JP2004318181A - Inverted microscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inverted microscope which allows three or more optical paths to be reserved as photographic optical paths and is useful in research fields such as life science to meet the demand for various researches. <P>SOLUTION: The inverted microscope is provided with; a light source 3 for generating illuminating light; an illumination optical system 4 for irradiating a sample 9 with light generated by the light source 3 to; an objective lens 11 which is arranged in opposition to the sample 9 and on which object light from the sample 9 is made incident; light branching means 16 and 22 which are arranged on an optical path between a primary image formed by the objective lens 11 and the objective lens 11 and branch light passing the objective lens 11 in three or more directions different from one another; an observation optical path 23 on which light branched by light branching means 16 and 22 is made incident; and three or more photographic optical paths 17a, 17b, 17c and 17d on which light branched by light branching means 16 and 22 is made incident. One of photographic optical paths 17a, 17b, 17c and 17d can be branched to a lower optical path of light branching means 16 and 22, and the plurality of photographic optical paths 17a, 17b, 17c and 17d including the lower optical path 17d can be simultaneously used. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a microscope that requires a plurality of optical paths for observing a sample image with an eyepiece and photographing with a still camera and a TV camera, and for observing and photographing an image of a phase object sample such as a cultured cell.

  There is known a microscope in which a steel camera or a TV camera is attached to a mirror body so that an enlarged image of a sample can be photographed by the camera together with visual observation performed through an eyepiece. Japanese Patent Publication No. Hei 4-30565 discloses a microscope provided with an optical element for guiding light of an enlarged image of a sample to a photographing optical path. This microscope includes a first optical element for guiding light from an objective lens to a photographing optical path, and a second optical element for guiding light from the objective lens to an observation optical path. In this microscope, the photographing optical path in two directions can be selected by switching the first optical element in three stages in a direction orthogonal to the optical axis, and in addition to the observation optical path, the photographing optical path of a TV camera, a still camera, or the like. Can be appropriately selected.

  In Japanese Patent Application Laid-Open No. 3-172816, a beam splitter is interposed in the middle of an observation optical path reflected (branched) by a second optical element. There is disclosed a microscope that simultaneously guides light not only to an observation optical path but also to a photographing optical path.

In recent years, in the field of life science research, with the development of high-sensitivity imaging devices and the development of fluorescent reagents, research experiments to detect extremely weak light that cannot be detected by the human eye, such as weak fluorescence observation and weak photometry, have increased. I have. In the observation technique called video microscopy, light from a sample (sample) is modulated, for example, by adding a differential interference effect, and the modulated image is processed (enhanced) into an image separately detected by an imaging device. Thereby, the detection sensitivity of the moving amount and the position of the moving sample is improved.
Japanese Patent Publication No. 4-30565 JP-A-3-172816

  However, the above-mentioned microscope still has the following problems to be solved.

  (1) The number of photographing optical paths is small. In other words, two photographing optical paths are required, of course, by providing a TV camera and a still camera for obtaining a picture, but two or more types of TV cameras cannot be provided and used properly.

  For example, in weak fluorescence observation, there are three types: a cold CCD camera for improving the spatial resolution, a photodiode array for improving the temporal resolution, and a small CCD camera for recording the morphology of the specimen. Since a TV camera needs to be installed, at least three or more photographing optical paths are required.

  In the inverted microscope disclosed in Japanese Patent Publication No. Hei 4-30565, the first optical element is switched in three stages to secure the photographing optical paths in two directions (front side and left side). Is for 35mm still cameras only. Therefore, only one TV camera can be attached.

  (2) The sizes of the images formed on the respective photographing optical paths do not exactly match. That is, when images are captured by a plurality of TV cameras, the size of each obtained image is accurately grasped, and the changes and movements of the sample over time are accurately obtained by superimposing and comparing the images. However, when the sizes of the images do not match, these methods cannot be adopted.

  (3) The loss of light amount is large in each photographing optical path and observation light path, and the amount of light loss in each photographing optical path and each observation light path does not match.

  For example, in a general inverted microscope, the number of times of reflection of light to the observation lens barrel is three, and the loss of light amount and the deterioration of an image due to reflection are remarkable. In particular, in an inverted microscope, it is customary to match the direction of the observation image with the direction viewed from above, and the number of reflections must be an odd number, and the number of reflections in the observation optical path is selected to be 1, 3, 5, etc. It is.

  For example, in Japanese Patent Application Laid-Open No. 3-172816, an observation optical path is guided to an observation lens barrel by one reflection, a beam splitter can be inserted and removed in the middle of the observation optical path, and a TV camera and a photographic device are mounted. A configuration for guiding light to an accessory is disclosed. However, since it is necessary to previously incorporate a prism for correcting the amount of extension of the optical path by the beam splitter in the observation lens barrel, loss of observation light amount and image deterioration are likely to occur.

  The present invention has been made in view of such circumstances, and provides an inverted microscope that can secure three or more optical paths as a photographing optical path and that is useful in research fields such as life science and can respond to various research requests. The purpose is to do.

