JP2018081134A - Microscope device, dark field illumination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microscope device allowing a dark field observation method to be performed in a high lighting efficiency, and a dark field illumination device.SOLUTION: A microscope device 10 comprises: an object lens 12 collecting light from a sample S; a plurality of light source parts 5 emitting an illumination light for dark field observation; a dark field illumination optical system 20 arranged outside the object lens 12, guiding the illumination light emitted from the plurality of light source parts 5 to the sample S to illuminate the sample S. The dark field illumination optical system 20 includes: a plurality of optical members parallel to an optical axis of the object lens 12 and arranged without contacting each other via air; a light guide part guiding the illumination light through the plurality of optical members; and a deflection part composed of a single member, deflecting the illumination light guided by the light guide part toward the optical axis to radiate the sample S.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a microscope apparatus that performs a dark field observation method and a dark field illumination apparatus.

  Conventionally, a dark field observation method is known which is an observation method in which light scattered on a specimen is captured by an objective lens by irradiating illumination light from the outside of the objective lens. Compared with the bright field observation method, the dark field observation method shows a clearer contrast due to the shape of the specimen, so it is effective when observing the fine structure on the specimen or observing the minute specimen. It can be said that it is a technique.

  Patent Document 1 describes a technique of irradiating a ring-shaped light beam from the outer peripheral side of an objective lens by using an illumination system in which a hollow cylindrical optical member is disposed in an outer peripheral region of the objective lens. According to this method, the illumination intensity can be improved by irradiating more illumination light.

Japanese translation of PCT publication No. 2002-507779

  In the dark field observation method, in order to observe the fine structure more clearly, it is necessary to illuminate the specimen with high illumination efficiency as well as illumination intensity. In Patent Document 1, although the illumination intensity is improved, light diverges in the circumferential direction in the hollow cylindrical optical member, and there is a possibility that the illumination light is not sufficiently collected at the observation position on the specimen.

  That is, in addition to the improvement in illumination intensity, a technique that can realize high illumination efficiency and perform a dark field observation method is desired.

  Therefore, an object of the present invention is to provide a microscope apparatus and a dark field illumination apparatus that can perform a dark field observation method with high illumination efficiency.

  A microscope apparatus according to an aspect of the present invention includes an objective lens that captures light from a specimen, a plurality of light source units that emit illumination light for dark field observation, and an optical system that is disposed outside the objective lens. A dark field illumination optical system that guides the illumination light emitted from the plurality of light source units to the specimen and illuminates the specimen, wherein the dark field illumination optical system is an optical axis of the objective lens A plurality of optical members that are arranged in parallel with each other and are not in contact with each other, and that guides the illumination light through the plurality of optical members, and is guided by the light guide unit. And a deflecting unit made of a single member that irradiates the specimen by deflecting the illuminated illumination light toward the optical axis.

  A dark field illumination device according to an aspect of the present invention includes a plurality of light source units that emit illumination light for dark field observation, and a plurality of optical members that are parallel to each other and are arranged in contact with each other with an air layer therebetween. A light guide unit that guides the illumination light emitted from the light source unit, and a deflecting unit that includes a single member that deflects the illumination light guided by the light guide unit. To do.

  According to the microscope device and the dark field illumination device of the present invention, the dark field observation method can be performed with high illumination efficiency.

The figure which shows the structure of the microscope apparatus in 1st Embodiment. The perspective view of the dark field illumination optical system in 1st Embodiment. The figure which looked at the dark field illumination optical system in a 1st embodiment from the side. The figure which looked at the dark field illumination optical system in a 1st embodiment from the light source side. The figure which shows the arrangement | positioning relationship between the light source part in 1st Embodiment, and an optical member. The figure which shows the arrangement | positioning relationship between the optical member and deflection | deviation part in 1st Embodiment, and the illumination area on a sample. The figure which shows the illumination intensity distribution on a sample plane when the sample is illuminated using the dark field illumination optical system in 1st Embodiment. The perspective view of the dark field illumination optical system by a prior art. The figure which looked at the dark field illumination optical system by a prior art from the side. The figure which looked at the dark field illumination optical system by a prior art from the light source side. The figure which shows the illumination intensity distribution on a sample plane when the sample is illuminated using the dark field illumination optical system by a prior art. The figure which shows the structure of the microscope apparatus by one modification. The figure which shows the structure of the microscope apparatus by another one modification. The perspective view of the dark field illumination optical system in 2nd Embodiment. The figure which looked at the dark field illumination optical system in 2nd Embodiment from the side. The figure which looked at the dark field illumination optical system in 2nd Embodiment from the light source side. The figure which shows the illumination intensity distribution on a sample plane when the sample top is illuminated using the dark field illumination optical system in 2nd Embodiment. The perspective view of the dark field illumination optical system in 3rd Embodiment. The figure which looked at the dark field illumination optical system in 3rd Embodiment from the side. The figure which looked at the dark field illumination optical system in 3rd Embodiment from the light source side. The figure which shows the illumination intensity distribution on a sample plane when the sample top is illuminated using the dark field illumination optical system in 3rd Embodiment. The figure which shows the illumination intensity distribution on a sample plane when the sample top is illuminated using the dark field illumination optical system in the modification of 3rd Embodiment. The perspective view of the dark field illumination optical system in 4th Embodiment. The figure which looked at the dark field illumination optical system in 4th Embodiment from the side. The figure which looked at the dark field illumination optical system in 4th Embodiment from the light source side. The figure which shows the illumination intensity distribution on a sample plane when the sample top is illuminated using the dark field illumination optical system in 4th Embodiment. The figure which shows the arrangement | positioning relationship between the light source part in 4th Embodiment, and an optical member. The perspective view of the dark field illumination optical system in 5th Embodiment. The figure which looked at the dark field illumination optical system in a 5th embodiment from the side. The figure which looked at the dark field illumination optical system in a 5th embodiment from the light source side. The figure which shows the illumination intensity distribution on a sample plane when the sample top is illuminated using the dark field illumination optical system in 5th Embodiment. The perspective view of the dark field illumination optical system in 6th Embodiment. The figure which looked at the dark field illumination optical system in 6th Embodiment from the side. The figure which looked at the dark field illumination optical system in 6th Embodiment from the light source side. The figure which shows the illumination intensity distribution on a sample plane when the sample top is illuminated using the dark field illumination optical system in 6th Embodiment.

