JP2011106871A - Polarimeter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarimeter which allows a user to intuitively grasp the measurement status by displaying the operating status of the polarimeter. <P>SOLUTION: The polarimeter displays an angle display means section 41 for indicating the rotational angle of an analyzer on a display section. The angle display section displayed on the display section indicates the rotational angle of the analyzer by rotating an arrow pattern 411 during optical rotation measurement. The user intuitively knows the present rotational angle of the analyzer 15 from a change in the arrow pattern 411 in the angle display section 41. The polarimeter indicates the rotational angle of the analyzer in numerical values by a numerical value display section 42. The polarimeter changes the light and shade within a circular pattern 413 in accordance with the amount of light received of light passed through the analyzer. This allows an intuitive knowing of the progress of the optical rotation measurement. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a polarimeter that measures the optical rotation of a substance.

  Optical rotation is a property of a substance that rotates the polarization plane of incident linearly polarized light, and the angle at which the polarization plane rotates when linearly polarized light is incident on a material having optical rotation is called optical rotation. Since the optical rotation per unit substance amount is a value inherent to the substance, the concentration of the substance in the solution can be measured by measuring the optical rotation of the solution. The method of measuring the concentration of a solution using the optical rotation is superior to the method of using light absorption in that the concentration of a substance that does not absorb light can be measured. In addition, a substance having optical rotatory power generally includes a pair of optical isomerisms of a D-form showing dextrorotation that rotates a polarization plane around a right-handed screw and an L-form showing left-handed rotation that rotates a polarization plane around a left-handed screw. There is a body. By measuring the optical rotation of a substance having a fixed concentration, the ratio of D-form and L-form contained in the substance can be determined.

  A polarimeter that measures the optical rotation of a substance uses a polarizer to convert the light from the light source into linearly polarized light, and the linearly polarized light is incident on the sample solution in which the substance whose optical rotation is to be measured is dissolved, and passes through the sample solution. The linearly polarized light is incident on the analyzer, and the amount of light that has passed through the analyzer is detected. Rotating the analyzer while detecting the amount of light that has passed through the analyzer, and determining the angle of rotation of the analyzer where the amount of light that passes through the analyzer is zero, the angle at which the sample solution has rotated the plane of polarization of the linearly polarized light, That is, the optical rotation of the substance can be obtained. The rotation of the analyzer is feedback controlled based on the detected amount of light that has passed through the analyzer, and the optical rotation is output when the detected amount of light becomes zero.

JP 2002-71464 A

  Patent Document 1 describes an apparatus for calibrating a birefringence measuring device by measuring the birefringence amount of a phase plate whose birefringence amount has been clarified in advance, and the rotation angle of the phase plate at the time of measurement is described. It is described that an angle scale is provided for visually reading. In the conventional polarimeter, the rotation of the analyzer is automatically performed by feedback control, and the optical rotation is output after the measurement is completed. Therefore, there is no rotation scale for visually measuring the rotation angle of the analyzer. For this reason, since the user cannot grasp the measurement status of the polarimeter during the measurement of the optical rotation, it is impossible to estimate the time until the measurement of the optical rotation is completed, and to what degree the optical rotation There is a problem that it is impossible to estimate whether or not

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an optical rotation that allows the user to intuitively understand the measurement status by displaying the operation status of the polarimeter. To provide a total.

  An optical rotation meter according to the present invention includes an analyzer that receives linearly polarized light, a rotating unit that rotates the analyzer, and a light receiving unit that receives light transmitted through the analyzer, and has passed through a sample. Based on the angle by which the analyzer is rotated by the rotating means so that the amount of light received by the light receiving means after the linearly polarized light after passing through the analyzer is minimized, the optical rotation of the sample is determined. The polarimeter to be measured includes an angle display unit that indicates a rotation angle of the analyzer using a figure that rotates in accordance with the rotation of the analyzer by the rotation means.

  In the polarimeter according to the present invention, the angle display unit includes a circle figure, an angle scale along the circle, and a point of rotation of the analyzer around the center point of the circle while pointing to the angle scale. It is configured to display a figure that rotates in response to movement.

  The polarimeter according to the present invention further includes means for indicating the amount of light received by the light receiving means.

  The polarimeter according to the present invention further comprises means for indicating the amount of light received by the light receiving means by changing the light and darkness in the circle figure in gray scale according to the amount of light received by the light receiving means. And

  The polarimeter according to the present invention is characterized by further comprising means for numerically indicating the rotation angle of the analyzer.