  An inverted microscope according to the present invention includes a light source that generates illumination light, an illumination optical system that irradiates the sample with the illumination light generated by the light source, and an objective lens that is arranged to face the sample and receives object light from the sample. A light branching unit disposed on an optical path between a primary image formed by the objective lens and the objective lens, and branching light passing through the objective lens in three or more different directions from each other; An observation optical path on which the divided light is incident, and three or more photographing optical paths on which the light branched by the light branching means is incident, and one of the photographing optical paths is provided in a lower optical path of the light branching means. It can be branched, and the lower optical path and another photographing optical path can be used simultaneously.

  Another inverted microscope according to the present invention includes a light source that generates illumination light, an illumination optical system that irradiates the sample with the illumination light generated by the light source, and an object that is arranged to face the sample and receives object light from the sample. A lens, an imaging lens provided on an optical path of the light passing through the objective lens, and forming an image of the light passing through the objective lens at a predetermined position to form a primary image of the sample; A light branching unit that is arranged on an optical path between the first image and the light that has passed through the objective lens and branches in three or more different directions from each other, and an observation in which the light branched by the light branching unit is incident. An optical path, and three or more photographing light paths on which the light branched by the light branching means is incident, and one of the photographing light paths is branchable to an optical path below the light branching means; and Align the lower optical path with the other Characterized in that that can be used for.

  Still another inverted microscope according to the present invention includes a light source that generates illumination light, an illumination optical system that irradiates the sample with the illumination light generated by the light source, and an object light that is arranged to face the sample and enters from the sample. An objective lens, an imaging lens provided on an optical path of light passing through the objective lens, and imaging the light passing through the objective lens at a predetermined position to form a primary image of the sample, and the objective lens A first optical element that is disposed on an optical path between the first optical element and the first image and that branches light that has passed through the objective lens in different directions, on an optical path of the branched light that is branched by the first optical element A second optical element for guiding the branched light incident from the first optical element in a plurality of directions including an observation optical path, and a light branched by the first optical element and the first optical element. Via the second optical element And three or more photographing optical paths on which light is incident. One of the photographing optical paths is branchable to a lower optical path of the second optical element, and the lower optical path and another photographing optical path are connected to each other. It can be used simultaneously.

  ADVANTAGE OF THE INVENTION According to this invention, three or more optical paths can be ensured as a photographing optical path, and the inverted microscope which is useful also in research fields, such as life science, and which can respond to various research requests can be provided.

  Hereinafter, embodiments of the present invention will be described.

  (First Embodiment) FIGS. 1 to 3 show an embodiment in which the present invention is applied to an inverted microscope. FIG. 1 is a perspective view showing the mutual positional relationship of each optical system in the inverted microscope, FIG. 2 is a perspective view of the microscope viewed from the side, and FIG. 3 is a perspective view of the microscope viewed from the front. is there.

  In this inverted microscope, an illumination housing 2 is attached to an upper end of a mirror housing 1, and a light source 3 is housed in the illumination housing 2. The traveling direction of the light 4 output from the light source 3 is changed downward by the reflection mirror 5. The light 4 bent downward passes through the field stop 6 and enters the condenser lens 7. A condenser lens 7 focuses the light 4 on a sample 9 placed on a stage 8. The light that has passed through the sample 9 enters an objective lens 11 supported by a revolver 10 disposed below the stage 8.

  The light passing through the objective lens 11 is incident on a fluorescent tube 12 having a built-in dichroic mirror inclined at 45 degrees with respect to the optical axis. Illumination light enters the fluorescent tube 12 from a light source 14 of an epi-illumination system 13.

  Below the fluorescent tube 12, an imaging lens 15 for imaging light incident from the objective lens 11 at a focal length position is provided. In FIG. 1, reference numerals 29a to 29d indicate positions where the primary image of the sample 9 is formed by the imaging lens 15. The light passing through the imaging lens 15 enters the first optical element 16.

  As shown in FIG. 1, the first optical element 16 includes three semi-transmissive prisms 16a, 16b, and 16c arranged in contact with each other in a direction perpendicular to the optical axis. Each of the semi-transmissive prisms 16a to 16c has a semi-transmissive surface that allows light incident from above to be transmitted downward, and that reflects light orthogonal to the optical axis of the incident light and in directions different from each other by 90 °.

  Specifically, the semi-transmissive prism 16a transmits the light incident from above downward, and guides the incident light toward the first imaging optical path 17a (leftward). The central semi-transmissive prism 16b transmits the light incident from above downward, and guides the incident light toward the second photographing optical path 17b (forward direction). The semi-transmissive prism 16c transmits the light incident from above downward, and guides the incident light toward the third photographing optical path 17c (rightward).