  Hereinafter, the microscope apparatus 10 according to the first embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the configuration of the microscope apparatus 10. The microscope apparatus 10 is an epi-illumination type microscope apparatus provided with a dark field illumination light source and an optical system in order to perform a dark field observation method.

  The microscope apparatus 10 includes a light source unit 1 that emits illumination light for bright field observation, relay lenses 2 and 3, a half mirror 4, a plurality of light source units 5 that emit illumination light for dark field observation, A field illumination optical system 20, an objective lens 12, an imaging lens 6, a half mirror 7, an eyepiece lens 9, and a photodetector 11 are provided. The dark field illumination optical system 20 is an optical system disposed outside the objective lens, and guides illumination light from the plurality of light source units 5 and irradiates the specimen S.

  At the time of bright field observation, the illumination light emitted from the light source unit 1 is irradiated toward the specimen S through the relay lenses 2 and 3, the half mirror 4, and the objective lens 12. The objective lens 12 takes in the light reflected by the sample S and forms a primary image with the imaging lens 6. Here, the primary image reflected and formed by the half mirror 7 is projected to the user's pupil through the eyepiece 9. The light transmitted through the half mirror 7 is imaged by the photodetector 11 by the imaging lens 6.

  At the time of dark field observation, the illumination light emitted from the light source unit 5 is irradiated toward the sample S through the dark field illumination optical system 20. The objective lens 12 captures light scattered by the sample S. The subsequent transmission of light to the eyepiece 9 and the photodetector 11 is performed in the same manner as in bright field observation. Hereinafter, the configuration of the dark field illumination optical system 20 will be described in detail with reference to the drawings.

  FIG. 2 is a perspective view of the dark field illumination optical system 20. The dark field illumination optical system 20 includes a light guide unit 21 and a deflecting unit 22 arranged around the objective lens 12. The light guide unit 21 includes a plurality of optical members (optical members 21a, 21b,...) That are arranged in parallel with the optical axis of the objective lens and that are not in contact with each other and are spaced apart from each other. The medium in the plurality of optical members is formed of a known light guide material having a refractive index higher than that of air, for example, acrylic.

  The plurality of optical members have the same shape as each other, with an end surface A that is an incident surface of illumination light positioned on the light source unit 5 side and an exit surface of the guided illumination light that is positioned on the deflection unit 22 side. It is constituted by a certain end surface B and a side surface C. The plurality of optical members are formed in a columnar shape, and each cross-sectional shape is a circle. The rotational symmetry axis extending in the longitudinal direction of the columnar shapes of the plurality of optical members is parallel to the optical axis of the objective lens.

  The light guide unit 21 guides illumination light through a plurality of optical members. More specifically, the light guide unit 21 guides the illumination light incident from the end surface A on the light source unit 5 side of each of the plurality of optical members by reflecting the light inside the optical member, and the end surface B on the deflection unit 22 side. To the deflection unit 22. At this time, since the medium of the optical member is higher than the refractive index of the external air, the reflection angle of the illumination light is not less than the critical angle on the side surface C, and light does not leak outside from the side surface C due to total reflection.

  The deflecting unit 22 deflects the illumination light guided by the light guide unit 21 in the direction of the optical axis of the objective lens 12, that is, irradiates the sample S by deflecting the illumination light in the direction toward the optical axis. And is formed from a single member. The deflecting unit 22 is preferably configured to match the numerical aperture of the objective lens 12 to be used. For example, when using a high numerical aperture objective lens with a short working distance, it is necessary to increase the concentration of illumination light in order to collect light in a narrow range. In such a case, it is preferable to increase the concentration of illumination light by using an annular mirror as the deflecting unit 22. Conversely, when using a low numerical aperture objective lens with a long working distance, it is necessary to focus light over a wide range. In such a case, by using an annular lens as the deflecting unit 22, light can be condensed over a wider range than the above-described annular mirror. The refractive power of the annular lens may be appropriately adjusted according to the objective lens 12 to be used. The lens used as the annular lens may be, for example, a Fresnel lens. 2 is a lens in which the specimen S side is a plane and the light source side is a convex surface when viewed in a cross section including the optical axis of the objective lens 12, and the optical axis of the objective lens 12 coincides with the axis center. It is formed of an annular lens having a cylindrical shape that is hollowed out.

  FIG. 3 is a view of the dark field illumination optical system 20 as viewed from the side. FIG. 4 is a view of the dark field illumination optical system 20 as viewed from the light source 5 side. In FIG. 3, the description of the mechanical frame that houses the dark field illumination optical system 20 is omitted.

In FIG. 3, R1 to R4 indicate the radii of curvature of the respective parts. Moreover, T1-T3 in FIG. 3 and D1-D4 in FIG. 4 show the length of each part, respectively. More specifically, R1, R2, R3, and R4 are the radius of curvature of the optical member incident end face, the radius of curvature of the optical member exit end face, the radius of curvature of the deflector entrance end face, and the radius of curvature of the deflector exit end face, respectively. T1, T2, and T3 are the length of the optical member that is the length from the optical member incident end surface to the optical member output end surface, the deflection unit length that is the length from the deflection unit incident end surface to the deflection unit output end surface, and the deflection unit output, respectively. The length from the end surface to the sample surface. D1, D2, D3, and D4 are a light source section moving diameter, an optical member outer diameter, a deflection section inner radius, and a deflection section outer radius, which are distances from the optical axis of the objective lens 12 to the light source section, respectively. Refer to the following Table 1 for each numerical value of R1 to R4, T1 to T3, and D1 to D4. The units of T1 to T3 and D1 to D4 are all in millimeters.