  In the present invention, the polarimeter includes an angle display unit that displays a figure that rotates in accordance with the rotation of the analyzer, and the detector that sequentially changes during rotation measurement by the rotation of the figure of the angle display unit. Displays the rotation angle of the photon.

  In the present invention, the angle display unit displays a circle figure and an angle scale along the circumference of the circle, and a figure such as an arrow that rotates around the center of the circle indicates the angle scale. Indicates the rotation angle.

  Further, in the present invention, the polarimeter is an amount of received light that sequentially changes during the measurement of the optical rotation by a method such as changing the light and darkness in a circle figure according to the amount of light received through the analyzer. Is displayed.

  In the present invention, the polarimeter displays the rotation angle of the analyzer numerically.

  In the present invention, the rotation angle of the analyzer is indicated by a figure such as an arrow indicating the angle while rotating during the measurement of the optical rotation with the polarimeter. Thus, the rotation angle of the analyzer being measured can be intuitively known. In addition, the user can intuitively estimate the value of the optical rotation before the measurement of the optical rotation is completed by observing the rotation angle of the analyzer that changes sequentially.

  In the present invention, since the amount of light received through the analyzer is indicated by the brightness of the figure during the measurement of the optical rotation with the polarimeter, the user can intuitively know the progress of the optical rotation measurement. And can estimate the waiting time until the end of the measurement intuitively.

  In the present invention, since the polarimeter indicates the rotation angle of the analyzer numerically, the user can determine the rotation angle of the analyzer separately from knowing the rotation angle of the analyzer intuitively. The present invention has excellent effects such as being able to know accurately and knowing the measured optical rotation accurately.

It is a block diagram which shows the internal structure of the polarimeter of this invention. It is a conceptual diagram which shows the change of the polarization plane of a linearly polarized light. It is a conceptual diagram which shows the relationship between the transmission axis of the rotated analyzer, and the polarization plane of a linearly polarized light. It is a schematic diagram which shows the external appearance of the polarimeter of this invention. It is a schematic diagram which shows the example of a display screen of a display part. It is a schematic diagram which shows the relationship between the rotation angle of an analyzer, and the brightness of a circular figure. It is a schematic diagram which shows the example of the change of the display content of the angle display part according to the state of a polarimeter. It is a schematic diagram which shows the other example of a design of an angle display part. It is a schematic diagram which shows the example of a display of the display part 4 which shows the rotation angle of an analyzer and the light-receiving amount of a light receiving element by another method.

Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
FIG. 1 is a block diagram showing the internal configuration of the polarimeter of the present invention. The arrow in the figure is the optical path, and the polarimeter includes a light source 31, an interference filter 32, a lens 33, a polarizer 11, a sample cell 12, a Faraday coil 13, a hollow motor 14, an analyzer 15, a lens 34, a light receiving element (light receiving element). (Means) 16 are arranged along the optical path. The light source 31 is an LED (light emitting diode) that emits light of a specific wavelength, and is connected to the lighting circuit 30. The light source 31 is supplied with lighting power from the lighting circuit 30 and emits light. The light source 31 may be a light source other than an LED. The interference filter 32 is an optical filter that removes light having a wavelength other than a specific wavelength used for measuring the optical rotation.

  The polarizer 11 is a polarizing plate that transmits only a linearly polarized light component parallel to a single transmission axis, and converts light incident from the light source 31 through the interference filter 32 and the lens 33 into linearly polarized light. To do. Thereby, linearly polarized light is generated. Since the polarizer 11 is fixed in the polarimeter and the direction of the transmission axis inherent to the polarizer 11 is also fixed, the polarization plane of the polarized light generated by the polarizer 11 is constant. The sample cell 12 is a transparent cell filled with the sample solution, and is arranged at a position where the optical path passes through the sample solution. The Faraday coil 13 is disposed at a position where the optical path passes through the Faraday coil 13 and is connected to an oscillator 22 that transmits an alternating current. The oscillator 22 supplies an alternating current having a predetermined frequency to the Faraday coil 13, and the Faraday coil 13 generates an oscillating magnetic field therein by being supplied with the alternating current. The plane of polarization of the linearly polarized light passing through the Faraday coil 13 is oscillated and oscillated by an oscillating magnetic field with an amplitude and frequency corresponding to an alternating current. The order in which the Faraday coil 13 and the sample cell 12 are arranged may be reversed.