  The three semi-transmissive prisms 16a, 16b, 16c are movably supported by a support 18 shown by a dotted line in the figure. The translucent prisms 16a, 16b and 16c supported by the support base 18 can be moved in three horizontal positions A, B and C by a position adjusting knob 19 whose tip is exposed on the outer wall of the lens housing 1. is there. When the position adjustment knob 19 is stopped at the position A, the transflective prism 16a is arranged on the optical path of the light 4, and the light 4 is guided to the photographing optical path 17a to form an image at the position 29a. When the position adjustment knob 19 is stopped at the position B, the transflective prism 16b is arranged on the optical path, and the light 4 is guided to the photographing optical path 17b to form an image at the position 29b. When the position adjustment knob 19 is stopped at the position C, the transflective prism 16c is arranged on the optical path, and the light 4 is guided to the photographing optical path 17c to form an image at the position 29c. That is, any translucent prism 16a, 16b, 16c can be selectively moved to the optical axis position of the incident light. As a result, the observer can guide the light passing through the imaging lens 15 to any one of the first to third photographing optical paths 17a to 17c.

  Note that the optical characteristics of the translucent prisms 16a to 16c constituting the first optical element 16 and the translucent mirror of the second optical element 22 can be arbitrarily changed. For example, the reflectance can be selected by selecting a film thickness by depositing a ZnS-Ag thin film in a range of 0 to 100%.

  Further, since the required specifications required for the first and second optical elements 16 and 22 vary depending on the experimental purpose of the researcher, the reflectance / transmittance of the transflective prisms 16a to 16c is also 80/20%. , 50/50%, 100/0%, and 0/100%. In the case of simultaneously measuring the fluorescence of two or more wavelengths, a dichroic mirror having a characteristic of reflecting short-wavelength light and transmitting long-wavelength light is used instead of the transflective prisms 16a to 16c. It is possible to arrange a TV camera or a measuring system element on the photographing optical paths 17a and 17b or the photographing optical paths 17c and 17d to perform simultaneous comparative photometry. Further, it is also possible to select a 100% reflection mirror, that is, a total reflection mirror, as the semi-transparent mirror of the second optical element 22.

The image magnification of the primary image of the sample 9 formed on each of the imaging optical paths 17a to 17c is adjusted so as to completely match. That is, since the objective lens 11 itself is an infinity correction objective lens, there is no need to provide an imaging lens for infinity in the finite correction objective lens, and the sample 9 can be focused by moving the revolver 10. Further, since the imaging lens 15 is an imaging lens corresponding to the infinity correction objective lens, and no lens is inserted between the imaging lens 15 and the focal position 29 of each optical path, the image magnification of each optical path is equal. . In the embodiment, the focal length _{f B} is 180mm of the imaging lens 15, the image magnification is set to [1x].

  Light that has passed downward through any one of the transflective prisms 16a to 16c of the first optical element 16 is incident on the second optical element 22. The second optical element 22 is composed of, for example, a semi-transparent mirror, reflects the incident light in the direction of the observation optical path 23, and transmits the incident light as it is to a new lower imaging optical path 17d.

  The second optical element 22 is movably supported by a support base 24, and can be pulled out of the lens housing 1 by operating the insertion / removal lever 25, similarly to the first optical element 16. It is possible. When the second optical element 22 is pulled out of the optical path by the insertion / removal lever 25, the light enters only the photographing optical path 17d without being guided to the observation optical path 23. When the second optical element 22 is inserted into the optical path, it enters both the observation optical path 23 and the imaging optical path 17d.

  As with the first optical element 16, the second optical element 22 can be replaced by a translucent mirror having other optical characteristics as needed by the observer by the insertion / removal mechanism described above. Further, as a modified example, an integrated body of the support base 24 for holding the optical element 22 and the insertion / removal lever 25 from the bottom surface of the lens housing 1 may be attached to the bottom surface so as to be able to make a splash from the optical path. Even with this splash mechanism, it is possible to switch between a case where the incident light is reflected in the direction of the observation optical path 23 and a case where the light is transmitted only to the new lower imaging optical path 17d.

  The light transmitted through the second optical element 22 and introduced into the photographing optical path 17d forms an image at a predetermined position 29 at the same distance as each of the photographing optical paths 17a to 17c of the first optical element 16. Furthermore, the fact that the image magnification of the primary image of the sample 9 formed on the photographing optical path 17d completely matches each image magnification of each of the photographing optical paths 17a to 17c of the first optical element 16 means that This is apparent from the fact that no lens is interposed between the lens 15 and the focal positions 29a to 29d. Since the imaging surface of the TV camera is arranged at the focal position 29d of the imaging optical path 17d, a TV camera mounting mount (not shown) that fits a flange back of a desired TV camera can be attached to the outside of the lens housing 1 in the imaging optical path 17d. It has become. In other words, the imaging lens has a focal length that allows the mount to be mounted outside the lens housing 1. The same applies to the focal lengths 29a and 29c of the imaging optical paths 17a and 17c.

  However, the focal length 29d of the photographing optical path 17d on the side transmitting the first optical element 16 is such that the mount can be attached to the outside of the lens housing 1 even when the first optical element 16 is detached and is in a transparent state. A lens housing 1 is formed in the housing.

  Light reflected by the second optical element 22 and introduced into the observation optical path 23 also forms an image at a predetermined position 29e. At this image forming position, it is possible to insert a mask glass for confirming the photographing area and a scale glass for comparing the size of the image.