  According to the microscope apparatus 10 including the dark field illumination optical system 20 having the above configuration, the dark field observation method can be performed with high illumination efficiency by guiding the illumination light through the plurality of optical members. In particular, in the dark field illumination optical system 20, for the plurality of optical members that guide the illumination light from the light source unit 5, by changing the length in the optical axis direction of each optical member and the optical member outer diameter at the time of design, The distribution of the illumination light on the exit end face of each optical member can be easily adjusted, and consequently the area irradiated on the sample S can be adjusted. Therefore, the illumination light from the light source unit 5 does not diverge while being guided, and it is possible to prevent a situation in which the illumination light is irradiated to an unintended region on the specimen S, thereby improving the illumination efficiency. Can be achieved.

  In addition, the plurality of optical members are made of a single material having a refractive index larger than the refractive index of air so that a critical angle can be formed inside the optical member and the reflected light can be totally reflected. Has been. Therefore, manufacture and assembly can be easily performed as compared with a configuration in which an optical member is formed by a plurality of media.

  Further, the dark field illumination optical system 20 is composed of an optical member composed of a single medium and a deflecting unit 22 composed of a single member, so that the assemblability is good. Therefore, even when the objective lens 12 having a different numerical aperture is used, only the length in the optical axis direction of the plurality of optical members, the optical member diameter, and the configuration of the deflecting unit 22 are changed according to the objective lens to be used. A dark field illumination optical system 20 suitable for observation can be prepared.

  Hereinafter, a more desirable configuration of the dark field illumination optical system 20 will be described.

  Each of the plurality of optical members included in the light guide unit 21 has a cross-sectional shape that is a circle or a regular polygon in a plane perpendicular to the optical axis of the objective lens 12, and the optical axis direction of the objective lens 12 is It is desirable to have similar or congruent cross-sectional shapes at different positions. Since the cross-sectional shape is a circle or a regular polygon, the illumination light guided in each of the plurality of optical members has an isotropic light distribution characteristic. Therefore, an isotropic illuminance distribution is formed in the illumination area by the illumination light emitted from the emission end face B of each optical member to the specimen S, and illumination unevenness can be reduced. Moreover, the magnitude | size of the illumination distribution of the optical member output end surface B can be adjusted by adjusting an optical member outer diameter suitably. Therefore, by matching the size of the illumination distribution of the optical member emitting end face B with the field of view on the sample S, the illumination light from the light source unit 5 is diverged and irradiated outside the field of view of the objective lens 12. It is possible to suppress.

  In addition, it is desirable that the plurality of optical members included in the light guide unit 21 be disposed rotationally symmetrically with respect to the optical axis of the objective lens 12. In general, when illumination light from a specific direction or illumination light having a strong intensity in a specific direction component is irradiated, the uneven shape of the sample S has a shadow derived from that direction. On the other hand, by arranging a plurality of optical members in a rotationally symmetrical manner in the configuration of the light guide section 21, the unevenness of the direction component of the illumination light is reduced, and the uneven shape of the sample S has a shadow derived from a specific direction. Can be suppressed. As a result, the same image as in general indoor / indoor lighting can be obtained. In particular, since the plurality of optical members are arranged at the same diameter and the same pitch, the effect of reducing the deviation of the direction component of the illumination light is achieved.

  Further, by arranging the plurality of light source units 5 to be rotationally symmetrical with respect to the optical axis of the objective lens 12, the optical path lengths to the samples S of the illumination light emitted from each of the plurality of light source units 5 are substantially equal. Irradiation unevenness can be reduced.

  The plurality of optical members included in the light guide unit 21 are columnar in the present embodiment, but are formed in a frustum shape having a spread on the sample S side or a frustum shape having a spread on the light source unit 5 side. It may be. Although the illumination efficiency can be further improved by appropriately selecting the above configuration according to the numerical aperture of the objective lens 12 to be used, such a configuration will be described in an embodiment described later. Even if the cross-sectional shape is similar at each position where the optical axis direction of the objective lens 12 is different, the isotropy of the illuminance distribution on the sample S is maintained.

  Moreover, it is desirable that the end surfaces A and B forming the plurality of optical members of the light guide portion 21 have a shape that allows light to enter and exit uniformly. For example, the end surfaces A and B are either flat surfaces, spherical surfaces, or conic surfaces. It is formed. In particular, the end faces A and B have a function of condensing illumination light to the illumination area by making the end faces A and B spherical or conic and adjusting the radius of curvature. For example, even when it is desired to illuminate a narrower illumination area, the condensing power of the illumination light can be increased by making the end faces A and B have a spherical shape or a conic surface shape with an appropriate curvature radius.

In addition, each of the plurality of optical members of the light guide unit 21 may be formed of a single plastic material. By making the optical member plastic, the assemblability of the dark field illumination optical system 20 is improved. For example, the plurality of optical members of the light guide unit 21 may be optical fibers.
Further, for each of the plurality of optical members of the light guide unit 21, the emission end face of the optical member may have an angle with respect to the surface of the sample S. That is, the emission end face of the optical member is not limited to a shape parallel to the surface of the sample S. For example, since the emission end face has an angle so that the emission end face of the optical member is directed to the field area of the objective lens 12, more light reaches the field area, so that the illumination efficiency can be improved.

  In addition, each of the plurality of optical members of the light guide unit 21 is arranged in parallel with the optical axis of the objective lens 12, but the light guide path between the incident end surface and the output end surface of the optical member is the optical axis of the objective lens 12. The shape may have an angle with respect to the direction. Since the light guide path has an angle, the position of the illumination distribution on the light exit end face of the optical member is changed, and the position of the illumination area on the sample S is changed. Thus, the position of the illumination area may be finely adjusted by forming the light guide paths of the plurality of optical members at an angle in advance.