  The hollow motor 14 is an electric motor formed in a hollow cylindrical shape, and is disposed at a position where the optical path passes through the hollow portion. An analyzer 15 is fixed to the rotor of the hollow motor 14 at a position where the opening of the hollow motor 14 is closed. The analyzer 15 is a polarizing plate having a single transmission axis. The linearly polarized light that has passed through the sample cell 12 and the Faraday coil 13 passes through the hollow portion of the hollow motor 14 and enters the analyzer 15. Of the linearly polarized light incident on the analyzer 15, only the linearly polarized light component parallel to the transmission axis passes through the analyzer 15. The hollow motor 14 is connected to a motor driver 23 and is configured to rotate the rotor when supplied with a drive current from the motor driver 23. As the rotor of the hollow motor 14 rotates, the analyzer 15 fixed to the rotor rotates. As the analyzer 15 rotates, the direction of the transmission axis inherent to the analyzer 15 changes, and the intensity of linearly polarized light that passes through the analyzer 15 changes.

  The linearly polarized light transmitted through the analyzer 15 is incident on the light receiving element 16 through the lens 34. The light receiving element 16 is configured by a photodiode or the like, and receives linearly polarized light, and outputs a received light signal indicating the amount of received light as a voltage to the amplifying unit 24. The intensity of the light reception signal output by the light receiving element 16 corresponds to the amount of light received by the light receiving element 16.

  The polarimeter of the present invention further includes a signal processing unit 21 that performs signal processing for controlling the operation of the polarimeter based on the received light signal output from the light receiving element 16. The signal processing unit 21 is connected to an oscillator 22, a motor driver 23, and an amplification unit 24. The amplification unit 24 amplifies the light reception signal output from the light receiving element 16 and inputs the amplified light reception signal to the signal processing unit 21. 21 outputs a control signal for operating the oscillator 22 and the motor driver 23. The hollow motor 14 and the motor driver 23 correspond to the rotating means in the present invention. The signal processing unit 21 is an input / output interface for inputting / outputting various signals, an arithmetic unit such as a microprocessor or an integrated circuit for executing various arithmetic processes, a memory for storing temporary information necessary for signal processing, The storage unit stores a processing program and data necessary for signal processing. The signal processing unit 21 is connected to a display unit 4 for displaying information such as the optical rotation measurement result and an operation unit 25 for receiving various instructions such as measurement start of optical rotation by the user's operation. Yes. The signal processing unit 21 performs signal processing for controlling the operation of each unit in accordance with the stored processing program.

  In a stage before the measurement of the optical rotation, the rotation position of the analyzer 15 is set to an initial rotation position where the transmission axes of the polarizer 11 and the analyzer 15 are orthogonal to each other. A state in which the transmission axes of the polarizer 11 and the analyzer 15 are orthogonal to each other is called a crossed Nicol state. In the crossed Nicol state, when there is no sample solution in the sample cell 12, the polarization plane of linearly polarized light incident on the analyzer 15 is orthogonal to the transmission axis of the analyzer 15, so that all light is shielded by the analyzer 15. The light receiving element 16 cannot receive light.

  When a sample solution having optical activity is injected into the sample cell 12, the plane of polarization of linearly polarized light is rotated by the sample solution, and the linearly polarized light component parallel to the transmission axis of the analyzer 15 is transmitted through the analyzer 15, and the light receiving element. 16 detects light. The signal processing unit 21 performs a process of outputting a control signal for causing the oscillator 22 to generate an alternating current, and the oscillator 22 supplies an alternating current having a predetermined frequency f to the Faraday coil 13. The Faraday coil 13 generates an oscillating magnetic field that oscillates at a frequency f by being supplied with an alternating current having a predetermined frequency f. The polarization plane of the linearly polarized light passing through the Faraday coil 13 is oscillated and oscillated at a frequency f by the oscillating magnetic field. At this time, the polarization plane of the linearly polarized light oscillates at a frequency f with a vibration angle width corresponding to the amplitude of the oscillating magnetic field generated by the Faraday coil 13.

