JP2019219681A - Polarization microscope - Google Patents

Abstract

To provide a polarization microscope having a simplified structure.SOLUTION: A polarizer 7 is disposed on the optical path from a visible light source 3 to a sample, which transmits a beam of light from visible light source 3 to thereby generate linearly polarized light whose polarization plane is along the first direction. An analyzer 8 is disposed on the optical path of a beam of light after being radiated to the sample, and transmits the linearly polarized light whose polarization plane is along the second direction. A rotation mechanism 9 rotates the analyzer 8 to thereby transit among orthogonal state where first direction and second direction are orthogonal, parallel state where first direction and second direction extend in parallel, and evacuation state without analyzer 8 on optical path.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a polarizing microscope including a polarizer and an analyzer.

  Some optical microscopes for observing a sample surface function as a polarizing microscope by providing a polarizer and an analyzer (for example, see Patent Document 1 below). In a polarizing microscope, visible light emitted from a visible light source is incident on a polarizer and is transmitted through the polarizer to generate linearly polarized light. Then, the sample is irradiated with linearly polarized light that has passed through the polarizer, and light (transmitted light or reflected light) from the sample passes through the analyzer and enters the camera.

  The polarization microscope includes a rotation mechanism for rotating the analyzer, and a slide mechanism for sliding the analyzer and the rotation mechanism. When the analyzer is rotated by the rotation mechanism, the angle relative to the polarizer changes. Thus, among the light from the sample, the light that passes through the analyzer and enters the camera changes, so that the polarization image can be observed by photographing the change with the camera.

  On the other hand, when the analyzer and the rotation mechanism are slid by the slide mechanism and the analyzer is retracted from the optical path, light from the sample directly enters the camera without passing through the analyzer. In this case, an optical image can be observed by photographing visible light from the sample with a camera.

JP 2012-211771 A

  However, in the conventional polarization microscope as described above, it is necessary to provide both a rotation mechanism and a slide mechanism. Therefore, in the case of electric operation, a power source such as a motor must be provided for each of the rotation mechanism and the slide mechanism. In the case of manual operation, a plurality of gripping portions for the operator to grip and operate must be provided. Must. Therefore, there was a problem that the structure became complicated.

  The present invention has been made in view of the above circumstances, and has as its object to provide a polarizing microscope having a simplified structure.

(1) A polarizing microscope according to the present invention includes a light source, a polarizer, an analyzer, and a moving mechanism. The light source emits light toward the sample. The polarizer is disposed on an optical path from the light source to a sample, and transmits light from the light source to generate linearly polarized light having a polarization plane along a first direction. The analyzer is arranged on the optical path of the light after irradiating the sample, and transmits linearly polarized light whose polarization plane is along the second direction. The moving mechanism relatively moves the polarizer and the analyzer to form an orthogonal state in which the first direction and the second direction are orthogonal to each other, and the first direction and the second direction. Can be changed between a parallel state in which the light-emitting elements extend parallel to each other and a retracted state in which the polarizer or the analyzer does not exist on the optical path.

  According to such a configuration, transition can be made between the orthogonal state, the parallel state, and the retracted state by using one moving mechanism that relatively moves the polarizer and the analyzer. Therefore, there is no need to separately provide a mechanism for making a transition between the orthogonal state and the parallel state and a mechanism for making a transition to the retracted state, so that a polarization microscope with a simplified structure can be provided.

(2) The moving mechanism may rotate the polarizer or the analyzer around a rotation axis.

  According to such a configuration, it is possible to make a transition between the orthogonal state, the parallel state, and the retracted state with a simple mechanism that only adjusts the rotation angle of the polarizer or the analyzer.

(3) The rotation axis may pass through the center of gravity of the polarizer or the analyzer.

  According to such a configuration, since the rotation axis of the polarizer or the analyzer that is rotated and moved is not eccentric, it is possible to prevent the polarizer or the analyzer from rotating due to gravity. Therefore, there is no need to provide a stopper or a brake for preventing the polarizer or the analyzer from rotating due to gravity, so that the structure can be further simplified.

(4) The polarizer or the analyzer transitions between the orthogonal state, the parallel state, and the retracted state by rotating at a rotation angle of 90 ° or more and less than 360 ° around the rotation axis. You may.