Hereinafter, a more desirable arrangement of the light source unit 5, the light guide unit 21, and the deflection unit 22 will be described with reference to the drawings. FIG. 5 is a diagram illustrating an arrangement relationship between one light source unit in the light source unit 5 and one optical member (here, the optical member 21 a as a representative) among the optical members included in the light guide unit 21. In FIG. 5, d, θ, D, and H represent the light source part diameter, the light distribution angle, the optical member outer diameter, and the length from the light source end part to the light guide part incident surface, respectively. Here, it is desirable that the following conditional expression is satisfied in order for the illumination light from the light source unit to pass through all incident ends of the optical member 21a.

  The conditional expression is derived from the condition that the outer diameter D of the optical member is larger than the diameter of the irradiation range of the illumination light emitted from the light source part having the light source part diameter d.

  Further, as a conventional technique, there is a configuration in which light emitted from the light source unit is relayed toward a condensing lens for condensing the sample S through a collimator lens. On the other hand, the distance between the light source unit and the collimating lens is limited by the focal length of the collimating lens to be used. On the other hand, in the microscope apparatus 10 of the present embodiment, the distance between the light source unit 5 and the light guide unit 21 depends on the design of the outer diameter of the light guide unit 21 as shown in the conditional expression [Equation 1]. Can be arbitrarily adjusted. Therefore, the freedom degree of arrangement | positioning in an apparatus can be made high.

  FIG. 6 is a diagram illustrating an arrangement relationship between one optical member (here, the optical member 21 a as a representative) and the deflecting unit 22 among the optical members included in the light guide unit 21 and the illumination region on the specimen S. In FIG. 6, θ, D, r, and WD are the light distribution angle of the light source unit 5, the optical member outer diameter, the distance from the central axis of the optical member to the optical axis of the objective lens 12, and the working distance of the objective lens 12. is there.

At this time, l, which is the distance from the center of the exit end face of the deflecting unit 22 in FIG. 6 to the center of the illumination area, is expressed by the following relational expression using r and WD.

Further, the radius a of the region where the illumination light irradiated at the light source light distribution angle θ from the center of the emission end of the deflecting unit 22 in FIG. 6 is irradiated on the sample S is expressed by the following relational expression using l. The Note that φ represents an angle of a line connecting the center of the emission end face of the deflecting unit 22 to the contact point between the optical axis of the objective lens 12 and the sample S with respect to the optical axis of the objective lens 12.

  From the above, the diameter of the illumination area defined in FIG. 6 is a value obtained by adding D to 2a. The illumination area here refers to an area irradiated with illumination light through the dark field illumination optical system 20.

On the other hand, depending on the shape of the end face of the optical member (end faces A and B), the light distribution angle of the illumination light on the emission end face side of the optical member can be narrower than the light distribution angle of the light source unit 5. Moreover, the area irradiated with illumination light can be narrowed by the cross-sectional shape of the optical member. Therefore, the illumination area can be further narrowed by the shape and cross-sectional shape of the end face of the optical member with respect to the illumination area defined by FIG. 6. Therefore, when the diameter of the illumination area is f, f is in a range satisfying the following conditional expression. It should be decided.

  Moreover, in order to ensure the working distance WD of the objective lens 12, it is desirable to adjust the arrangement as follows. The total length of the plurality of optical members included in the light guide unit 21 and the thickness of the deflecting unit 22 is equal to or less than the distance obtained by subtracting the working distance WD of the objective lens 12 from the distance from the light source unit 5 to the sample S. It is desirable that

  FIG. 7 is a diagram showing an illuminance distribution corresponding to a position on the specimen S plane perpendicular to the optical axis of the objective lens 12 when the specimen S is illuminated using the dark field illumination optical system 20. A region F surrounded by an alternate long and short dash line indicates a visual field region of the objective lens 12. Thus, it can be seen that the illumination light is uniformly irradiated in the region F by performing illumination using the dark field illumination optical system 20.

  Hereinafter, as a comparative example of the microscope apparatus 10 of the first embodiment, a dark field illumination optical system 30 including a hollow cylindrical light guide unit, which is a conventional technique, is replaced with a dark field illumination optical system 20 of the microscope apparatus 10. The effect of the arrangement instead will be described with reference to the drawings.

  FIG. 8 is a perspective view of the dark field illumination optical system 30. The dark field illumination optical system 30 includes a light guide unit 31 made of a single hollow cylindrical optical member and a deflection unit 32.

  FIG. 9 is a view of the dark field illumination optical system 30 as viewed from the side. FIG. 10 is a view of the dark field illumination optical system 30 as viewed from the light source unit side.

In FIG. 9, R1 to R4 indicate the radii of curvature of the respective parts. Further, T1 to T3 in FIG. 9 and D1 to D4 in FIG. 10 indicate the length of each part, respectively. More specifically, R1, R2, R3, and R4 are the radius of curvature of the optical member incident end face, the radius of curvature of the optical member exit end face, the radius of curvature of the deflector entrance end face, and the radius of curvature of the deflector exit end face, respectively. T1, T2, and T3 are an optical member length, a deflection unit length, and a length from the deflection unit emission end surface to the sample surface, respectively. D1, D2, D3, and D4 are a light source portion moving diameter, an optical member outer diameter, a deflection portion inner radius, and a deflection portion outer radius, respectively. Refer to the following Table 2 for each numerical value of R1 to R4, T1 to T3, and D1 to D4. The units of T1 to T3 and D1 to D4 are all in millimeters.

  An illuminance distribution corresponding to a position on the sample S plane perpendicular to the optical axis of the objective lens 12 when the sample S is illuminated by the microscope apparatus 40 including the dark field illumination optical system 30 having the above configuration is shown in FIG. 11 and so on. A region F surrounded by an alternate long and short dash line indicates a visual field region of the objective lens 12. In FIG. 7, a part of the illumination light irradiated with the illumination light in the region F is irradiated outside the region F in FIG. 11. That is, in FIG. 11, it can be seen that the illumination light is also irradiated outside the illumination area of FIG. It is considered that this occurs because light diverges in the circumferential direction in the circumferential direction in the hollow cylindrical optical member, and illumination light is not guided onto the illumination region that should be guided.

