JP2009058953A - Microscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily adjust a diaphragm. <P>SOLUTION: The microscope 51 includes: an illumination optical system which introduces a light flux from an illumination light source stored in an accommodation part 81 and illuminates a sample 90; and an ocular optical system which introduces the light reflected by the sample 90 to an eyepiece 76 so that the observer can observe the image of the sample 90 through an objective lens. Provided that a direction parallel to the optical path P17 of the eyepiece 76 when viewed from above is regarded as a vertical direction, an optical path P12 which introduces the light flux emitted from a light source in a horizontal direction by means of a mirror 114 is formed in at least a part of the illumination optical system, and a diaphragm member for controlling the light flux from the light source is arranged in the light path P12 formed in the horizontal direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a microscope, and more particularly to a microscope in which an aperture can be easily adjusted.

  In the microscope, an illumination light source is provided, and illumination light from the light source is guided to the illumination optical system to illuminate the sample via the objective lens. The light from the sample is collected by the objective lens and guided to the eyepiece through the observation optical system. A user can observe an image of a sample through an eyepiece (for example, Patent Document 1).

  A stop is arranged in the middle of the illumination optical system, and the user adjusts the stop to adjust the illumination state so that the sample is appropriately illuminated.

JP 2005-234279 A

  By the way, when the light source generates illumination light, heat is also generated. When this heat acts on the sample, the sample may change. Therefore, the light source for illumination is arranged at a position farthest from the microscope main body, particularly the stage on which the sample is placed.

  In the conventional microscope, the light path from which the illumination light from the illumination light source is directed to the objective lens is arranged in the depth direction (that is, the front-rear direction) when the microscope is viewed from above. As a result, the position of the stop arranged in the middle of the illumination optical system (position when the microscope is viewed from above) is a position far from the user.

  For example, an optical path length of 40 to 50 mm for the collector lens disposed immediately after the illumination light source, 100 to 250 mm for the subsequent relay optical system, and 80 to 120 mm for the subsequent field lens group is required. Become. When the optical path having the length up to this point is horizontally arranged and the subsequent optical path is vertically deflected and guided to the objective lens, the length of the horizontal optical path is about 220 mm to 420 mm. Actually, in addition to that, an optical path of observation light is further required.

  In this way, when the optical path of the illumination optical system when viewed from above is arranged in the depth direction, the position of the member for adjusting the diaphragm becomes far from the user, and the user can observe the sample through the eyepiece while observing the sample. The operability when adjusting is not always good.

  The present invention has been made in view of such circumstances, and makes it possible to easily adjust the aperture.

The present invention provides an illumination optical system for guiding a light beam from a light source for illumination and illuminating a sample;
In a microscope having an observation optical system for guiding light from the sample to the eyepiece so that the image of the sample can be observed through the objective lens, the optical path of the eyepiece when the microscope is viewed from above When the direction parallel to the vertical direction is the vertical direction, the illumination optical system has an optical path for guiding the light beam from the light source in the horizontal direction at least in part, and the light source in the horizontal optical path It is a microscope with which the aperture member which squeezes the light beam from is arranged.

  In the present invention, when the vertical direction is the direction parallel to the optical path of the eyepiece when the microscope is viewed from above, the illumination optical system guides the light beam from the light source to at least a part thereof in the lateral direction. The diaphragm of the illumination optical system is disposed in the lateral optical path.

  As described above, according to the present invention, since the stop of the illumination optical system is arranged in the optical path that guides the light beam from the light source in the lateral direction, the stop can be easily adjusted.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 to 3 show the configuration of an embodiment of a microscope to which the present invention is applied. A revolver 62 is rotatably disposed above the right side of the main body 61 of the microscope 51. Several objective lenses are detachably attached to the revolver 62, and the user rotates the revolver 62 as necessary, and a desired objective lens among the attached objective lenses is predetermined. The objective lens to be used can be selected by arranging at the position. FIG. 1 shows a state where only one objective lens 120 is attached.