  According to such a configuration, the transition between the orthogonal state, the parallel state, and the retracted state is made by simply adjusting the rotation angle of the polarizer or the analyzer within a range of 90 ° or more and less than 360 ° about the rotation axis. be able to. Since the transition between the orthogonal state and the parallel state can be made at a rotation angle of 90 °, it is possible to make a transition to the retracted state by rotating the polarizer or the analyzer to a larger rotation angle.

(5) The polarizer or the analyzer may have a shape having a notch in a part of a disk, and may be in the retracted state when the notch is located on an optical path.

  According to such a configuration, a simple configuration in which a polarizer or an analyzer is formed in a shape having a notch in a part of a disk can be used to make a transition to a retracted state using the notch. it can.

(6) The light source may include a visible light source that emits visible light toward the sample, and an infrared light source that emits infrared light toward the sample. In this case, the polarizer and the analyzer may be arranged on an optical path of visible light emitted from the visible light source.

  According to such a configuration, at the time of observation using visible light with an infrared microscope, by simply moving the polarizer and the analyzer relatively using the moving mechanism, it is possible to switch between the orthogonal state, the parallel state, and the retracted state. You can make a transition.

(7) The polarizer and the analyzer may be arranged on an optical path of infrared light emitted from the infrared light source.

  According to such a configuration, at the time of observation using infrared light with an infrared microscope, by simply moving the polarizer and the analyzer relatively using the moving mechanism, the apparatus moves between the orthogonal state, the parallel state, and the retracted state. Can be changed.

  According to the present invention, there is no need to separately provide a mechanism for making a transition between the orthogonal state and the parallel state and a mechanism for making a transition to the retracted state, so that a polarization microscope having a simplified structure is provided. be able to.

FIG. 1 is a schematic diagram illustrating a configuration example of an infrared microscope functioning as a polarizing microscope according to an embodiment of the present invention. FIG. 5 is a schematic diagram for explaining a change in the direction of linearly polarized light when the analyzer is rotated. FIG. 5 is a schematic diagram for explaining a change in the direction of linearly polarized light when the analyzer is rotated. FIG. 5 is a schematic diagram for explaining a change in the direction of linearly polarized light when the analyzer is rotated. FIG. 3 is a diagram illustrating an example of a specific configuration of an analyzer. FIG. 6 is a diagram showing another example of the specific configuration of the analyzer.

1. Configuration of Infrared Microscope FIG. 1 is a schematic diagram showing a configuration example of an infrared microscope 100 functioning as a polarizing microscope according to one embodiment of the present invention. The infrared microscope 100 can irradiate a sample with infrared light and visible light. The infrared microscope 100 includes a sample stage 1, an infrared light source 2, a visible light source 3, a detector 4, a camera 5, a beam splitter 6, a Cassegrain mirror 200, and the like.

  On the sample stage 1, a sample to be analyzed is placed. The sample stage 1 is configured to be movable in, for example, a horizontal direction (XY directions) and a vertical direction (Z direction). In the present embodiment, a pair of Cassegrain mirrors 200 is provided above and below the sample stage 1.

  The Cassegrain mirror 200 (upper Cassegrain mirror 200A) installed above the sample stage 1 and the Cassegrain mirror 200 (lower Cassegrain mirror 200B) installed below the sample stage 1 have the same configuration. However, the installation direction is different. The upper Cassegrain mirror 200A and the lower Cassegrain mirror 200B are arranged coaxially so that their respective axes extend in the vertical direction.

  The infrared light source 2 is configured by an FTIR (Fourier transform infrared spectrophotometer), and can generate an interference wave of infrared light using a fixed mirror and a movable mirror (not shown). The infrared light emitted from the infrared light source 2 is irradiated onto the sample stage 1 via the Cassegrain mirror 200. When performing the reflection measurement, the infrared light emitted from the infrared light source 2 is sequentially reflected by the reflection mirrors 21, 22, 23, 24, 25, 26, and 27 and then introduced into the upper Cassegrain mirror 200 </ b> A from above. Is done.