  As described above, as can be seen by comparing FIG. 11 and FIG. 7, the dark field observation performed using the dark field illumination optical system 20 is compared with the dark field observation performed using the dark field illumination optical system 30 according to the prior art. It can be seen that the lighting efficiency can be improved.

  Next, as a modification of the first embodiment, the following apparatus configuration can be cited.

  FIG. 12 is a diagram illustrating a configuration of the microscope apparatus 40 according to the first modification. The microscope apparatus 40 includes dark field illumination optical systems 20a and 20b. In addition, the microscope apparatus 40 includes a plurality of light source units 5a that allow illumination light to enter the dark field illumination optical system 20a and a plurality of light source units 5b that allow illumination light to enter the dark field illumination optical system 20b. ing. The dark field illumination optical systems 20a and 20b are designed under conditions that match the numerical aperture of the objective lens used in advance. When the objective lens 12 to be used is mounted, the dark field illumination optical systems 20a and 20b are switched and arranged below the corresponding light source unit.

  As described above, assuming that a plurality of objective lenses having different numerical apertures are used, a plurality of dark field illumination optical systems (dark field illumination optical systems 20a and 20b) may be switchably arranged. In addition, by including the light source units 5a and 5b in the microscope apparatus 40, it is possible to switch a plurality of dark field illumination optical systems without removing the light source unit, and the operability at the time of switching is good.

  FIG. 13 is a diagram illustrating a configuration of a microscope apparatus 45a according to the second modification. The microscope device 45a includes a dark field illumination device 45b that is detachable. The dark field illumination device 45b includes the light source unit 5 for dark field illumination, and is described as a dark field illumination device because it can perform dark field illumination alone, but includes the light source unit 5. Except for this point, the configuration is the same as that of the dark field illumination optical system 20 in the first embodiment. More specifically, the dark field illumination device 45b includes a plurality of light source units 5 that emit illumination light for dark field observation and a plurality of light source units 5 that are arranged in parallel with each other and are not in contact with each other and are separated from the air. A light guide unit that guides the illumination light emitted from the light source, and a deflecting unit that includes a single member that deflects the illumination light guided by the light guide unit.

  That is, the microscope apparatus 45 is configured such that the light source unit 5 for dark field illumination is externally attached, and the same effect as the microscope apparatus 10 of the first embodiment can be obtained in this configuration.

  Hereinafter, the configuration of the dark field illumination optical system 50 in the microscope apparatus according to the second embodiment will be described. Since the configuration of the microscope apparatus according to the second embodiment is the same as that of the microscope apparatus 10, the description thereof is omitted.

  FIG. 14 is a perspective view of the dark field illumination optical system 50. The dark field illumination optical system 50 includes a light guide unit 51 including a plurality of optical members (optical members 51a, 51b,...) And a deflection unit 52. The light guide 51 has the same configuration as the light guide 21 of the dark field illumination optical system 20. The deflection unit 52 is configured by an annular mirror. Note that the description of the mechanical frame that houses the dark field illumination optical system 20 is omitted.

  FIG. 15 is a view of the dark field illumination optical system 50 as viewed from the side. FIG. 16 is a diagram of the dark field illumination optical system 50 as viewed from the light source unit 5 side.

In FIG. 15, R1 and R2 indicate the radii of curvature of the respective parts. Further, T1 to T3 in FIG. 15 and D1 to D4 in FIG. 16 indicate the length of each part, respectively. More specifically, R1 and R2 are the radius of curvature of the optical member entrance end face and the radius of curvature of the optical member exit end face, respectively. T1, T2, and T3 are the length of the optical member, the length of the deflecting portion, and the length from the exit end surface of the deflecting portion to the sample surface, respectively. D1, D2, D3, and D4 are a light source portion moving diameter, an optical member outer diameter, a deflection portion inner radius, and a deflection portion outer radius, respectively. Refer to Table 3 below for the numerical values of R1, R2, T1 to T3, and D1 to D4. The units of T1 to T3 and D1 to D4 are all in millimeters.

  Even with a microscope apparatus including the dark field illumination optical system 50 having the above configuration, the dark field observation method can be performed with high illumination efficiency. In particular, when a high numerical aperture objective lens with a short working distance is used, it is possible to increase the concentration of illumination light by using an annular mirror as the deflecting unit 51 as in this configuration.

  FIG. 17 is a diagram showing an illuminance distribution corresponding to a position on the specimen S plane perpendicular to the optical axis of the objective lens of the microscope apparatus when the specimen S is illuminated using the dark field illumination optical system 50. A region F surrounded by an alternate long and short dash line indicates a visual field region of the objective lens 12. Thus, it can be seen that the illumination light is uniformly irradiated in the region F by performing illumination using the dark field illumination optical system 50.

  Hereinafter, the configuration of the dark field illumination optical system 60 in the microscope apparatus according to the third embodiment will be described. In the microscope apparatus according to the third embodiment, the arrangement of the plurality of light source units 5 is rotationally symmetric with respect to the optical axis of the objective lens 12, which is the same as the feature described in the first embodiment. It differs from the microscope apparatus 10 in that the arrangement of the light source unit 5 is adapted to the arrangement of optical members described later.

  FIG. 18 is a perspective view of the dark field illumination optical system 60. FIG. 19 is a diagram of the dark field illumination optical system 60 viewed from the side. FIG. 20 is a diagram of the dark field illumination optical system 60 as viewed from the light source unit 5 side. The dark field illumination optics 60 includes a light guide unit 61 including a plurality of optical members and a deflecting unit 62. The deflecting unit 62 has the same configuration as the deflecting unit 22 of the dark field illumination optical system 20.

  The plurality of optical members included in the light guide unit 61 are arranged in a rotationally symmetrical manner with respect to the optical axis of the objective lens of the microscope apparatus, which is the same as the feature described in the first embodiment. On the other hand, the plurality of optical members included in the light guide unit 61 are rotationally symmetrically arranged on a plurality of circumferences having different moving diameters around the optical axis of the objective lens.

