analyzer 6 are initially set and the respective gains are adjusted, the concentrations are set to 4950, 4960, 4970, 4980, 499 for preparing a calibration curve.
0, 5000, 5010, 5020, 5030, 504
0, 5050 mg / dl glucose aqueous solution is prepared,
Using these, X shown in equation (7) was determined. This result is shown by a black circle in FIG. The straight line in the figure is a regression line calculated from the obtained measurement data. According to the obtained regression line, X for a glucose aqueous solution having a concentration of 5000 mg / dl becomes zero. In addition, a concentration of 4950 mg / dl
X of the aqueous glucose solution was -1.0 and the concentration was 50.
X for a 50 mg / dl aqueous glucose solution is 1.0
become. (Β-α) becomes zero for an aqueous glucose solution having a concentration of 5000 mg / dl. Here, β is the optical rotation angle when the concentration of the aqueous glucose solution is 5000 mg / dl. The optical rotation angle, that is, the glucose concentration can be measured using the straight line obtained as described above as a calibration curve.

As described above, according to the present embodiment, a magnetic field is applied to the test sample, the magnetic field is modulated, and the modulation frequency component of the output signal of the optical sensor 7 is changed to twice the modulation frequency. By standardizing with, a polarimeter with high accuracy, high reliability, small size and low cost can be realized. Also, the present embodiment
Unlike the second embodiment, the coil driver 37 does not need to control the current supplied to the solenoid coil. Therefore, 100V is applied to the solenoid coil 13a through an appropriate resistor.
, The coil driver 37 can be realized. That is, the solenoid coil 13
a can be modulated at the frequency of the commercial AC power supply. According to the present embodiment, two lock-in amplifiers are required. However, since the coil driver 37 can be greatly simplified, depending on the cost of the coil driver 37 and the lock-in amplifiers 11 and 36, the implementation is not limited. In some cases, a polarimeter can be provided at a lower price than in Example 2. In this embodiment, similarly to the second embodiment, the polarization is modulated by applying a magnetic field to the test sample and using the Faraday effect of the magnetic field. However, the Faraday cell is used as in the first embodiment. Is also good.

[0057]

According to the present invention, the optical rotation angle of a solution having a high concentration can be continuously and accurately measured. In addition, the density of the solution can be easily determined by this method. Therefore, a highly reliable and small polarimeter suitable for continuous optical rotation measurement can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a polarimeter used in one embodiment of the present invention.

FIG. 2 is a characteristic diagram showing the relationship between the concentration of an aqueous glucose solution and the amount of compensation current obtained using a homorotometer.

FIG. 3 is a schematic diagram showing a configuration of an apparatus for producing an aqueous sucrose solution used in another embodiment of the present invention.

FIG. 4 is a characteristic diagram showing the relationship between the concentration of an aqueous glucose solution and the amount of compensation current obtained using a polarimeter of the manufacturing apparatus.

FIG. 5 is a schematic diagram showing a configuration of an apparatus for producing an aqueous sucrose solution used in still another embodiment of the present invention.

FIG. 6 is a characteristic diagram showing the relationship between the concentration of an aqueous glucose solution and the amount of compensation current obtained using a polarimeter of the manufacturing apparatus.

FIG. 7 is a schematic diagram showing a configuration of an apparatus for producing an aqueous sucrose solution used in still another embodiment of the present invention.

FIG. 8 is a characteristic diagram showing a relationship between a concentration of a glucose aqueous solution and an output of a differential amplifier of the manufacturing apparatus.

FIG. 9 is a schematic diagram showing a configuration of an apparatus for producing an aqueous sucrose solution used in still another embodiment of the present invention.

FIG. 10 is a characteristic diagram showing a relationship between a concentration of a sucrose aqueous solution and an output of a lock-in amplifier of the manufacturing apparatus.

FIG. 11 is a schematic diagram showing a configuration of a polarimeter used in still another embodiment of the present invention.

FIG. 12 is a characteristic diagram showing a relationship between the concentration of an aqueous sucrose solution and X.

FIG. 13 is a schematic diagram showing a configuration of a conventional polarimeter.