  The reflection mirror 25 is formed of, for example, a parabolic mirror having a reflection surface formed of a paraboloid, and infrared light incident on the reflection mirror 25 as parallel light is collected by being reflected by the reflection mirror 25. You. The reflection mirror 25 can change the angle of the reflection surface by rotating as shown by a broken line in FIG. When the transmission measurement is performed, the angle of the reflection mirror 25 is changed so that the infrared light emitted from the infrared light source 2 is reflected by the reflection mirrors 21, 22, 23, and 24 sequentially, and then reflected by the reflection mirror 25. , 28, and 29, and is introduced into the lower Cassegrain mirror 200B from below.

  The visible light source 3 emits visible light (for example, white) for observing the sample, and irradiates the sample stage 1 via the Cassegrain mirror 200. The visible light emitted from the visible light source 3 is guided to the Cassegrain mirror 200 through an optical path that is mostly common to the optical path of the infrared light. The reflection mirror 24 is composed of, for example, a beam splitter, and visible light emitted from the visible light source 3 is transmitted through the reflection mirror 24 and guided on an optical path common to infrared light. The visible light transmitted through the reflection mirror 24 can be introduced from above into the upper Cassegrain mirror 200A through the reflection mirrors 25, 26, and 27 similarly to the infrared light emitted from the infrared light source 2, and can be reflected. It can also be introduced into the lower Cassegrain mirror 200B from below via the mirrors 25, 28, 29.

  The Cassegrain mirror 200 includes, for example, a primary mirror 201 and a secondary mirror 202. The primary mirror 201 has a reflecting surface formed of a spherical concave surface. On the other hand, the secondary mirror 202 has a reflecting surface formed of a spherical convex surface. The reflecting surface of the secondary mirror 202 is smaller in diameter than the reflecting surface of the primary mirror 201. The main mirror 201 and the sub-mirror 202 are mounted such that the centers of the respective reflecting surfaces are located on the same axis. More specifically, the reflection surface of sub-mirror 202 faces the reflection surface of main mirror 201 with a space.

  The infrared light and the visible light are reflected by the reflecting surface of the secondary mirror 202 and then reflected by the reflecting surface of the primary mirror 201. At this time, a part of the light reflected by the reflection surface of the primary mirror 201 is blocked by the secondary mirror 202, but the other light is emitted from the side of the secondary mirror 202 and collected at the measurement position P. Is lighted.

  When the reflection measurement is performed, the infrared light and the visible light introduced into the upper Cassegrain mirror 200A are sequentially reflected by the sub-mirror 202 and the main mirror 201, and then are moved from above to the measurement position P on the sample stage 1. It is collected. The reflected light from the sample placed at the measurement position P enters the upper Cassegrain mirror 200A again, is sequentially reflected by the primary mirror 201 and the secondary mirror 202, and then exits upward from the upper Cassegrain mirror 200A.

  On the other hand, when the transmission measurement is performed, the infrared light and the visible light introduced into the lower Cassegrain mirror 200B are sequentially reflected by the sub-mirror 202 and the main mirror 201, and then reflected at the measurement position P on the sample stage 1. Light is collected from below. Then, transmitted light from the sample placed at the measurement position P enters the upper Cassegrain mirror 200A. The light that has entered the upper Cassegrain mirror 200A is sequentially reflected by the primary mirror 201 and the secondary mirror 202, and then exits upward from the upper Cassegrain mirror 200A.

  Light (reflected light or transmitted light) from the sample emitted upward from the upper Cassegrain mirror 200 </ b> A is guided to the beam splitter 6. The beam splitter 6 transmits one of visible light and infrared light and reflects the other. In the present embodiment, a configuration in which the beam splitter 6 transmits visible light and reflects infrared light will be described. However, the beam splitter 6 is configured to transmit infrared light and reflect visible light. You may.

  The infrared light irradiated to the sample and reflected or transmitted by the sample is reflected by the beam splitter 6, then reflected by the reflection mirror 30, and enters the detector 4. As a result, a detection signal is output from the detector 4, and reflection measurement or transmission measurement of the sample can be performed based on the detection signal. On the other hand, the visible light radiated to the sample and reflected or transmitted by the sample passes through the beam splitter 6, is reflected by the reflection mirror 31 and enters the camera 5. Thus, the image illuminated by the visible light can be captured by the camera 5 and the image can be confirmed.