  As shown in FIG. 20, when the four optical members 61a to 61d are grouped, it can be said that the groups corresponding to the arrangement of the four optical members 61a to 61d are arranged rotationally symmetrically. At this time, illumination light from the light source unit 5e passes through a central region surrounded by the four optical members 61a to 61d. That is, the illumination light from the light source unit 5e is guided through the outer peripheral surfaces of the four optical members 61a to 61d. Moreover, the light source parts 5a-5d of FIG. 20 are light-guided via the optical members 61a-61d, respectively.

In FIG. 19, R <b> 1 to R <b> 4 indicate the radius of curvature of each part. Moreover, T1-T3 in FIG. 19 and D1-D4 in FIG. 20 show the length of each part, respectively. More specifically, R1, R2, R3, and R4 are the radius of curvature of the optical member incident end face, the radius of curvature of the optical member exit end face, the radius of curvature of the deflector entrance end face, and the radius of curvature of the deflector exit end face, respectively. T1, T2 and T3 are the length of the optical member, the length of the deflection section, and the length from the exit end face of the deflection section to the sample surface, respectively. D1, D2, D3, and D4 are a light source portion moving diameter, an optical member outer diameter, a deflection portion inner radius, and a deflection portion outer radius, respectively. Refer to the following Table 4 for the numerical values of R1 to R4, T1 to T3, and D1 to D4. The units of T1 to T3 and D1 to D4 are all in millimeters.

  Even with a microscope apparatus including the dark field illumination optical system 60 having the above configuration, the dark field observation method can be performed with high illumination efficiency. In this way, the illuminance can be improved by increasing the number of optical members and the light source units 5 arranged in a rotationally symmetrical manner.

  FIG. 21 is a diagram showing an illuminance distribution corresponding to a position on the specimen S plane perpendicular to the optical axis of the objective lens of the microscope apparatus when the specimen S is illuminated using the dark field illumination optical system 60. A region F surrounded by an alternate long and short dash line indicates a visual field region of the objective lens 12. Thus, it can be seen that the illumination light is uniformly irradiated in the region F by performing illumination using the dark field illumination optical system 60.

  FIG. 22 shows the position on the specimen S plane in the dark field illumination optical system 60 except for the light source part (light source part 5e and the like) that emits illumination light guided through the outer peripheral surfaces of the four optical members. It is a figure which shows the illumination intensity distribution corresponding to. Compared with the illuminance distribution of FIG. 21, the illuminance slightly decreases, but it can be seen that the illumination light is evenly irradiated in the region F in FIG. 22. In this way, the configuration may be such that there is no light source unit (light source unit 5e or the like) that emits illumination light guided through the outer peripheral surfaces of the four optical members.

  Hereinafter, the configuration of the dark field illumination optical system 70 in the microscope apparatus according to the fourth embodiment will be described. In the microscope apparatus according to the fourth embodiment, the arrangement of the plurality of light source units 5 is rotationally symmetric with respect to the optical axis of the objective lens 12, which is the same as the feature described in the first embodiment. It differs from the microscope apparatus 10 in that the arrangement of the light source unit 5 is adapted to the arrangement of optical members described later.

  FIG. 23 is a perspective view of the dark field illumination optical system 70. FIG. 24 is a diagram of the dark field illumination optical system 70 viewed from the side. FIG. 25 is a view of the dark field illumination optical system 60 as viewed from the light source unit 5 side. The dark field illumination optics 70 includes a light guide unit 71 including a plurality of optical members (optical members 71a, 71b...) And a deflecting unit 72. The deflecting unit 72 has the same configuration as the deflecting unit 22 of the dark field illumination optical system 20.

  Description will be made by paying attention to one optical member 71a among the plurality of optical members. As shown in FIG. 25, the area of the incident end surface of the illumination light in the optical member 71a is configured to be larger than the area of each light source unit, and from the light source units 5a to 5e among the plurality of light source units. The illumination light is configured to enter the end face of the optical member 71a. That is, the optical member 71a is configured to guide illumination light from a plurality of light source units. The sizes of the other optical members and the relationship between the optical members and the light source units are the same as those of the optical member 71a.

  Moreover, the light source parts 5a-5e are arrange | positioned rotationally symmetrically about the central axis of the cross-sectional shape of the optical member 71a. The same applies to the other optical members, that is, each of the plurality of light source units is arranged rotationally symmetrically with respect to the central axis of the cross-sectional shape of any one of the plurality of optical members. Moreover, the number of the light source parts arrange | positioned rotationally symmetrically about the central axis of the cross-sectional shape of an optical member may be changed suitably.

In FIG. 24, R1 to R4 indicate the radii of curvature of the respective parts. Moreover, T1-T3 in FIG. 24 and D1-D4 in FIG. 25 show the length of each part, respectively. More specifically, R1, R2, R3, and R4 are the radius of curvature of the optical member incident end face, the radius of curvature of the optical member exit end face, the radius of curvature of the deflector entrance end face, and the radius of curvature of the deflector exit end face, respectively. T1, T2, and T3 are the length of the optical member, the length of the deflecting portion, and the length from the exit end surface of the deflecting portion to the sample surface, respectively. D1, D2, D3, and D4 are a light source portion moving diameter, an optical member outer diameter, a deflection portion inner radius, and a deflection portion outer radius, respectively. Refer to the following Table 5 for the numerical values of R1 to R4, T1 to T3, and D1 to D4. The units of T1 to T3 and D1 to D4 are all in millimeters.

  Even with a microscope apparatus including the dark field illumination optical system 70 having the above configuration, the dark field observation method can be performed with high illumination efficiency. When a wide field of view on the specimen S is to be observed using an objective lens having a low numerical aperture, it is necessary to irradiate more illumination light than when observing a narrow field of view. According to this configuration, since a plurality of light source units are arranged within the outer diameter of the end face of the optical member of the light guide unit 71, brightness is ensured in a wide visual field region on the specimen S without enlarging the device. be able to.