  On the other hand, in the imaging optical system 17b where the light reflected in the horizontal direction by the first optical element 16 is incident, a primary image is formed in the focus type photographic lens 30a. This primary image is magnified by the photographic lens 30a and forms a secondary image on the film surface 29, and the image of the sample 9 is recorded on the film surface 29.

  An imaging optical path is provided below the second optical element 22, that is, also on the back side of the microscope, and the projection magnification of the other imaging optical paths is equal to that of the other imaging optical paths, so that more TV cameras can be mounted.

  Since the first optical element 16 and the second optical element 22 can be inserted into and removed from the lens housing 1 and can be easily exchanged, various research experiments and individual requirements of researchers can be achieved. A matching imaging optical path can be configured, a single microscope can cope with the diversification and development of research experiments, and work efficiency can be further improved.

  As described above, according to the present embodiment, since the imaging optical path reflected by the first optical element 16 is provided with three optical paths, one optical path is used as a 35 mm camera optical path for photographing, and the remaining two optical paths are used. It can be used as a combination of a high-sensitivity TV camera and a high-resolution TV camera, and the projection magnification of each imaging optical path is the same. This facilitates comparison work and improves the usability, work efficiency, and experimental accuracy of research realizations such as weak fluorescence observation and photometry. Specifically, part of the observation cells in the field of view are aligned with the center of the cooled CCD, and the photodiode array is further matched with the center of the cooled CCD. May be switched.

  FIG. 4 is a perspective view showing the relationship between the transflective prisms 16a to 16c and the support base 18. The support base 18 has a dovetail groove 18a formed in the horizontal direction, and the dovetail 20a of the moving member 20 which is moved by the position adjustment knob 19 is slidably engaged with the dovetail groove 18a. By the operation of the position adjustment knob 19, the moving member 20 slides in the horizontal direction between the dovetail 20a and the dovetail groove 18a.

  The stopper screw 21 'is screwed in the vicinity of the end of the dovetail groove 18a as shown. By adjusting the amount of protrusion of the head of the stopper screw 21 ', positioning is performed when the transflective prism 16c on the opposite side enters the optical axis position.

  Similarly, a stopper screw is provided on the opposite side of the dovetail groove 18a in the figure. By adjusting the stopper screw, positioning is performed when the semi-transmissive prism 16a located on the near side enters the optical axis position. Although not shown, a known click mechanism is used as a method for positioning the central semi-transmissive prism 16b at the optical axis position.

  The moving member 20 has dovetail grooves 20a ", 20b", 20c "engraved in the vertical direction, and the supporting frames 21a, which support the transflective prisms 16a, 16b, 16c in the dovetail grooves 20a", 20b ", 20c". 21b and 21c are inserted. The direction of the dovetail grooves 20a ", 20b", 20c "is not limited to the vertical direction, and may be the same as the sliding direction of the moving member 20. In this case, there is no problem. 21c are fixed by pressing the tips of the screws 21a 'to 21c' into the dovetail grooves 20a ", 20b", 20c ", respectively.

  Further, as a modified example, there is no problem even if the moving member 20 and the support frame 21 are fixed by using a positioning pin or a groove together with a fastening means such as a screw. By loosening and removing the stopper screw 21 ′ and operating the position adjustment knob 19, it is possible to pull out the entire moving member 20 on which the support frames 21 a to 21 c are mounted to the outside of the lens housing 1.

  FIG. 5 is a cross-sectional view of FIG. 4 cut along the alternate long and short dash line AA and viewed in the direction of the arrow. The observer can easily pull out the semi-transmissive prisms 16a to 16c of the extracted moving member 20 individually for each of the support frames 21a, 21b, 21c, thereby easily obtaining the semi-transmissive prisms 16a having other optical characteristics. ~ 16c can be exchanged. The semi-transmissive prisms 16a to 16c are detached from the moving member 20 by loosening the screws 21a ', 21b', 21c 'fixing the support frames 21a to 21c and pulling them upward.

  The light that has passed through the imaging lens 15 passes through one of the transflective prisms 16a to 16c selected by the position adjustment knob 19 and through holes 35a to 35c formed in each of the support frames 21a to 21c to form one photographing optical path 17a to 17c. An image is formed at the upper predetermined positions 29a to 29b.

  The light guided to the observation optical path 23 passes through a predetermined imaging position 29e, and then travels toward the observation lens barrel 27 via a relay lens system 26 including a plurality of group lenses. The plurality of group lenses have at least two or more groups. The front group includes a pupil relay lens 26c that relays a pupil image of the objective lens 11, and projects the pupil image of the objective lens 11 to a position 26b. A pupil modulator 26b having amplitude modulation such as a phase plate for phase difference or a modulator for modulation contrast is provided at a position 26b conjugate with the pupil image. The pupil modulator 26b is configured to be detachably provided from the outside of the lens housing 1 by a mechanism described later. The rear group 26a of the plurality of group lenses includes an image relay lens that projects a primary image formed at a primary imaging position 29e of the objective lens 11 at infinity. The light emitted from the image relay lens 26a becomes parallel light and enters the imaging lens 27a in the observation lens barrel 27. The imaging lens 27a forms an image of the incident light at a predetermined position 29e 'in the observation lens barrel 27. The observer can observe an enlarged image of the sample 9 formed at the position 29e 'through the eyepiece 27b.