  Above the revolver 62, a fixing plate 63 is attached horizontally to the main body 61. The stages 64 and 65 are movably arranged with respect to the fixed plate 63 along the X-axis direction (left-right direction in FIG. 2) and the Y-axis direction (up-down direction in FIG. 2), respectively. An adjustment member 69 and an adjustment member 70 are rotatably attached to an adjustment shaft 68 arranged to extend downward on the right side of the revolver 62. When the user rotates the adjustment member 69 or the adjustment member 70 clockwise or counterclockwise, the stage 64 or the stage 65 is moved along the X-axis direction or the Y-axis direction, respectively.

  A sample holder 66 is detachably disposed on the stage 64. The user selects a predetermined one from the plurality of sample holders 66 according to the sample 90 to be observed, mounts it on the stage 64, and places the sample 90 thereon. A hole 67 is formed in the center of the sample holder 66, and the sample 90 is irradiated with the light beam from the objective lens 120 through the hole 67. Therefore, the user can observe a predetermined position in the horizontal plane (in the xy plane) of the sample 90 arranged on the stage 64 by rotating and adjusting the adjustment member 69 and the adjustment member 70.

  A focusing handle 71 is attached to the right side of the main body 61, and a focusing handle 71 'and a focusing handle 72 are rotatably attached to the left side. The user adjusts the focusing handle 71 or the focusing handle 71 ′ to rotate, so that the revolver 62 on which the objective lens 120 is mounted is moved close to or away from the sample 90. Can be finely adjusted, and by rotating and adjusting the focusing handle 72, the revolver 62 is moved closer to or away from the sample 90 by coarse movement, so that the focus can be coarsely adjusted and finely adjusted.

  An adjustment member 75 comprising an adjustment member 73 for adjusting the aperture stop and an adjustment member 74 for adjusting the field stop is rotatably attached to the front surface of the main body 61 and obliquely to the lower right of the eyepiece 76. The user adjusts the degree of opening of the diaphragm member 117 (the aperture diaphragm 115 or the field diaphragm 116), which will be described later, by rotating and adjusting the adjustment member 75 (the aperture diaphragm adjusting member 73 or the field diaphragm adjusting member 74). Can be adjusted.

  An eyepiece 76 is disposed on the upper left front side of the main body 61. The eyepiece 76 is disposed above the stage 64. The user can observe an image of the sample 90 through the eyepiece 76. Further, if the line of sight is removed from the eyepiece lens 76, the sample 90 can be confirmed with the naked eye. The eyepiece 76 may be an eyepiece optical system including one or a plurality of lenses.

  On the rear side of the left side surface of the main body 61, there is provided an operation section 91 that is operated when an optical member such as a filter 151 or a polarizing element, which will be described later with reference to FIG. Yes.

  An accommodation portion 81 is disposed on the rear left side of the back surface of the main body 61. A light source 111 for illumination, which will be described later with reference to FIG. A heat radiating fin 81 </ b> A for releasing heat generated by the light source 111 is formed on the side surface of the housing portion 81. The accommodating portion 81 is provided from the mounting position of the sample holder 66 on the stage 64 and the eyepiece 76 so that the heat generated from the light source 111 does not affect the sample 90 and does not cause discomfort to the user looking into the eyepiece 76. It is arrange | positioned in the position where the distance of becomes long.

  FIG. 4 shows the configuration of the optical system inside the main body 61. This optical system guides the light beam from the illumination light source 111 and illuminates the sample 90 via the objective lens 120, and the sample so that the sample image can be observed via the objective lens 120. The observation optical system 102 guides the reflected light from the eyepiece lens 76.

  In the illumination optical system 101, a light source 111 such as a halogen lamp emits an illumination light beam. The illumination light beam travels in the order of the collector lens 112, the relay optical system 113, and the mirror 114 arranged in the direction of the optical path P11. The light source 111 is disposed in the vicinity of the front focal plane of the collector lens 112, and the collector lens 112 converts divergent light from the light source 111 into substantially parallel light. The relay optical system 113 forms a light source image that is an image of the light source 111 at the position of the aperture stop 115. The mirror 114 is disposed between the light source image and the relay optical system 113, and the light beam traveling on the optical path P11 from the light source 111 toward the direction of the user (in the direction of the eyepiece 76 when viewed from above) is directed rightward. The light is deflected to be a light beam in the optical path P12. That is, in FIG. 2 when the microscope is viewed from the upper surface, when the vertical direction is a direction parallel to the nearest optical path P11 of the light source 111 directed downward in parallel with the paper surface, the optical path is deflected to a lateral optical path P12. Is done.