  In addition, each of the plurality of light source units is arranged rotationally symmetrically with respect to the central axis of the cross-sectional shape of any one of the plurality of optical members, thereby causing uneven distribution of illumination light on the light exit end surface of the light guide unit. Therefore, it is possible to reduce uneven illumination on the specimen S.

  FIG. 26 is a diagram showing an illuminance distribution corresponding to a position on the specimen S plane perpendicular to the optical axis of the objective lens of the microscope apparatus when the specimen S is illuminated using the dark field illumination optical system 70. A region F surrounded by an alternate long and short dash line indicates a visual field region of the objective lens 12. Thus, it can be seen that the illumination light is uniformly irradiated in the region F by performing illumination using the dark field illumination optical system 70.

A desirable arrangement of the plurality of light source units, the light guide unit 71, and the deflection unit 72 in the fourth embodiment will be described with reference to the drawings. FIG. 27 is a diagram showing an arrangement relationship between a plurality of light source units (three light source units in the drawing) and one optical member (here, the optical member 71a as a representative) among optical members included in the light guide unit 71. It is. In FIG. 27, d, θ, D, H, and P are the light source part diameter, the light distribution angle, the optical member outer diameter, the length from the light source end part to the optical member incident end face, and the distance connecting the two light source part centers. Among these, the distance between two points that are the farthest point pair. Here, it is desirable that the following conditional expression is satisfied in order for the illumination light from the light source unit to pass through all the incident ends of the optical member 71a.

  In addition, the said conditional expression is guide | induced from the conditions that the optical member outer diameter D is larger than the diameter of the irradiation range of the illumination light inject | emitted from the light source part of the light source part diameter d arranged in multiple numbers.

  Hereinafter, the configuration of the dark field illumination optical system 80 in the microscope apparatus according to the fifth embodiment will be described. Since the configuration of the microscope apparatus in the fifth embodiment is the same as the configuration of the microscope apparatus described in the fourth embodiment, the description thereof is omitted.

  FIG. 28 is a perspective view of the dark field illumination optical system 80. FIG. 29 is a diagram of the dark field illumination optical system 80 as seen from the side. FIG. 30 is a diagram of the dark field illumination optical system 80 as viewed from the light source unit 5 side. The dark field illumination optics 80 includes a light guide unit 81 including a plurality of optical members (optical members 81a, 81b...) And a deflecting unit 82. The deflection unit 82 has the same configuration as the deflection unit 22 of the dark field illumination optical system 20.

  The area of the incident end face of the illumination light in the plurality of optical members included in the light guide unit 81 is configured to be larger than the area of each light source unit, and each of the plurality of light source units is a plurality of optical members. The rotationally symmetrical arrangement with respect to the central axis of the cross-sectional shape of any one of the optical members is the same as the characteristics of the plurality of optical members included in the light guide unit 71 in the fourth embodiment.

  On the other hand, the plurality of optical members included in the light guide unit 81 are formed in a frustum shape. More specifically, as shown in FIG. 28 and FIG. 29, the optical member is formed in a frustum shape in which the cross-sectional shape of the optical member becomes narrower as it goes from the light source unit 5 side to the deflection unit 82 side. The According to such a shape, the reflection angle of the illumination light incident on the optical member from the light source unit side becomes larger as total reflection is repeated in the optical member. Therefore, the light distribution angle of the illumination light irradiated from the emission end of the optical member is larger than the light distribution angle in the light source unit, and an illuminance distribution suitable for illuminating a wide range on the sample S can be realized.

  On the contrary, the illumination irradiated from the light emitting end of the optical member by forming a frustum shape in which the cross-sectional shape of the optical member expands from the light source unit 5 side to the deflection unit 82 side of the plurality of optical members. The light distribution angle can be made smaller than the light distribution angle in the light source unit, and an illuminance distribution suitable for illuminating a narrow range on the sample S can also be realized.

In FIG. 29, R1 to R4 indicate the radii of curvature of the respective parts. Further, T1 to T3, D2a, and D2b in FIG. 29 and D1, D3, and D4 in FIG. 30 indicate the lengths of the respective parts. More specifically, R1, R2, R3, and R4 are the radius of curvature of the optical member incident end face, the radius of curvature of the optical member exit end face, the radius of curvature of the deflector entrance end face, and the radius of curvature of the deflector exit end face, respectively. T1, T2 and T3 are the length of the optical member, the length of the deflection section, and the length from the exit end face of the deflection section to the sample surface, respectively. D1, D2a, D2b, D3, and D4 are the light source section moving diameter, the outer diameter of the optical member entrance end face, the outer diameter of the optical member exit end face, the deflection section inner radius, and the deflection section outer radius, respectively. Refer to the following Table 6 for each numerical value of R1 to R4, T1 to T3, and D1 to D4. The units of T1 to T3 and D1 to D4 are all in millimeters.

  Even with a microscope apparatus including the dark field illumination optical system 80 having the above configuration, the dark field observation method can be performed with high illumination efficiency. Further, the plurality of optical members of the light guide unit 81 are formed in a frustum shape whose cross-sectional shape becomes narrower as it goes from the light source unit 5 side to the deflecting unit 82 side. A wide range can be illuminated.

  FIG. 31 is a diagram showing an illuminance distribution corresponding to a position on the specimen S plane perpendicular to the optical axis of the objective lens of the microscope apparatus when the specimen S is illuminated using the dark field illumination optical system 80. A region F surrounded by an alternate long and short dash line indicates a visual field region of the objective lens 12. Thus, it can be seen that the illumination light is uniformly irradiated in the region F by performing illumination using the dark field illumination optical system 80.

  Hereinafter, the configuration of the dark field illumination optical system 90 in the microscope apparatus according to the sixth embodiment will be described. Since the configuration of the microscope apparatus in the sixth embodiment is the same as that of the microscope apparatus described in the fourth embodiment, the description thereof is omitted.