  Here, the operation of the optical system according to the present embodiment will be described. FIG. 6 shows a configuration of an optical system in the inverted microscope shown in FIGS. 1 to 3 except for a transmission illumination optical system. The image of the sample 9 is enlarged by the objective lens 11, and the enlarged light flux passes through the imaging lens 15 and the first optical element 16, enters the reflection mirror 22, and is reflected to the observation optical path 23 (not shown in FIG. Although part of the drawing is shown, the light is transmitted and enters the imaging optical path 17d). The enlarged light flux reflected by the reflection mirror 22 to the observation optical path 23 forms a primary image at a point 29e. This primary image is guided to the pupil relay lens 26c, the pupil modulator 26b, and the first group of image relay lenses 27a, and is formed near the eyepiece 27b by the second group of image relay lenses 27a. This secondary image is observed by the eyepiece 27b as described above.

  Here, between the image relay lenses 26a and 27a of the first group and the second group, a mounting surface (shown by a broken line in the figure) of the observation lens barrel 27 to the lens housing 1 is located. Therefore, the image relay lens 27a of the second group corresponds to the imaging lens 27a in the observation lens barrel 27.

  Explaining the imaging relationship, the objective lens 11 is designed to be infinity, is primary-imaged by the imaging lens 15, and is secondarily formed near the eyepiece 27b by the pupil relay lens 26c and the image relay lens 27a. Form an image. Since the objective lens 11 is designed at infinity, a parallel optical system is provided between the objective lens 11 and the imaging lens 15. For example, when focusing on the sample 9, the objective lens 11 is moved even if the objective lens 11 is moved. The position of the primary image does not change. Therefore, the focusing mechanism may be configured to move the objective lens 11, and a mechanism generally called a revolving up-and-down system in which a plurality of objective lenses 11 are attached and the revolver 10 is moved up and down can be adopted as the focusing mechanism.

  Further, in the present embodiment, the pupil of the objective lens 11 existing near the revolver mounting surface of the objective lens 11 is reflected by the reflecting mirror 22 through the imaging lens 15 and the first optical element 16 and reflected upward by 45 ° to be reflected by the pupil. The light is projected on the modulator 26b. Furthermore, there is a position conjugate with the pupil of the objective lens 11 near the condenser lens 7, and another pupil modulator can be arranged there. Here, the pupil modulator 26b in the relay lens system 26 is defined as a first pupil modulator, and the pupil modulator arranged near the condenser lens 7 is defined as a second pupil modulator 100.

  Actually, since the optimal position of the pupil modulator in the optical axis direction is slightly changed due to errors of each optical component used in the relay system, particularly the refractive index error, the pupil modulator can be fine-tuned in the optical axis direction. It is more desirable. Therefore, in the present embodiment, the pupil modulator is configured to be capable of adjusting the position in the optical axis direction and aligning the center.

  If an optimal pupil modulator 26b for observing living cells or cultured cells cultured in a microwell plate or a plastic Erlenmeyer flask is prepared, the pupil modulator 26b is simply inserted into the relay lens system 26, and an objective lens is formed. Optimum contrast is obtained for each container without replacement.

  According to the optical system including the first and second pupil modulators, the phase plates 82a and 82b are arranged in the first pupil modulator 26b, and the ring slit is arranged in the second pupil modulator. Observation of the phase difference outside the objective lens becomes possible, and the phase difference observation can be easily performed without using an objective lens dedicated to the phase difference.

  The optimum pupil modulator differs depending on the magnification and NA of the objective lens 11, the pupil position, and the sample 9 to be observed. In this embodiment, the type of the pupil modulator can be switched by the pupil modulation slider 81. Therefore, it is possible to easily switch to the optimum pupil modulator according to the type of the objective lens 11 or the type of the sample 9.

  Since a phase difference and a modulation contrast microscope (Hoffman method) can be used, there is an advantage that observation of cells in a plastic culture container is not affected by deterioration of polarization performance due to the container.

  Phase contrast and modulation contrast microscopes (Hoffman method) can be observed using a low-magnification objective lens. However, when Nomarski is used for the low-magnification objective lens, the pupil aberration of the objective lens causes an error around the field of view. Although retardation occurs and unevenness occurs in the field of view, the present invention does not use the Nomarski interference method, and thus has an advantage that the field unevenness does not occur. In addition, image deterioration, which is a problem in the polarization observation method and the Nomarski observation method, does not occur.

  FIGS. 7 and 8 show a mechanical configuration of the first pupil modulator 26b. The first pupil modulator 26b includes a pupil modulation slider 81 near the conjugate position 95 with the objective lens pupil image in the relay lens system 26, and the pupil modulation slider 81 is connected to a not-shown locking mechanism (for example, a click mechanism). It is designed to lock. The pupil modulation slider 81 has a rectangular overall shape, and has three openings in its longitudinal direction. Two types of phase plates 82a and 82b are held in the openings on both sides so as to be compatible with two types of objectives, and the central opening is a hole 83 for the case where no modulation is performed. A phase plate 82a or 82b corresponding to each type of the objective lens 11 is used.