  In the optical path P12, an aperture stop 115, a field stop 116, a field lens group 118, and a half mirror 119 are sequentially arranged. The aperture stop 115 is disposed at a position in the optical path P12 where an image of the light source 111 is formed by the collector lens 112 and the relay optical system 113. The field stop 116 has a substantially conjugate relationship with the rear focal plane of the collector lens 112 in the optical path P12, and is arranged in the vicinity of the position where the image of the rear focal plane of the collector lens 112 is formed by the relay optical system 113. The The field lens group 118 is arranged so that its front focal plane overlaps the field stop 116 in order to project the image of the field stop 116 onto the observation surface of the sample 90.

  The half mirror 119 as a light beam combining member deflects the optical path P12 of the light beam for illumination from the field lens group 118 in the vertical direction (upward in FIG. 1), and sets it as an optical path P13 toward the objective lens 120. This optical path P13 is an optical path centered on the optical axis of the objective lens 120, and the optical axis of the optical path P13 for illumination coincides with the optical axis of the optical path P14 for observation by the objective lens 120 by the half mirror 119. . The light beam deflected in the optical path P13 forms an image of the light source 111 at the position of the pupil of the objective lens 120, becomes substantially parallel light by the objective lens 120, and illuminates the sample 90 made of, for example, metal.

  In the observation optical system 102, the light reflected or scattered by the sample 90 is collected by the objective lens 120 so as to be an observation light beam, and the light beam from each point of the sample 90 is converted into a parallel light beam by the objective lens 120. Thus, the light flux is in the optical path P14 closest to the objective lens 120 that is directed vertically downward from the mounting surface of the sample 90. This light beam is separated from the illumination light beam by passing through the half mirror 119. That is, the half mirror 119 and the objective lens 120 have the functions of both the illumination optical system 101 and the observation optical system 102, and the optical path P13 is a common optical path for the illumination optical system 101 and the observation optical system 102. . The second objective lens 131 disposed in the optical path P14 focuses the light beam transmitted through the half mirror 119, and forms an image 90I of the sample 90.

  The mirror 132 deflects the substantially vertical optical path P14 substantially horizontally and in the left direction in FIGS. 1 and 4 to form an optical path P15. Accordingly, the optical path P15 is substantially parallel to the optical path P12, and as shown in FIG. 2, the optical path is located on the same single straight line when viewed from above.

  In the optical path P15, a primary image that is an intermediate image of the sample 90 formed by the second objective lens 131 is formed. The light beam forming the intermediate image is incident on the mirror 134 via the relay lens 133, is deflected almost vertically upward by the mirror 134, and travels to the optical path P16. The relay lens 133 and the relay lens 135 relay the imaging light to guide the primary image to the optical axis of the eyepiece lens 76. The light beam from the mirror 134 is relayed by the relay lens 135 disposed in the optical path P16 constituting the relay optical system together with the relay lens 133 disposed in the optical path P15, and is incident on the imaging lens 136 in the optical path P16. The light beam emitted from the imaging lens 136 is reflected by the prism 137, divided into two optical paths by an optical path splitting optical element (not shown), and enters the eyepiece lens 76 along the optical path P17. Therefore, the user can observe an enlarged image of the sample 90 through the eyepiece 76 with the eye 140.

  FIG. 5 shows the relationship between the optical paths of the illumination optical system 101 and the observation optical system 102 as viewed from above. An optical path P11 for illumination and an optical path P17 of the eyepiece 76 are optical paths substantially parallel to the depth direction of the microscope 51 (the vertical direction in FIG. 2 and the horizontal direction in FIG. 3). 140). Therefore, the light source 111 has an arrangement configuration that can be arranged at a position sufficiently away from the observer. Further, the optical path P12 and the optical path P15 are optical paths that are substantially perpendicular to the optical path P11, and hence the optical path P17. Therefore, since the stage is arranged in the left and right direction with respect to the user, it is easy to reach the sample 90 arranged on the stage while looking through the eyepiece lens 76.