  FIG. 2 is a conceptual diagram showing changes in the polarization plane of linearly polarized light. The arrows shown in the figure indicate the polarization direction parallel to the plane of polarization of linearly polarized light and perpendicular to the traveling direction. The direction of angle 0 is the direction of the transmission axis of the polarizer 11, and the direction of angle 90 ° is the direction of the transmission axis of the analyzer 15 arranged at the initial rotation position. FIG. 2A shows the polarization plane of linearly polarized light that has passed through the polarizer 11, and the polarization direction is orthogonal to the transmission axis of the analyzer 15. FIG. 2B shows a polarization plane of linearly polarized light that has passed through the sample solution in the sample cell 12. The plane of polarization of linearly polarized light is rotated by the optical rotation of the sample solution, and the angle formed by the plane of polarization and the direction of angle 0 is the optical rotation α of the sample solution. FIG. 2C shows the plane of polarization of linearly polarized light that has further passed through the Faraday coil 13. The polarization plane performs oscillating vibration in which the angle formed with the direction of the angle 0 periodically varies with the vibration angular width δ around the angle α. FIG. 2C shows an example where α> δ.

  The signal processing unit 21 performs processing for outputting a pulse signal for rotating the hollow motor 14 to the motor driver 23. The motor driver 23 supplies a drive current corresponding to the pulse signal from the signal processing unit 21 to the hollow motor 14, and the hollow motor 14 rotates the analyzer 15. The rotation direction of the hollow motor 14 is determined by the type of pulse signal output from the signal processing unit 21, and the rotation angle is determined by the number of pulse signals. The hollow motor 14 rotates the analyzer 15 in the direction corresponding to the signal from the signal processing unit 21 by the rotation angle corresponding to the pulse signal, and then stops. Further, the signal processing unit 21 performs a process of measuring the rotation angle of the hollow motor 14 that has rotated the analyzer 15 from the initial rotation position in the crossed Nicol state based on the number of output pulse signals. By multiplying the number of pulse signals for rotating the rotor of the hollow motor 14 by one step until the current rotation position is multiplied by the angle at which the rotor rotates in one step, the hollow motor 14 rotation angles can be measured.

  FIG. 3 is a conceptual diagram showing the relationship between the transmission axis of the rotated analyzer 15 and the polarization plane of linearly polarized light. Let β be the rotation angle of the analyzer 15 rotated from the initial rotation position by the hollow motor 14. In the drawing, the transmission axis of the rotated analyzer 15 is shown, and the angle formed by the direction of the angle 90 ° and the transmission axis of the rotated analyzer 15 is the rotation angle β. In the drawing, the direction perpendicular to the transmission axis of the analyzer 15 is indicated by a broken line. When the plane of polarization of the linearly polarized light oscillates, the angle between the plane of polarization of the linearly polarized light incident on the analyzer 15 and the transmission axis of the analyzer 15 oscillates at the frequency f. The vibration angle width δ at this time is a vibration angle width corresponding to the amplitude of the oscillating magnetic field generated by the Faraday coil 13. As for the linearly polarized light incident on the rotated analyzer 15, only the linearly polarized light component parallel to the transmission axis of the analyzer 15 is transmitted through the analyzer 15. The light transmitted through the analyzer 15 is received by the light receiving element 16.

  The light receiving element 16 that has received the light outputs a light receiving signal indicating the amount of light received in voltage, and the amplifying unit 24 amplifies the light receiving signal and inputs it to the signal processing unit 21. As shown in FIG. 3, the angle formed by the plane of polarization of the linearly polarized light incident on the analyzer 15 and the transmission axis of the analyzer 15 is oscillating at the frequency f, so that the analyzer 15 included in the linearly polarized light The magnitude of the linearly polarized light component parallel to the transmission axis also vibrates at the frequency f. Since the magnitude of the linearly polarized light component transmitted through the analyzer 15 vibrates at the frequency f, the amount of light received by the light receiving element 16 that has received the light transmitted through the analyzer 15 vibrates at the frequency f. Accordingly, the light reception signal indicating the amount of light received by the light receiving element 16 as a voltage is an AC signal in which the voltage vibrates at the frequency f.