  In the present embodiment, the polarizer 7 and the analyzer 8 are arranged on the optical path of the visible light emitted from the visible light source 3. The polarizer 7 is arranged on the optical path from the visible light source 3 to the sample, and the analyzer 8 is arranged on the optical path of visible light after irradiating the sample. The polarizer 7 and the analyzer 8 are both arranged on the optical path of only visible light, and are arranged so as not to be located on the optical path of infrared light.

  The polarizer 7 transmits the visible light from the visible light source 3 to generate linearly polarized light whose polarization plane is along the first direction. That is, of the visible light incident on the polarizer 7, only the light that vibrates along the first direction passes through the polarizer 7 and is irradiated on the sample as linearly polarized light. The polarizer 7 is disposed so as to be orthogonal to the optical axis of the visible light from the visible light source 3. The linearly polarized light applied to the sample is reflected or transmitted by the sample, so that the vibration direction becomes irregular, and then enters the analyzer 8.

  The analyzer 8 transmits linearly polarized light whose polarization plane is along the second direction. That is, of the reflected light or transmitted light from the sample, only light that vibrates in the second direction passes through the analyzer 8 and enters the camera 5 as linearly polarized light. The analyzer 8 is disposed so as to be orthogonal to the optical axis of the reflected light or transmitted light from the sample.

  In the present embodiment, the analyzer 8 is held rotatably around a rotation axis A orthogonal to the analyzer 8. The rotation axis A extends parallel to the optical axis of the reflected light or transmitted light from the sample incident on the analyzer 8. The analyzer 8 is driven to rotate about the rotation axis A by a rotation mechanism (moving mechanism) 9 including a drive source such as a motor.

  By rotating the analyzer 8 about the rotation axis A using the rotation mechanism 9, the relative rotation angle of the analyzer 8 with respect to the polarizer 7 is changed, and the reflected light or transmission from the sample incident on the camera 5 is transmitted. Light can be changed. By changing the image captured by the camera 5 in this manner, the polarization characteristics of the sample can be observed.

2. 2A to 2C are schematic diagrams for explaining a change in the direction of linearly polarized light when the analyzer 8 is rotated. In the present embodiment, the analyzer 8 is formed in a shape having a notch 82 in a part of a disk 81. The rotation axis A of the analyzer 8 is located, for example, at the center of the disk 81, and a notch 82 is formed in a portion within a certain angle range θ centered on the rotation axis A.

  In this example, the angle range θ is 90 °, but is not limited to 90 °. The angle range θ is preferably less than 180 °, more preferably 90 ° or more and less than 180 °. That is, the portion of the analyzer 8 excluding the notch 82 is preferably 180 ° or more and less than 360 ° around the rotation axis A, and more preferably 180 ° or more and less than 270 °.

  In a state where the sample is not placed at the measurement position P, the light L incident on the analyzer 8 becomes linearly polarized light along the first direction D1. The passing position of the light L is located on the trajectory of the analyzer 8 (disk 81) rotating about the rotation axis A, and is also located on the trajectory of the notch 82. Therefore, by rotating the analyzer 8 about the rotation axis A, the second direction D2 which is the vibration direction of the light passing through the analyzer 8 can be relatively changed with respect to the first direction D1. At the same time, the light L may pass through the notch 82.

  The state of FIG. 2A is an orthogonal state in which the first direction D1 and the second direction D2 are orthogonal. This state is called crossed Nicols, and the light L that is linearly polarized light along the first direction D1 cannot pass through the analyzer 8. On the other hand, the state of FIG. 2B is a parallel state in which the first direction D1 and the second direction D2 extend in parallel. In this state, light L that is linearly polarized light along the first direction D1 can pass through the analyzer 8 as it is.

  The state shown in FIG. 2C is a retracted state in which the analyzer 8 is not on the optical path of the light L. This state is called open Nicol, and the notch 82 is located on the optical path of the light L. Therefore, the light L that is linearly polarized light along the first direction D1 passes through the notch 82 without passing through the analyzer 8.

  As described above, in the present embodiment, the analyzer 8 can be shifted between the orthogonal state, the parallel state, and the retracted state by rotating the analyzer 8 about the rotation axis A. In this example, the angle between the first direction D1 and the second direction D2 is continuously changed by rotating the analyzer 8 clockwise by 90 ° from the orthogonal state in FIG. Can be changed to By rotating the analyzer 8 further 180 ° clockwise from the state of FIG. 2B, it is possible to make a transition to the retracted state of FIG. 2C.