  When the eyepiece 76 can rotate in the optical axis direction with respect to the optical path P16, at least the optical path P17 is a microscope with respect to the optical path P12 of the illumination optical system 101 or the optical path P15 of the observation optical system 102. The thing which can be made into the state which has a vertical-horizontal relationship seeing 51 from the upper surface corresponds to this invention. In addition, the microscope 51 can perform epi-illumination with the optical path P13 closest to the sample side of the illumination optical system 101 and the observation optical system 102 as a common optical path. Therefore, it is optimal for an inverted microscope in which a heavy sample can be easily placed on the stage, and the hand can easily reach the sample during microscopic observation.

  FIG. 6 shows the details of the positional relationship of the optical members arranged in the optical path of the illumination optical system 101. The light source 111 and the aperture stop 115 are conjugate, and the back focal plane of the objective lens 120 in FIG. 4 is substantially conjugate. The focal plane F112 of the collector lens 112 where the light emitted from the light source 111 parallel to the optical axis is focused by the collector lens 112 and the field stop 116 are conjugate. Further, since the light beam passing through the focal plane F112 and the center of the field stop 116 is converted into parallel light by the field lens group 118, it is conjugated with the observation surface of the sample 90 by the objective lens 120.

  Thus, in the present embodiment, the direction of the optical path P11 parallel to the optical path P17 of the eyepiece lens (vertical direction in FIG. 6), that is, the direction in which the user faces when the user uses the microscope 51, is the vertical direction. At this time, the light beam from the light source 111 is deflected in the horizontal direction, that is, in the left-right direction as viewed from the user, by the mirror 114 as the deflecting member. An aperture member 117 as an aperture member composed of the aperture stop 115 and the field stop 116 is disposed in the horizontal optical path P12. An adjustment member 75 that adjusts the diaphragm member 117 with a known structure is disposed in the vicinity of the diaphragm member 117. Accordingly, the adjusting member 75 (the adjusting member 73 for adjusting the aperture stop and the adjusting member 74 for adjusting the field stop) for adjusting the diaphragm member 117 is attached to the front surface of the main body 61 (that is, the four sides of the substantially rectangular parallelepiped main body 61). Among them, it can be arranged on the surface closest to the eyepiece lens 76, and the user can easily operate the adjusting member while working with the eye 140 close to the eyepiece lens 76.

  Further, since the optical path P12 is arranged in the horizontal direction, the length in the depth direction is shorter than in the case where the optical path P12 is arranged in the vertical direction on the same straight line as the optical path P11 closest to the light source 111. The position of the operation unit 91 can be arranged close to the eyepiece lens 76. Therefore, the user can easily perform operations such as filter replacement.

  When viewed from above, the angle between the optical path P17 closest to the eyepiece 76 (the optical path P11 closest to the light source 111 parallel to the optical path P17) and the optical path P12, that is, the direction of the optical path P17 closest to the eyepiece 76 is the vertical direction. In this case, the angle in the horizontal direction does not necessarily have to be exactly vertical as long as the adjustment member 75 for adjusting the aperture stop 115 and the field stop 116 can be disposed in front of the main body 61. The angle may be slightly obtuse or acute.

  As shown in FIG. 7, in the illumination optical system 101, the mirror 114 is omitted, and the optical path P11 composed of the light source 111, the collector lens 112, and the relay optical system 113 is made parallel to the optical path P12, that is, the illumination optical system. The optical path of the system 101 may be a single straight line, and the whole may be arranged in the horizontal direction (left-right direction) with respect to the vertical direction of the optical path P17 of the eyepiece 76. However, when the optical path of the illumination optical system 101 is made to be a single straight line, the accommodating portion 81 of the light source 111 is closer to the observer. For this reason, it is likely that the storage unit 81 will be touched accidentally and the user will be uncomfortable, so it is preferable to change the directions of the optical path P11 and the optical path P12 as in the present embodiment.