  FIG. 32 is a perspective view of the dark field illumination optical system 90. FIG. 33 is a diagram of the dark field illumination optical system 90 viewed from the side. FIG. 34 is a diagram of the dark field illumination optical system 90 as viewed from the light source unit 5 side. The dark field illumination optical 90 includes a light guide unit 91 including a plurality of optical members (optical members 91a, 91b...) And a deflecting unit 92. The deflecting unit 92 has the same configuration as the deflecting unit 22 of the dark field illumination optical system 20.

  The plurality of optical members included in the light guide unit 91 have the same characteristics as the plurality of optical members of the light guide unit 71 in the fourth embodiment, except that the cross-sectional shape thereof is a regular square.

In FIG. 33, R1 to R4 indicate the radii of curvature of the respective parts. Moreover, T1-T3 in FIG. 33 and D1-D4 in FIG. 34 show the length of each part, respectively. More specifically, R1, R2, R3, and R4 are the radius of curvature of the optical member incident end face, the radius of curvature of the optical member exit end face, the radius of curvature of the deflector entrance end face, and the radius of curvature of the deflector exit end face, respectively. T1, T2 and T3 are the length of the optical member, the length of the deflection section, and the length from the exit end face of the deflection section to the sample surface, respectively. D1, D2, D3, and D4 are a light source portion moving diameter, an optical member outer diameter, a deflection portion inner radius, and a deflection portion outer radius, respectively. Refer to Table 7 below for the numerical values of R1 to R4, T1 to T3, and D1 to D4. The units of T1 to T3 and D1 to D4 are all in millimeters.

  Even with a microscope apparatus including the dark field illumination optical system 90 having the above configuration, the dark field observation method can be performed with high illumination efficiency. In this configuration, the cross-sectional shape of the plurality of optical members included in the light guide unit 91 is a regular square. However, as described in the first embodiment, the illumination region on the sample S is a circle or a regular polygon. Isotropic illuminance distribution is formed, and uneven illumination can be reduced.

  FIG. 35 is a diagram showing an illuminance distribution corresponding to a position on the specimen S plane perpendicular to the optical axis of the objective lens of the microscope apparatus when the specimen S is illuminated using the dark field illumination optical system 90. FIG. A region F surrounded by an alternate long and short dash line indicates a visual field region of the objective lens 12. Thus, it can be seen that the illumination light is uniformly irradiated in the region F by performing illumination using the dark field illumination optical system 90.

  The embodiments described above are specific examples for facilitating the understanding of the invention, and the present invention is not limited to these embodiments. The above-described microscope apparatus and dark field illumination apparatus can be variously modified and changed without departing from the scope of the present invention described in the claims.

10, 40, 45a Microscope device 20, 20a, 30, 50, 60, 70, 80, 90 Dark field illumination optical system 45b Dark field illumination device 1, 5 Light source unit 2, 3 Relay lens 4, 7 Half mirror 6 Imaging Lens 9 Eyepiece 11 Photodetector 12 Objective lenses 21, 31, 51, 61, 71, 81, 91 Light guide portions 21a, 21b, 51a, 51b, 61a,
61b, 61c, 61d, 71a, 71b Optical members 22, 32, 52, 62, 72, 82, 92 Deflection parts 5a, 5b, 5c, 5d, 5e Light source part A, B End face C Side face D Optical member outer diameter F region S Specimen r Optical member moving radius d Light source diameter R1, R2, R3, R4 Curvature radius D1, D2, D2a, D2b, D3, D4,
P, T1, T2, T3, H, a, l, f Distance θ, φ Angle

Claims (11)

An objective lens that captures light from the specimen;
A plurality of light source units for emitting illumination light for dark field observation;
An optical system arranged outside the objective lens, comprising: a dark field illumination optical system that guides the illumination light emitted from the plurality of light source units to the specimen and illuminates the specimen;
The dark field illumination optical system includes:
A light guide part that is parallel to the optical axis of the objective lens and includes a plurality of optical members that are arranged in contact with each other without contacting each other, and that guides the illumination light through the plurality of optical members;
A microscope apparatus comprising: a deflecting unit including a single member that irradiates the specimen by deflecting the illumination light guided by the light guiding unit toward the optical axis. The microscope apparatus according to claim 1,
Each of the plurality of optical members has a cross-sectional shape that is a circle or a regular polygon in a plane perpendicular to the optical axis of the objective lens, and the cross-sectional shape is similar or different at different positions in the optical axis direction. A microscope apparatus characterized by being congruent. The microscope apparatus according to claim 2,
Each of the plurality of optical members has a columnar shape or a frustum shape. The microscope apparatus according to claim 2 or claim 3, wherein
The microscope apparatus, wherein the plurality of optical members are arranged rotationally symmetrically with respect to the optical axis of the objective lens. The microscope apparatus according to claim 4,
The microscope device, wherein the plurality of light source units are arranged rotationally symmetrically with respect to the optical axis of the objective lens. The microscope apparatus according to claim 5,
The microscope apparatus, wherein an area of an incident end face of the illumination light of each of the plurality of optical members is larger than any area of the plurality of light source units. The microscope apparatus according to claim 6, wherein
Each of the plurality of light source units is arranged in a rotationally symmetrical manner with respect to a central axis of a cross-sectional shape of any one of the plurality of optical members. The microscope apparatus according to any one of claims 2 to 7,
2. The microscope apparatus according to claim 1, wherein an incident end face of the plurality of illumination lights in each of the plurality of optical members is formed of any one of a flat surface, a spherical surface, and a conic surface. The microscope apparatus according to any one of claims 2 to 8,
Each of the plurality of optical members is formed of a single plastic material. The microscope apparatus according to any one of claims 2 to 9,
Each of the plurality of optical members is formed of an optical fiber. A plurality of light source units for emitting illumination light for dark field observation;
A light guide part that guides the illumination light emitted from the light source part through a plurality of optical members, which are parallel to each other and are arranged in contact with each other without an air layer;
A dark field illumination device comprising: a deflection unit made of a single member that deflects the illumination light guided by the light guide unit.