[Explanation of symbols]

 Reference Signs List 1 semiconductor laser module 3, 28, 42 polarizer 4 Faraday cell 5, 13, 26, 43 sample cell 6, 44 linear analyzer 7, 29, 30, 45 optical sensor 8 preamplifier 9 Faraday cell driver 10, 34, 50 signal Generator 11, 35, 36, 48 Lock-in amplifier 12, 32, 38, 49 Computer 13a Solenoid coil 14, 24, 37 Coil driver 15 Adjustment tank 16, 17, 22 Piping 18 Pump 19, 25 Fluid supply port 20 Powder supply Port 21 Stirring propeller 23 Valve 27 Polarizing beam splitter 31 Differential amplifier 33 Optical chopper 41 Light source 46 Optical modulator 47 Driver

Claims (21)

[Claims] 1. A light having a known vibration surface is incident on a test sample, and the vibration surface of the light transmitted through the test sample is detected using a linear analyzer, whereby the light generated by the test sample is detected. The optical rotation measurement method for determining the optical rotation angle of the linear analyzer, wherein the transmission axis of the linear analyzer is fixed at a predetermined inclination angle with respect to the normal to the vibration plane of the light to be incident on the test sample, the linear analyzer An optical rotation measurement method for calculating an optical rotation angle caused by the test sample using the intensity of the light transmitted through the analyzer and the inclination angle. 2. A method according to claim 1, wherein a light having a known vibration surface is incident on the test sample, and a vibration surface of the light transmitted through the test sample is detected using a linear analyzer. Optical rotation measurement method for determining the optical rotation angle of the linear analyzer, wherein the transmission axis of the linear analyzer is fixed at a predetermined inclination angle with respect to the normal to the vibration plane of the light to be incident on the test sample, Optical rotation measuring method of compensating for the rotation of the light caused by the test sample by rotating the vibration surface of the sample, and calculating the optical rotation angle caused by the test sample using the compensation value and the tilt angle . 3. The optical rotation measurement according to claim 2, wherein the inclination angle is set within a range including both the maximum value and the minimum value of the optical rotation angle predicted when the light passes through the test sample. Method. 4. The optical rotation measurement method according to claim 2, wherein an optical rotation angle indicated by the reference sample when the reference sample is used as the test sample is set to the inclination angle. 5. The method for measuring optical rotation according to claim 4, wherein
A concentration judging method for comparing the density of the optical rotatory substance concentration of the test sample with the optical rotatory substance concentration of the reference sample based on the sign of the compensation value. 6. An optical rotation measurement method according to claim 4,
A concentration control method for adjusting the optical rotation substance concentration of the test sample while comparing the optical rotation substance concentration of the test sample with the optical rotation substance concentration of the reference sample according to the sign of the compensation value. 7. A component having a vibrating surface with a known vibration surface incident on a test sample, and transmitting the light transmitted through the test sample through only a component having a specific vibrating surface and having a vibrating surface perpendicular thereto. Of the light that is reflected by the polarization separation element and the intensity of the light that passes through the polarization separation element to determine the optical rotation angle of the light by the test sample using the polarization rotation element. In the degree measurement method, the polarization separation element, the axis of the intensity of the light transmitted through the light equal to the intensity of the reflected light of the light incident on it, with respect to the vibration surface of the light to be incident on the test sample Optical rotation measurement method that is fixed at an angle. 8. A light reflected from the polarization separation element within a range having both ends of a maximum value and a minimum value of an optical rotation angle predicted when the light passes through the test sample. The optical rotation measurement method according to claim 7, wherein the optical rotation is arranged so that the intensity of the light transmitted through the polarization splitting element is equal to the intensity of the light. 9. The polarizing beam splitter according to claim 1, wherein when a reference sample having a predetermined optical rotation angle is used as the test sample, the intensity of light reflected from the polarizing beam splitter is equal to the intensity of transmitted light. 9. The method for measuring optical rotation according to claim 8, wherein the optical rotation is arranged. 10. The optical rotation according to claim 4, wherein the optical rotation angle of the reference sample is an intermediate value between the maximum value and the minimum value of the optical rotation angle predicted when the light passes through the test sample. Degree measurement method. 11. The optical rotation of the test sample by using the optical rotation measurement method according to claim 9, based on the sign of the difference between the intensity of light reflected from the polarization separation element and the intensity of light transmitted through the polarization separation element. A concentration determination method for comparing the density of the active substance concentration with the optical rotation substance concentration of the reference sample. 12. The optical rotation of the test sample based on the sign of the difference between the intensity of light reflected from the polarization separation element and the intensity of light transmitted through the polarization separation element, using the optical rotation measurement method according to claim 9. A concentration control method for adjusting the optical rotation substance concentration of the test sample while comparing the substance concentration with the optical rotation substance concentration of the reference sample. 