In order to arrange both the aperture stop 115 and the field stop 116 on the optical path P12, it is necessary to bring the field stop 116 close to the optical path P13 of the objective lens 120. For this purpose, the present inventor determines the focal length f1 of the field lens group 118 and the distance L1 along the optical axis between the surface of the field lens group 118 farthest from the field stop 116 and the surface of the field stop 116. The relationship of the formula (1) is satisfied.
1 <L1 / f1 <1.2 (1)

  If the value of L1 / f1 is smaller than the lower limit value, that is, 1 or less, a strong telephoto ratio is applied to the field lens group 118, and aberrations, particularly field curvature, cannot be corrected. Specifically, the field curvature can be evaluated by Petzval sum, but if this value exceeds ± 0.015 as a guideline, when observing a flat sample, the focus is different between the center and the edge. It becomes possible to recognize visually. When the value of L1 / f1 is smaller than the lower limit value, it becomes difficult to suppress the Petzval sum value within a range of ± 0.015. When parallel light is incident on the field lens group 118 from the direction of the half mirror 119 in the direction opposite to the direction in which the illumination light travels, ray tracing is performed on the surface of the field stop 116. In this case, if the Petzval sum value is large, field curvature occurs. Therefore, when the image of the field stop 116 is superimposed on the surface of the sample 90 during observation, the in-focus surface is shifted due to the aperture diameter of the field stop 116. Phenomenon happens and operability deteriorates.

  On the other hand, when the value of L1 / f1 is larger than the upper limit value, that is, 1.2 or more, the optical path length between the field stop 116 and the field lens group 118 becomes long, which is disadvantageous for miniaturization. As a result, it is necessary to change the arrangement of each part of the entire microscope, or it becomes difficult to arrange both the aperture stop 115 and the field stop 116 on the optical path P12, and the operation unit 91 becomes far from the observer, so that the operability is improved. Gets worse. Therefore, it is preferable that the value of L1 / f1 satisfies the relationship of the formula (1).

Furthermore, in order to arrange the optical path P12 in the horizontal direction with respect to the optical path P11 arranged in the vertical direction (depth direction), it is necessary to arrange a mirror 114 as a deflection member between the relay optical system 113 and the aperture stop 115. is there. For this purpose, the inventor sets the focal length f2 of the relay optical system 113 and the distance L2 along the optical axis from the surface of the optical member closest to the aperture stop 115 of the relay optical system 113 to the surface of the aperture stop 115. It was found that the relationship of the following formula (2) should be satisfied.
0.70 <L2 / f2 <1.0 (2)

  Since the aperture stop 115 is disposed at the position of the rear focal point of the relay optical system 113, in order to dispose the mirror 114 between the relay optical system 113 and the aperture stop 115, the relay optical system 113 closest to the aperture stop 115 is disposed. The distance between the surface and the focal plane, that is, the back focus needs to be sufficiently long. When the value of L2 / f2 exceeds the lower limit value, that is, 0.70 or less, the space for inserting the mirror 114 becomes narrower. For this reason, it is necessary to reduce the effective diameter of the mirror 114, and as a result, the NA of illumination is reduced. On the other hand, when the value of L2 / f2 exceeds the upper limit value, that is, 1.0 or more, the diameter of the light beam for satisfying the necessary illumination NA becomes too large, and the aperture of the relay optical system 113 becomes large. End up. Therefore, it is preferable that the value of L2 / f2 satisfies the relationship of the formula (2).

  FIG. 8 shows that L1 = 54.7 mm and f1 = 50 mm in equation (1), and therefore L1 / f1 = 1.09, L2 = 56.4 mm and f2 = 67.7 mm in equation (2), and therefore L2 / The configuration of the illumination optical system 101 when f2 = 0.83 is shown. In this case, the Petzval sum is 0.014. In FIG. 8, a filter 151 is disposed between the collector lens 112 and the relay optical system 113, and a diffusion plate 152 that diffuses light is disposed immediately before the aperture stop 115. The distance L2 is the sum of the distance L21 along the surface of the relay optical system 113 closest to the mirror 114 and the optical path of the mirror 114, and the distance L22 along the optical axis of the mirror 114 and the aperture stop 115.