  On the side surface of the pupil modulation slider 81, a V groove 84 for stopping the slider is provided along the longitudinal direction. Each V-groove 84 engages with the locking mechanism when the corresponding phase plate 82a, 82b or hole 83 is disposed on the optical axis. The phase plate 82 a (82 b) is fixed to a cylindrical holding frame 85, and the outer periphery of the holding frame 85 is axially fitted on the inner peripheral surface of the outer frame 86. The holding frame 85 is provided with an operation knob 88 for adjusting the phase film 87 of the phase plate 82a (82b) to a position conjugate with the pupil of the objective lens. The operation knob 88 is screwed to the outer periphery of the holding frame 85 through the guide groove 89 of the outer frame 86. By moving the operation knob 88 in the optical axis direction along the guide groove 89, the phase film 87 can be adjusted to the conjugate position 95. Further, the phase plate 82a (82b) is fixed by pressing a flange 90 formed on the outer periphery of the knob tip of the operation knob 88 against the outer frame 86.

  In the case of phase difference observation, a phase difference opening is provided in the vicinity of the condenser lens 7 in order to modulate illumination. In order to align the center of the phase film 87 with the position of this opening, the pupil modulation slider 81 is provided. A plunger 91 and two adjustment knobs 92 are provided. The three points at the tips of the plunger 91 and the two adjustment knobs 92 abut on the outer periphery of the outer frame 86, and the center of the phase film 87 can be aligned by rotating the adjustment knob 92.

  Although a sharp image can be obtained by phase difference observation, the directionality of the transparent sample is not known. In the Hoffman modulation contrast, the directionality of the sample can be understood, a thick transparent sample can be observed, and the depth of focus can be seen three-dimensionally. The biological sample is contained in a glass or plastic dish, but in the case of the Hoffman type, the contrast is further improved by placing a polarizing plate in the double-pupil modulator in the glass dish, and without using a polarizing plate in the plastic dish. Another advantage is that it can be released from the polarization distortion of the plastic petri dish.

  In the present embodiment, by disposing the first pupil modulator 26b in the lens housing 1, observation of the phase difference outside the objective lens, the Huffman modulation contrast, and the like can be performed without being separated as in the intermediate lens barrel. It becomes possible.

  The modulation contrast image is different from the phase contrast image, and it is necessary to rotate the pupil modulator in order to adjust the directionality of the image contrast. It can be easily removed and the whole unit can be replaced.

  Since the pupil modulator 26b is provided in the lens housing 1 so that it can be inserted and detached and detached, the pupil modulator can be downsized and the operability can be improved. In addition, since the space between the image relay lens 26a of the observation optical path 23 and the imaging lens 27a of the observation lens barrel 27 is a parallel optical system, the observation lens barrel 27 is not directly attached to the lens housing 1, but is directly connected to the lens housing 1 as shown in FIG. As shown in (a), observation lens barrels 34 having different inclination angles can be attached via an optical path deflecting device 33.

  Here, the optical path deflecting prism 33a in the optical path deflecting device 33 is for leveling the observation lens barrel mounting surface, and the prism 34b attached to the distal end of the observation lens barrel 34 has a tilt angle of the observation lens barrel, for example. It is a prism to make 30 degrees. The imaging lens 34a corresponds to the imaging lens 27a, and the eyepiece 34b corresponds to the imaging lens 27b.

  Further, instead of the optical path deflecting prism 33b shown in FIG. 12A, an optical path deflecting prism 33b shown in FIG. 12B may be used. If the optical path deflection prism 33b shown in FIG. 12B is used, the distance from the sample 9 to the eye point of the eyepiece 27b can be shortened.

  Further, it is possible to easily insert a discussion lens barrel, a variable power lens barrel, a photo lens barrel, or the like as an intermediate lens barrel into the parallel optical system. Specifically, since the observation lens barrel 27 can be easily removed from the lens housing 1, the above-described various intermediate lens barrels may be provided between the observation lens barrel 27 and the lens housing 1 as necessary. It is possible to intervene.

  FIG. 9 is a perspective view when the inverted microscope according to the embodiment is combined with a discussion lens barrel 28 as an example of an intermediate lens barrel when viewed from the front. The discussion tube 28 is an observation tube for the sub-observer to observe at the same time as the main observer, and is mounted above the image relay lens 26a in the observation optical path 23. The discussion lens barrel 28 is mainly composed of an optical path splitting prism 28a, a relay lens 28b, and a reflecting prism 28c, as shown in the figure. The sub-observation barrel 27 'has the same structure as the observation barrel 27, and a support leg 31 for stabilizing the device is provided on the sub-observation barrel side.