13. A test sample comprising: a monochromatic light source for projecting substantially parallel light; a polarizer for transmitting only a component having a specific vibration surface of the substantially parallel light; and a substantially parallel light for passing through the polarizer. A sample cell that holds the test sample so as to transmit light, a linear analyzer that transmits only a component having a vibration surface in a specific direction out of the substantially parallel light that has passed through the test sample, and the linear analyzer. An optical sensor for detecting the substantially parallel light transmitted through the light source, so that the substantially parallel light transmitted through the linear analyzer is minimized when a reference sample having a predetermined rotation angle is used as the test sample. A polarimeter in which the relative angle between the transmission axis of the polarizer and the transmission axis of the linear analyzer is fixed. 14. A light modulating means for rotating a vibrating surface of the substantially parallel light passing through the polarizer and entering the test sample, and a light modulation controlling means for outputting a control signal to the light modulating means. And calculating means for calculating an optical rotation angle of the test sample based on the control signal and the output signal of the optical sensor, wherein the relative angle between the transmission axis of the polarizer and the transmission axis of the linear analyzer is Wherein the reference sample is used for the test sample and the light modulating means is set so that the substantially parallel light passing through the linear analyzer when the vibration surface of the substantially parallel light is not rotated is minimized. Item 13. The polarimeter according to item 13. 15. A magnetic field applying means for applying a magnetic field to the test sample, a magnetic field control means for outputting a control signal to the magnetic field applying means, and the test object based on the control signal and the output signal of the optical sensor. And calculating means for calculating an optical rotation angle by the sample, wherein the relative angle between the transmission axis of the polarizer and the transmission axis of the linear analyzer is such that the reference sample is used for the test sample and the magnetic field is not applied. 14. The polarimeter according to claim 13, wherein the substantially parallel light transmitted through the linear analyzer is set to be minimum. 16. The arithmetic means, further comprising: signal generation means for outputting a modulation signal for modulating the control signal; and a lock-in amplifier for phase-sensitive detection of the output signal of the optical sensor using the modulation signal as a reference signal. The polarimeter according to claim 14 or 15, further comprising: calculating an optical rotation angle of the test sample based on the control signal and an output signal of the lock-in amplifier. 17. A signal generation means for outputting a modulation signal for modulating the control signal, a lock-in amplifier for phase-sensitively detecting an output signal of the optical sensor using the modulation signal as a reference signal, and an output signal of the optical sensor. To the modulation signal 2
A lock-in amplifier for normalization for performing phase-sensitive detection by using a signal of a double frequency as a reference signal, wherein the calculating means standardizes an output signal of the lock-in amplifier with an output signal of the lock-in amplifier for normalization. The polarimeter according to claim 14 or 15, wherein the polarimeter is formed. 18. The relative angle between the transmission axis of the polarizer and the transmission axis of the linear analyzer so that the output signal of the lock-in amplifier becomes zero.
The polarimeter according to 1. 19. A monochromatic light source that projects substantially parallel light, a polarizer that transmits only a component having a specific vibration surface of the substantially parallel light, and a sample that is a sample to be tested. A sample cell that holds the test sample so as to transmit light, and transmits only a component having a specific vibration surface of the substantially parallel light transmitted through the test sample, and only a component that has a vibration surface perpendicular thereto. A first light sensor that detects the substantially parallel light transmitted through the polarization separation element, and a second light sensor that detects the substantially parallel light reflected from the polarization separation element, Calculating means for calculating an optical rotation angle of the test sample based on a difference between output signals of the first and second optical sensors, and a relative angle between a transmission axis of the polarizer and a transmission axis of the polarization separation element. Is a reference test showing a predetermined optical rotation angle. When the sample was used for the test sample,
A polarimeter fixed so that the intensity of the substantially parallel light passing through the polarization splitting element and the intensity of the substantially parallel light reflected therefrom are equal. 20. An optical modulator for modulating the intensity of the substantially parallel light to be incident on the test sample, and an output of the first and second optical sensors using a modulation signal of the optical modulator as a reference signal. 20. The polarimeter according to claim 19, further comprising: a lock-in amplifier that performs phase-sensitive detection of a signal difference, wherein the calculating unit calculates an optical rotation angle of the test sample based on an output signal of the lock-in amplifier. 21. The polarizer such that the relative angles are adjusted so that the output signal of the lock-in amplifier becomes zero, so that the intensities of substantially parallel lights transmitted and reflected by the polarization separation element become equal. 20. The polarimeter according to claim 19, wherein a relative angle between the polarization separation element and the polarization separation element is set.