  FIG. 9 is a diagram for explaining ray tracing performed by entering parallel light from the direction of the half mirror 119 on the field lens group 118 of FIG. 8 in the direction opposite to the direction in which the illumination light travels. Of the two lenses constituting the field lens group 118, the lens far from the field stop 116 having the surface s16 has a surface s11 far from the field stop 116 and a surface s12 closer. The lens closer to the field stop 116 has a surface s13 far from the field stop 116, an intermediate surface s14, and a near surface s15.

  Table 1 shows the result of ray tracing of the field lens group 118 of FIG. The curvature radii of the surfaces s11 to s16 are 60.000 mm, −60.000 mm, 35.000 mm, −40.000 mm, 75.521 mm, and 0.000 mm, respectively.

  The distance between the surface s11 and the adjacent surface s12 is 6 mm, the distance between the surface s12 and the adjacent surface s13 is 0.5 mm, the distance between the surface s13 and the adjacent surface s14 is 7.5 mm, and the surface s15 adjacent to the surface s14. The distance between the surface s15 and the adjacent surface s16 is 39.2 mm.

  The refractive index nd of d-line (bright line when Na lamp is used as the light source) is 1.49782 for the surface s11 and s13 and 1.65412 for the surface s14. The Abbe number νd is 82.52 for the surfaces s11 and s13, and 39.7 for the surface s14.

  Table 2 shows lens data of the relay optical system 113 in FIG. A surface number is assigned from the surface close to the aperture stop 115 toward the light source 111. Of the two lenses constituting the relay optical system 113, the lens far from the aperture stop 115 has a surface s45 far from the aperture stop 115, an intermediate surface s44, and a near surface s43. The lens close to the aperture stop 115 has a surface s42 far from the aperture stop 115 and a close surface s41.

  Table 2 shows the result of ray tracing of the relay optical system 113 in FIG. Both the radius of curvature and the surface spacing are in millimeters. Further, nd represents the refractive index at the wavelength of the d-line, and νd represents the Abbe number when the d-line is the center wavelength. Further, the distance L21 along the optical path center of the mirror 114 and the surface closest to the mirror 114 of the relay optical system 113 is 26.4 mm, and the distance L22 along the optical path center between the mirror 114 and the aperture stop 115 is 30.0 mm. there were.

  FIG. 10 shows that L1 = 57.9 mm and f1 = 50 mm in equation (1), and therefore L1 / f1 = 1.16, L2 = 54.7 mm and f2 = 69.7 mm in equation (2), and therefore L2 / The configuration of the illumination optical system 101 when f2 = 0.78 is shown. In this case, the Petzval sum is 0.009.

  FIG. 11 is a diagram for explaining ray tracing performed on the field lens group 118 of FIG. Of the two lenses constituting the field lens group 118, the lens far from the field stop 116 having the surface s27 has a surface s21 far from the field stop 116, an intermediate surface s22, and a near surface s23. Yes. The lens close to the field stop 116 has a surface s24 far from the field stop 116, an intermediate surface s25, and a near surface s26.

  Table 3 shows the result of ray tracing of the field lens group 118 of FIG. The curvature radii of the surfaces s21 to s27 are 34.800 mm, −32.300 mm, −64.922 mm, 23.120 mm, −33.500 mm, 26.450 mm, and 0.000 mm, respectively.

  The distance between the surface s21 and the adjacent surface s22 is 10 mm, the distance between the surface s22 and the adjacent surface s23 is 5.0 mm, the distance between the surface s23 and the adjacent surface s24 is 7.7 mm, and the surface s25 adjacent to the surface s24. The distance between the surface s25 and the adjacent surface s26 is 5 mm, and the distance between the surface s26 and the adjacent surface s27 is 18.2 mm.

  The refractive index nd of the d line is 1.49782 for the surfaces s21 and s24, 1.65412 for the surface s22, and 1.7725 for the surface s25. The Abbe number νd is 82.52 for the surfaces s21 and s24, 39.7 for the surface s22, and 49.61 for the surface s25.