  The closer the angle at which the plane of polarization of the linearly polarized light intersects the transmission axis of the analyzer 15 is closer to a right angle, the smaller the linearly polarized light component that is transmitted through the analyzer 15 is, and the amount of light received by the light receiving element 16 is reduced. Becomes smaller. When β = α, the transmission axis of the analyzer 15 is perpendicular to the center of vibration of the polarization plane, and the range of the angle at which the polarization plane that oscillates and intersects the transmission axis is closest to the right angle. Is minimal. The signal processing unit 21 to which the received light signal is input extracts an alternating current component that vibrates at the same frequency f as the alternating current supplied to the Faraday coil 13 from the received light signal, so that the intensity of the extracted alternating current component becomes smaller. In addition, the rotation of the hollow motor 14 is feedback-controlled. The signal processing unit 21 determines the rotation angle β of the analyzer 15 that minimizes the AC component that vibrates at the frequency f of the received light signal by feedback control, and measures the determined rotation angle β. In the state where the AC component that vibrates at the frequency f of the received light signal is minimized, β = α, and therefore the measured value of the rotation angle β is the optical rotation α of the sample solution. With the above processing, the polarimeter measures the optical rotation α of the sample solution.

  FIG. 4 is a schematic diagram showing the appearance of the polarimeter of the present invention. The polarimeter includes a housing 5, and the internal configuration shown in FIG. 1 is provided in the housing 5. The housing 5 has an opening, and a lid 51 that can be opened and closed is provided in the opening. By opening the lid 51, the sample solution can be injected into the sample cell 12 provided in the housing 5. A display unit 4 is provided on the upper surface of the housing 5. The display unit 4 is configured by a touch panel using a liquid crystal panel, an EL (electroluminescence) panel, or the like integrally with the operation unit 25. Note that the display unit 4 and the operation unit 2 may be configured separately by configuring the display unit 4 with a display and configuring the operation unit 25 with a keyboard or the like.

  FIG. 5 is a schematic diagram illustrating a display screen example of the display unit 4. The display unit 4 includes an angle display unit 41 that indicates the rotation angle of the hollow motor 14 measured by the signal processing unit 21, that is, the rotation angle of the analyzer 15, and the rotation angle of the analyzer 15. And a numerical value display section 42 shown in FIG. The display unit 4 also includes a blank button 43 that receives an instruction to set the initial rotation position of the analyzer 15 and a start button 44 that receives an instruction to start measuring the optical rotation.

  The angle display unit 41 includes a circular graphic 413, an angle scale 412 indicating a rotational angle along the circumference of the circular graphic 413, and an arrow graphic 411 displayed to rotate around the circular graphic 413. It is configured. Each time the signal processing unit 21 measures the rotation angle of the hollow motor 14, the display content of the angle display unit 41 displayed by the display unit 4 so that the arrow shape 411 indicates the measured rotation angle on the angle scale 412. Process to update. For this reason, in accordance with the rotation of the analyzer 15 according to the rotation of the hollow motor 14, the arrow graphic 411 rotates about the center point of the circular graphic 413 as the rotation center, and the rotation angle β of the analyzer 15 is set. Show. Thus, the angle display unit 41 functions as an analog tachometer that indicates the rotation angle of the analyzer 15 that changes sequentially by an arrow.

  The signal processing unit 21 displays the content of the numerical display unit 42 displayed by the display unit 4 so that the numerical display unit 42 displays the value of the measured rotational angle each time the rotational angle of the hollow motor 14 is measured. Process to update. Therefore, the numerical value display unit 42 displays the value of the rotation angle β of the analyzer 15 according to the rotation of the analyzer 15 according to the rotation of the hollow motor 14. As described above, the numerical value display unit 42 functions as a digital tachometer that displays the value of the rotation angle of the analyzer 15 that changes sequentially. The polarimeter includes a temperature sensor (not shown) that measures the internal temperature, and the signal processing unit 21 performs processing for displaying the temperature measured by the temperature sensor on the numerical value display unit 42.

  Further, the signal processing unit 21 performs a process of changing the light and darkness in the circular pattern 412 on the display unit 4 according to the intensity of the light reception signal from the light receiving unit 16. Specifically, in the signal processing unit 21, as the intensity of the alternating current component that vibrates at the frequency f of the received light signal is larger, the inside of the circular pattern 413 becomes brighter and the intensity of the alternating current component that vibrates at the frequency f of the received light signal is smaller. Control is performed to change the brightness in the circular figure 413 so that the circular figure 413 becomes darker. The display unit 4 expresses the light and dark in the circular figure 413 in gray scale, and changes the light and dark according to the control of the signal processing unit 21.