  That is, in the present embodiment, the analyzer 8 can be shifted between the orthogonal state, the parallel state, and the retracted state by rotating the analyzer 8 at a rotation angle of 270 ° about the rotation axis L. However, the rotation angle is not limited to 270 °, and may be any rotation angle that allows transition between the orthogonal state, the parallel state, and the retracted state. In this case, the rotation angle is preferably 90 ° or more and less than 360 °, and more preferably 180 ° or more and 270 ° or less.

3. FIG. 3A is a diagram showing an example of a specific configuration of the analyzer 8. In this example, the analyzer 8 is formed by forming the notch 82 in an angle range of 90 ° with respect to the disk 81. The analyzer 8 includes a main body 83 that transmits linearly polarized light along the second direction D2, and a holding section 84 that holds the outer periphery of the main body 83.

  The holding portion 84 has a configuration in which an outer frame 841 formed in a hollow circular shape and a rib 842 formed along the notch 82 are integrally formed. The holding portion 84 is formed of, for example, resin or metal. The holding portion 84 is a member having a greater thickness than the film-shaped main body 83, and weighs more per unit area than the main body 83. For this reason, the center of gravity of the analyzer 8 is shifted from the center of the disk 81, and in this embodiment, the rotation axis A is arranged so as to pass through the center of gravity of the analyzer 8.

  FIG. 3B is a diagram illustrating another example of the specific configuration of the analyzer 8. In this example, the notch 82 is formed in the angle range of 180 ° with respect to the circular plate 81, thereby forming the semi-circular analyzer 8. The analyzer 8 includes a main body 85 that transmits linearly polarized light along the second direction D2, and a holding unit 86 that holds the outer periphery of the main body 85.

  The holding portion 86 is formed in a hollow semicircular shape. The holding portion 86 is formed of, for example, resin or metal. The holding portion 86 is a member having a thickness greater than that of the film-shaped main body 85, and weighs more per unit area than the main body 85. For this reason, the center of gravity of the analyzer 8 is shifted from the center of the disk 81, and in this embodiment, the rotation axis A is arranged so as to pass through the center of gravity of the analyzer 8.

4. Operation and Effect (1) In the present embodiment, as shown in FIGS. 2A to 2C, a single moving mechanism (rotating mechanism 9) for relatively moving the polarizer 7 and the analyzer 8 is used. A transition can be made between the state and the evacuation state. Therefore, there is no need to separately provide a mechanism for making a transition between the orthogonal state and the parallel state and a mechanism for making a transition to the retracted state, so that it is possible to provide the infrared microscope 100 having a simplified structure. it can.

(2) In particular, since the moving mechanism is constituted by the rotating mechanism 9 for rotating and moving the analyzer 8 about the rotation axis A, the moving mechanism is a simple mechanism for adjusting the rotation angle of the analyzer 8 and is orthogonal. A transition can be made between the state, the parallel state, and the retracted state.

(3) In addition, as illustrated in FIG. 3A or FIG. 3B, if the rotation axis A passes through the center of gravity of the analyzer 8, the rotation axis A of the analyzer 8 that is rotated and moved is deviated. Since the analyzer 8 is not centered, the analyzer 8 can be prevented from rotating by gravity. Therefore, since it is not necessary to provide a stopper or a brake for preventing the analyzer 8 from rotating by gravity, the structure can be further simplified. Such an effect is particularly remarkable when the rotation axis A extends in a direction intersecting the vertical direction (for example, a horizontal direction).

(4) Further, in the present embodiment, the orthogonal state, the parallel state, and the retreating state are achieved only by adjusting the rotation angle of the analyzer 8 within a range of 90 ° or more and less than 360 ° (for example, 270 °) around the rotation axis A. Transitions can be made between states. Since the transition between the orthogonal state and the parallel state can be made at a rotation angle of 90 °, it is possible to make a transition to the retracted state by rotating the analyzer 8 to a larger rotation angle.