  Table 4 shows lens data of the relay optical system 113 shown in FIG. A surface number is assigned from the surface close to the aperture stop 115 toward the light source 111. Of the four lenses constituting the relay optical system 113, the lens farthest from the aperture stop 115 has a surface s58 far from the aperture stop 115 and a near surface s57. Next, the lens far from the aperture stop 115 has a surface s56 far from the aperture stop 115 and a near surface s55. Next, the second closest lens from the aperture stop 115 has a surface s54 far from the aperture stop 115 and a close surface s53. The lens closest to the aperture stop 115 has a surface s52 far from the aperture stop 115 and a close surface s51.

  Table 4 shows the result of ray tracing of the relay optical system 113 in FIG. Both the radius of curvature and the surface spacing are in millimeters. Further, nd represents the refractive index at the wavelength of the d-line, and νd represents the Abbe number when the d-line is the center wavelength.

  The distance L21 along the surface of the relay optical system 113 closest to the mirror 114 and the optical path center of the mirror 114 is 25.0 mm, and the distance L22 along the optical path center between the mirror 114 and the aperture stop 115 is 29.7 mm. there were.

  As shown in FIG. 12, the relay optical system 113 in FIG. 10 is divided into a front optical system 113A and a rear optical system 113B, and a mirror 114 is provided between the front optical system 113A and the rear optical system 113B. It can also be arranged. However, the configuration configured as shown in FIG. 10 can bring the sample 90 and the eyepiece 76 closer to each other, and the whole can be made compact.

  FIG. 13 shows L1 = 65.8 mm and f1 = 60 mm in equation (1), and therefore L1 / f1 = 1.10, L2 = 50.0 mm in equation (2), f2 = 67.7 mm, and therefore L2 / The configuration of the illumination optical system 101 when f2 = 0.74 is shown. In this case, the Petzval sum is 0.012. In FIG. 13, as in the case of FIG. 8, a filter 151 is disposed between the collector lens 112 and the relay optical system 113, and a diffusion plate 152 that diffuses light is provided immediately before the aperture stop 115. Has been placed.

  FIG. 14 is a diagram for explaining ray tracing performed on the field lens group 118 of FIG. Of the two lenses constituting the field lens group 118, the lens far from the field stop 116 having the surface s36 has a surface s32 closer to the field s31 farther from the field stop 116. The lens close to the field stop 116 has a surface s33 far from the field stop 116, an intermediate surface s34, and a near surface s35.

  Table 5 shows the result of ray tracing of the field lens group 118 of FIG. The curvature radii of the surfaces s31 to s36 are 71.000 mm, −71.000 mm, 59.000 mm, −41.500 mm, 263.308 mm, and 0.000 mm, respectively.

  The distance between the surface s31 and the adjacent surface s32 is 6 mm, the distance between the surface s32 and the adjacent surface s33 is 0.5 mm, the distance between the surface s33 and the adjacent surface s34 is 7.5 mm, and the surface s35 adjacent to the surface s34. The distance between the surface s35 and the adjacent surface s36 is 50.3 mm.

  The refractive index nd of the d-line is 1.49782 for the surfaces s31 and s33 and 1.654115 for the surface s34. The Abbe number νd is 82.52 for the surfaces s31 and s33, and 39.7 for the surface s34.

  Table 6 shows lens data of the relay optical system 113 shown in FIG. A surface number is assigned from the surface close to the aperture stop 115 toward the light source 111. Of the two lenses constituting the relay optical system 113, the lens far from the aperture stop 115 has a surface s65 far from the aperture stop 115, an intermediate surface s64, and a near surface s63. The lens close to the aperture stop 115 has a surface s62 far from the aperture stop 115 and a close surface s61.

  Table 6 shows the result of ray tracing of the relay optical system 113 in FIG. Both the radius of curvature and the surface spacing are in millimeters. Further, nd represents the refractive index at the wavelength of the d-line, and νd represents the Abbe number when the d-line is the center wavelength.

  The distance L21 along the optical path center of the mirror 114 and the surface closest to the mirror 114 of the relay optical system 113 is 20.0 mm, and the distance L22 along the optical path center between the mirror 114 and the aperture stop 115 is 30.0 mm. there were.