  FIG. 6 is a schematic diagram showing the relationship between the rotation angle β of the analyzer 15 and the brightness of the circular pattern 413. When the value (α−β) obtained by subtracting the rotation angle β of the analyzer 15 from the optical rotation α of the sample solution changes, the angle at which the plane of polarization of the linearly polarized light and the transmission axis of the analyzer 15 intersect changes. Since the amount of light received by the light receiving element 16 changes and the intensity of the light receiving signal changes, the brightness in the circular pattern 413 changes. When (α−β) is 0 °, the intensity of the received light signal is minimized, so that the circular figure 413 is darkest. A crossed Nicol state in which there is no sample solution in the sample cell 12 is when (α−β) is 0 °. As the amount of light received by the light receiving element 16 increases as (α−β) increases from 0 °, the inside of the circular pattern 413 becomes brighter. When (α−β) is 90 °, the plane of polarization of linearly polarized light and the transmission axis of the analyzer 15 are substantially parallel, the intensity of the received light signal is maximized, and the inside of the circular pattern 413 is brightest. The same applies when (α−β) changes to the negative side.

  During the process in which the polarimeter measures the optical rotation of the sample solution, the analyzer 15 is rotating, so that the amount of light received by the light receiving element 16 and the intensity of the received light signal change sequentially, and the light and darkness in the circular pattern 413 changes. Also changes sequentially. Since the signal processing unit 21 performs feedback control so that the intensity of the received light signal becomes smaller, the brightness changes so that the circular figure 413 gradually becomes dark during the measurement of the optical rotation. At the time when β = α, the measurement of the optical rotation is completed, and at this time, the inside of the circular figure 413 becomes the darkest. Therefore, the user can know the progress status of the optical rotation measurement by monitoring the brightness of the circular figure 413.

  FIG. 7 is a schematic diagram illustrating an example of a change in display content of the angle display unit 41 according to the state of the polarimeter. When measuring the optical rotation, the user first presses the blank button 43 of the display unit 4 in a state where the sample solution is not injected into the sample cell 12. In response to pressing of the blank button 43, the signal processing unit 21 performs feedback control of the hollow motor 14 so that the intensity of the received light signal is minimized, thereby determining the initial rotation position of the analyzer 15 in the crossed Nicols state. To do. The signal processing unit 21 initializes the rotation angle of the analyzer 15 with the rotation position of the analyzer 15 set to the initial rotation position to a rotation angle of 0 °. As a result, as shown in FIG. 7A, the state of the angle display unit 41 is that the circular figure 413 is the darkest and the arrow figure 411 indicates 0 °. At the same time, the numerical value display unit 42 displays 0 ° as a numerical value.

  Next, the user opens the lid 51, injects the sample solution into the sample cell 12, closes the lid 51, and then presses the start button 44 of the display unit 4. FIG. 7B shows the angle display unit 41 in a state where the sample solution is injected into the sample cell 12. Since the measurement has not yet been started, the arrow graphic 411 remains at 0 °, but the polarization plane of linearly polarized light is rotated by the sample solution and the amount of light received by the light receiving element 16 is increased. It is displayed brightly. In response to pressing of the start button 44, the signal processing unit 21 starts feedback control of the hollow motor 14. FIG.7 (c) shows the angle display part 41 in the middle of the measurement of optical rotation. In accordance with the rotation of the analyzer 15, the arrow graphic 411 rotates around the center of the circular graphic 413, and indicates the current rotation angle of the analyzer 15. At the same time, the rotation angle is displayed as a numerical value on the numerical value display unit 42. Since the analyzer 15 is rotated so that the intensity of the received light signal becomes smaller, the circular pattern 413 becomes darker than at the start of measurement.

  At the stage where the light reception signal is minimized, the signal processing unit 21 ends the feedback control and stops the rotation of the analyzer 15. FIG. 7D shows the angle display unit 41 in a state where the measurement of the optical rotation is completed. The arrow graphic 411 stops the rotation in response to the stop of the rotation of the analyzer 15, and indicates the final rotation angle of the analyzer 15, that is, the optical rotation of the sample solution. In the state where the measurement of the optical rotation is completed, since the light reception signal is minimum, the circular figure 413 becomes darkest again. The signal processing unit 21 performs a process of displaying the final rotation angle value of the analyzer 15 on the numerical value display unit 42 as the measured optical rotation value.