  In FIG. 9, the discussion barrel 28 is attached via the optical path deflecting device 33. However, the present invention is not limited to this, and there is no problem even if the discussion barrel 28 is directly attached to the microscope main body (the lens housing 1). However, since the mounting surface is inclined, the lens barrel supporting portion of the support leg 31 can be replaced or adapted to support the inclined discussion lens barrel 28.

  A parallel optical system is provided in the middle of the observation optical path, and the lens barrel housing 1 and the observation lens barrel 27 can be separated at that position. Can be inserted or stacked in two stages. As a result, the scope of application of the microscope can be further expanded. Further, since the intermediate lens barrel is inserted into the parallel optical system, it is not necessary to add a special lens to the intermediate lens barrel, and a high-quality image can always be obtained.

  The image relay lens is composed of a first group 26a for projecting the primary image at infinity and a second group 27a for making the image projected at infinity finite. Since the lens barrel is detachable, it is possible to mount a lens barrel dedicated for observation and a lens barrel for photographing, and it is also possible to take a photograph by guiding an image modulated by the pupil modulator to a photographing device.

  The focal length of the imaging lens is not limited to 180 mm but may be about 150 mm to 200 mm as long as the optical characteristics and the entire optical element arrangement can be arranged in a desired number of fields (for example, 20 or more). But it's fine. In addition, the infinity design objective lens has been described, but a finite design objective lens is also applicable. In this case, the imaging position of the finite design objective lens alone may be extended, or an infinity auxiliary lens may be provided at an immovable position by conversion in a revolver where the finite design objective lens is attached, so that the infinity is achieved.

  Since the objective lens 11 designed at infinity is used, the distance between the imaging lens 15 and the objective lens 11 can be set to 50 mm or more, and a dichroic mirror for performing epi-illumination from the fluorescent light projection tube during this interval. And a prism for Nomarski, a polarizing plate for polarization observation, and the like can be inserted, and various observation methods are possible.

  FIG. 13 shows an example in which the objective lens 11a of finite design in FIG. 6 is used for an inverted microscope. In this inverted microscope, a parallel optical system is formed from the sample 9 through the objective lens 11a and the concave lens 11b, and is condensed by the imaging lens 15a to form an image at predetermined positions 29b and 29e in the drawing (similar to FIG. 1). . Although the relay optical system is the same as that of FIG. 6, it is almost the same, although there are some changes corresponding to the objective lens 11a of finite design. In the case of the finite design, since the observation lens barrel does not include the imaging lens, the two-dot broken line in the figure becomes the mounting surface of the observation lens barrel to the lens housing, and the imaging lenses 26a ', 27a' or the integral 26a '. ′, It can be configured without much difference from the design at infinity.

  (Second Embodiment) Next, a second embodiment of the present invention will be described.

  FIG. 10 is a perspective view showing the mutual positional relationship between the optical systems in the erecting microscope of the embodiment, and FIG. 11 is a perspective view of the microscope of the embodiment as viewed from the side. Light 54 emitted from a light source 53 housed in an illumination housing 52 attached to the lower end of a mirror housing 51 is deflected upward by a reflection mirror 55, passes through a field stop 56, and passes through a condenser lens 57. The light is focused on a sample (specimen) 59 placed on the stage 58. The light transmitted through the sample (sample) 59 is incident on an objective lens 61 supported by a revolver 60 disposed above the stage 58. The light of the enlarged image that has passed through the objective lens 61 is incident on a fluorescent cube 62 including an excitation filter 62a, a dichroic mirror 62b, and an absorption filter 62c. Illumination light is incident on the fluorescent cube 62 from a light source 64 of an epi-illumination system such as a mercury lamp or a xenon light source.

  Above the fluorescent cube 62, an imaging lens 65 for imaging light coming from the objective lens 61 at a focal position is provided. The light that has passed through the imaging lens 65 enters the first optical element 66.

  As shown in FIG. 10, the first optical element 66 includes three semi-transmissive prisms 66a, 66b, and 66c arranged in contact with each other in a direction perpendicular to the optical axis. Each of the semi-transmissive prisms 66a to 66c transmits the light incident from below upward, and branches the incident light in a direction orthogonal to the optical axis of the incident light and in directions different from each other by 90 °.

  Specifically, the semi-transmissive prism 66a transmits the light incident from below upward, guides the incident light toward the first photographing optical path 67a (left direction), and the central semi-transmissive prism 66b receives light from below. The transmitted light is transmitted upward, the incident light is guided in the direction of the second photographing optical path 67b (see FIG. 11), and the semi-transmissive prism 66c transmits the light incident from below and transmits the incident light. The third imaging light path 67c is guided in the right direction.

  The three semi-transmissive prisms 66a, 66b, 66c are movably supported by a support 68 shown by a dotted line in the figure. The translucent prisms 66a, 66b, and 66c supported by the support table 68 are collectively moved to horizontal positions (A), (B), and (C) by a position adjustment knob 70 whose tip is exposed on the outer wall of the optical path splitting unit 69. ) Can be moved to three stages. Therefore, by operating the position adjustment knob 70, any transflective prism 66a, 66b, 66c can be selectively moved to the optical axis position of the incident light. As a result, the observer can guide the light that has passed through the imaging lens 65 to any one of the first to third photographing optical paths 67a to 67c.