  The configuration of FIG. 13 can make the distance between the relay optical system 113 and the mirror 114 shorter than the configurations of FIGS. 8 and 10. To shorten the distance between the relay optical system 113 and the mirror 114 means to reduce the value of L2 / f2 in the equation (2). When the relay optical system 113 is brought close to the mirror 114, the diameter of the converged light emitted from the relay optical system 113 and directed to the aperture stop 115 can be reduced. Therefore, the diameter of the relay optical system 113 and the diameter of the mirror 114 are reduced. be able to.

  However, if the diameter is made too small and the lower limit value of the expression (2) is exceeded, the relay optical system 113 and the mirror 114 will come into contact with each other. As described above, the NA of the illumination cannot be reduced.

  The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

It is a front view which shows the structure of one Embodiment of the microscope of this invention. It is a top view which shows the structure of one Embodiment of the microscope of this invention. It is a side view which shows the structure of one Embodiment of the microscope of this invention. It is a perspective view which shows the structure of the optical system for illumination of one Embodiment of the microscope of this invention, and the optical system for observation. It is a top view which shows the structure of the optical system for illumination of one Embodiment of the microscope of this invention, and the optical system for observation. It is a top view which shows the structure of the optical system for illumination of one Embodiment of the microscope of this invention. It is a top view which shows the structure of the optical system for illumination of one Embodiment of the microscope of this invention. It is a top view which shows the structure of the optical system for illumination of one Embodiment of the microscope of this invention. It is a top view which shows the structure of the field lens group for ray tracing, and a field stop. It is a top view which shows the structure of the optical system for illumination of one Embodiment of the microscope of this invention. It is a top view which shows the structure of the field lens group for ray tracing, and a field stop. It is a top view which shows the structure of the optical system for illumination of one Embodiment of the microscope of this invention. It is a top view which shows the structure of the optical system for illumination of one Embodiment of the microscope of this invention. It is a top view which shows the structure of the field lens group for ray tracing, and a field stop.

Explanation of symbols

  51 microscope, 61 main body, 64, 65 stage, 71, 72 focusing handle, 73, 74 adjustment member, 76 eyepiece, 81 container, 90 sample, 120 objective lens, 111 light source, 112 collector lens, 113 relay optical system , 114 mirror, 115 aperture stop, 116 field stop, 117 stop member, 118 field lens group, 119 half mirror

Claims (6)

An illumination optical system that guides the light beam from the illumination light source and illuminates the sample;
In a microscope having an observation optical system for guiding light from the sample to an eyepiece so that an image of the sample can be observed through an objective lens,
When the vertical direction is the direction parallel to the optical path of the eyepiece when the microscope is viewed from above, the optical system for illumination guides the light beam from the light source to the lateral direction at least in part. And a diaphragm member that restricts the light beam from the light source is disposed in the lateral optical path. When the microscope is viewed from above, the optical path of the illumination optical system closest to the light source is substantially parallel to the optical path of the eyepiece,
The microscope according to claim 1, wherein the illumination optical system includes a deflection member that deflects a light beam from the light source toward the lateral optical path. The illumination optical system has a relay optical system that collects a light beam from the light source to form a light source image,
The deflection member deflects the light beam from the relay optical system toward the diaphragm member.
The microscope according to claim 2. The diaphragm member includes a field diaphragm,
The illumination optical system is a field lens disposed closer to the objective lens than the field stop so that a front focal plane overlaps the surface of the field stop in order to project an image of the field stop onto a sample surface. Have a group,
When the focal length of the field lens group is f1, and the distance along the optical axis between the surface of the field lens group farthest from the field stop and the surface of the field stop is L1, the focal length f1 and the distance L1 are The following formula 1 <L1 / f1 <1.2
The microscope according to claim 2 or 3, wherein: The diaphragm member includes an aperture diaphragm disposed on the sample side of the relay optical system,
When the focal length of the relay optical system is f2, and the distance along the optical axis from the surface of the optical member closest to the aperture stop of the relay optical system to the aperture stop surface is L2, the focal length f2 and the distance L2 is expressed by the following formula: 0.7 <L2 / f2 <1.0
The microscope according to claim 3 or 4, wherein: A light beam combining member having a light path on the sample side of the illumination optical system and the observation optical system as a common light path, and an objective lens is disposed closer to the sample side than the light beam combining member. Item 6. The microscope according to any one of Items 1 to 5.

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