(5) Further, in the present embodiment, as illustrated in FIG. 3A or FIG. 3B, the analyzer 8 has a simple configuration in which the analyzer 8 is simply formed in a shape having a notch 82 in a part of a disk 81. Using the portion of the notch 82, the state can be changed to the retreat state.

5. Modification (1) In the above embodiment, the configuration in which the analyzer 8 is arranged on the optical path of the visible light emitted from the visible light source 3 has been described. In this case, at the time of observation using visible light in the infrared microscope 100, the polarizer 7 and the analyzer 8 are relatively moved using the moving mechanism (rotating mechanism 9), and the orthogonal state, the parallel state, and the retracted state are obtained. Can be transitioned between

  However, the configuration is not limited to such a configuration, and the analyzer 8 may be arranged on the optical path of infrared light emitted from the infrared light source 2. In this case, at the time of observation using the infrared light in the infrared microscope 100, the transition between the orthogonal state, the parallel state, and the retracted state is performed only by relatively moving the polarizer and the analyzer using the moving mechanism. Can be.

(2) In the above embodiment, the configuration in which the analyzer 8 is rotationally moved about the rotation axis A has been described. However, the configuration is not limited to such a configuration, and a configuration in which the polarizer 7 is rotationally moved about a rotation axis orthogonal to the polarizer 7 may be used. Further, as long as the polarizer 7 and the analyzer 8 are relatively moved, the configuration may be such that both the polarizer 7 and the analyzer 8 are rotationally moved, or the polarizer 7 and the analyzer 8 may be moved. A configuration in which at least one of the photons 8 is moved in a mode other than rotation such as a slide may be employed.

(3) The moving mechanism for transitioning the polarizer 7 or the analyzer 8 between the orthogonal state, the parallel state, and the retracted state is not limited to a configuration including a driving source such as a motor like the rotating mechanism 9, but is a manual type. It may be. In this case, a lever for the operator to move the polarizer 7 or the analyzer 8 while holding the same may be provided in the moving mechanism.

(4) In the above embodiment, the case where the present invention is applied to the infrared microscope 100 has been described. However, the present invention is not limited to the infrared microscope 100, but is also applicable to a polarization microscope without the infrared light source 2.

DESCRIPTION OF SYMBOLS 1 Sample stage 2 Infrared light source 3 Visible light source 4 Detector 5 Camera 6 Beam splitter 7 Polarizer 8 Analyzer 9 Rotation mechanism 81 Disk 82 Notch 83 Main body 84 Holding part 85 Main body 86 Holding part 100 Infrared microscope

Claims (7)

A light source for irradiating the sample with light,
A polarizer that is disposed on an optical path from the light source to a sample and transmits light from the light source, so that a polarization plane generates linearly polarized light along a first direction,
An analyzer that is arranged on the optical path of the light after being irradiated on the sample, and whose polarization plane transmits linearly polarized light along the second direction;
By moving the polarizer and the analyzer relatively, a perpendicular state in which the first direction and the second direction are perpendicular to each other and a parallel state in which the first direction and the second direction extend in parallel. A polarizing microscope comprising: a moving mechanism capable of making a transition between a state and a retracted state in which the polarizer or the analyzer is not on an optical path.   The polarization microscope according to claim 1, wherein the moving mechanism rotates the polarizer or the analyzer around a rotation axis.   The polarization microscope according to claim 2, wherein the rotation axis passes through the center of gravity of the polarizer or the analyzer.   The polarizer or the analyzer transitions between the orthogonal state, the parallel state, and the retracted state by rotating at a rotation angle of 90 ° or more and less than 360 ° around the rotation axis. The polarizing microscope according to claim 2 or 3, wherein:   The polarizer or the analyzer has a shape having a notch in a part of a disk, and is in the retracted state when the notch is located on an optical path. The polarizing microscope according to any one of items 4 to 5. The light source includes a visible light source that emits visible light toward the sample, and an infrared light source that emits infrared light toward the sample,
The polarization microscope according to any one of claims 1 to 5, wherein the polarizer and the analyzer are arranged on an optical path of visible light emitted from the visible light source. The light source includes a visible light source that emits visible light toward the sample, and an infrared light source that emits infrared light toward the sample,
The polarization microscope according to any one of claims 1 to 5, wherein the polarizer and the analyzer are arranged on an optical path of infrared light emitted from the infrared light source.

Images