  As described above in detail, in the polarimeter of the present invention, the angle display unit 41 displayed on the display unit 4 functions as an analog tachometer, and the rotation angle of the analyzer 15 that changes sequentially during the measurement of the optical rotation is obtained. This is indicated by an arrow graphic 411. The user can intuitively know the current rotation angle of the analyzer 15 from the change of the arrow graphic 411 on the angle display unit 41. In addition, since the rotation angle finally indicated by the arrow graphic 411 is the optical rotation of the sample solution, the user can observe the change in the rotation angle before the measurement of the optical rotation is completed. It is possible to intuitively estimate the value of. In the polarimeter of the present invention, the numerical value display unit 42 functions as a digital tachometer, and indicates the rotation angle of the analyzer 15 by a numerical value. The user can accurately know the rotation angle of the analyzer 15 during the measurement of the optical rotation and the optical rotation of the sample solution by checking the display of the numerical value display unit 42.

  In the polarimeter of the present invention, the progress of the optical rotation measurement is shown by changing the brightness of the circular figure 413 included in the angle display unit 41 according to the amount of light received by the light receiving element 16. For example, it becomes apparent that the brighter the circular figure 413, the shorter the elapsed time from the start of measurement, and the darker the circular figure 413, the shorter the time required for the end of measurement. Further, the user can intuitively estimate the waiting time until the end of the measurement by judging the brightness of the circular figure 413. As described above, the user who uses the polarimeter of the present invention visually recognizes the rotation angle indicated by the arrow graphic 411 and the brightness of the circular graphic 413 on the angle display unit 41, and thereby the state of the polarimeter during the optical rotation measurement. Can know.

  In addition, the design of the angle display part 41 in this invention is not restricted to the example shown in FIG. 5, You may comprise the angle display part 41 by another design. FIG. 8 is a schematic diagram illustrating another design example of the angle display unit 41. In the example shown in FIG. 5, the arrow graphic 411 is arranged inside the circular graphic 413, but in the example shown in FIG. 8, the arrow graphic 411 is arranged on the outer periphery of the circular graphic 413. Further, the polarimeter of the present invention is a mode in which the rotation angle of the analyzer 15 is indicated by a method other than the rotating arrow graphic 411 and the amount of light received by the light receiving element 16 is indicated by a method other than the brightness in the circular graphic 413. Also good. FIG. 9 is a schematic diagram illustrating a display example of the display unit 4 indicating the rotation angle of the analyzer 15 and the amount of light received by the light receiving element 16 by other methods. FIG. 9A shows a display example showing the rotation angle of the analyzer 15, and in this example, the rotation angle of the analyzer 15 is indicated by a needle figure rotating around one end. FIG. 9B shows a display example indicating the amount of light received by the light receiving element 16. In this example, the amount of light received by the light receiving element 16 is indicated by the expansion and contraction of a bar graph-like indicator. Further, the polarimeter does not display the angle display unit 41 on the display unit 4 that is a touch panel, but may include a mechanical meter that indicates the rotation angle of the analyzer 15 and the amount of light received by the light receiving element 16. Good. The effects of the present invention are also realized in these forms.

DESCRIPTION OF SYMBOLS 11 Polarizer 12 Sample cell 13 Faraday coil 14 Hollow motor 15 Analyzer 16 Light receiving element (light receiving means)
DESCRIPTION OF SYMBOLS 21 Signal processing part 22 Oscillator 23 Motor driver 31 Light source 4 Display part 41 Angle display part 411 Arrow figure 412 Angle scale 413 Circular figure 42 Numerical display part

Claims (5)

An analyzer that receives linearly polarized light, a rotating unit that rotates the analyzer, and a light receiving unit that receives light transmitted through the analyzer, and the linearly polarized light after passing through a sample is the analyzer. In a polarimeter that measures the optical rotation of the sample based on the angle by which the analyzer is rotated by the rotating means so that the amount of light received by the light receiving means is minimized.
An optical rotation meter comprising an angle display unit that indicates a rotation angle of the analyzer using a figure that rotates in accordance with the rotation of the analyzer by the rotation means. The angle display unit includes a circle figure, an angle scale along the circle, and a figure that rotates according to the rotation of the analyzer with the center point of the circle as a rotation center while pointing to the angle scale. The polarimeter according to claim 1, wherein the polarimeter is configured to display. The polarimeter according to claim 1 or 2, further comprising means for indicating an amount of light received by the light receiving means. The apparatus according to claim 2, further comprising means for indicating the amount of light received by the light receiving means by changing light and darkness in the circle figure in gray scale according to the amount of light received by the light receiving means. Polarimeter. The polarimeter according to any one of claims 1 to 4, further comprising means for numerically indicating a rotation angle of the analyzer.

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