  When the position adjustment knob 70 is set to A, the transflective prism 66a is arranged in the optical axis, and the light is guided to the photographing optical path 67a to form an image at a predetermined position (71a). Others also move correspondingly to the alphabet of the position adjustment knob 70. The relationship between the semi-transmissive prisms 66a to 66c and the support table 68 is the same as the configuration of FIG. 4 of the first embodiment, in which the semi-transmissive prisms 66a to 66c are mounted and an arbitrary prism is selectively moved into the optical path 72. Then, the moving member (not shown in the second embodiment but the same as the moving member 20 in FIG. 4) can be pulled out of the housing 69 of the optical path splitting unit. Further, similarly to the first embodiment, each of the transflective prisms 66a to 66c is detachable, and can be replaced with a transflective prism having another optical characteristic.

Further, the image magnification of the sample (specimen) 59 formed on each of the photographing optical paths 67a to 67c is adjusted so as to completely match. That is, since the objective lens 61 itself is an object lens for infinity compensation, the finite correction objective lens does not require an infinity exchange lens, and the sample can be focused by covering the stage 58. Numeral 65 denotes an image forming lens corresponding to an objective lens at infinity. Since no lens is provided between the image forming lens 65 and the focal position 71 of each optical path, the image magnification of each optical path is equal. In the present embodiment, the focal length _{f B} is 180mm of the imaging lens 65, the image magnification is set to [1x].

  Light that has passed upward through any one of the semi-transmissive prisms 66a to 66c of the first optical element 66 enters the second optical element 73. In the present embodiment, the housing 74 of the optical path splitting unit having the second optical element 73 is a generally known trinocular tube, and the optical path splitting prism 73 includes an observation optical path 75 for visual observation and a photograph. And a prism that splits the light into an image pickup optical path 76 for TV shooting, and is constituted by three types of prisms having different division ratios.

  Light in the imaging optical path 76 and the observation optical path 75 transmitted / reflected by the second optical element forms an image at a predetermined position X (71d, e) at the same distance as each of the imaging optical paths 67a to 67c of the first optical element 66. . Furthermore, the fact that the image magnification of the image of the sample 59 formed on the two optical paths 75 and 76 completely matches each image magnification of each of the photographing optical paths 67 a to 67 c of the first optical element 66 is that the imaging lens 65. This is apparent from the fact that no lens is interposed between the optical path and the focal position of each optical path.

  Since the imaging plane of the TV camera is arranged at three focal positions (71a, 71c, 71d) in the photographing optical paths 67a, 67c, 76, a desired TV camera is placed in the three optical paths (67a, 67c, 76). TV camera mounting mounts (69c, 74d) that match the flange back are arranged outside the optical path splitting unit 69 and the trinocular tube 74. Note that a mount (not shown) also exists on the imaging optical path 67a side.

  The case where the first optical element 66b is inserted into the optical path 72 will be described in detail with reference to FIG. The light of the enlarged image of the sample 59 that has passed through the above-described objective lens 61 passes through the imaging lens 65, and then the amount of light corresponding to the ratio of the division ratio of the first optical element 66b is reflected on the photographing optical path 67b side or through the three glasses The light is transmitted to the cylinder 74 side. Since the transmission side has already been described, the light path reflected on the photographing light path 67b will be described here.

  On the optical path on the opposite side, a pupil Lee lens group 77 that relays the pupil image of the objective lens as shown in FIG. 11 and an image formed at the focal position 71b by the imaging lens 65 (the sample passing through the objective lens 61 ( A secondary image relay lens group (two-group configuration) 78, 79 for further relaying the primary image of the specimen 59) and a reflection mirror 96 for deflecting the light horizontally deflected by the first optical element 66b upward are arranged. Have been.

  The housing 69 of the above-described optical path splitting unit includes an image forming lens 65, semi-transmissive prisms 66a to 66c, a pupil relay lens 77, one of a group of secondary image relay lenses 78, and an optical element of a reflection mirror 96. The secondary image relay lens group 78 is a group for projecting the primary image at infinity, and 79 has a role as a group for making the image projected at infinity finite. It is a parallel light flux. Reference numeral 95 denotes a position conjugate with the pupil image of the objective lens 61 projected by the pupil relay lens 77.

  The housing 69 of the optical path splitting unit is provided with an aperture (not shown) and a pupil modulator 97 having the same configuration as the pupil modulator shown in FIGS. The pupil modulator 97 is intermittently fixed by a locking mechanism (for example, a click mechanism) provided near the pupil conjugate position 95. The other pupil modulator 97a is arranged near the condenser lens 57 in FIG.

  According to the present embodiment configured as described above, since the projection optical path reflected by the first optical element 66 is provided with three optical paths, even if one optical path is used as an optical path for pupil modulation, the remaining two optical paths are used. Can be used as a combination of a high-sensitivity TV camera and a high-resolution TV camera. Also, since the projection magnification of each projection optical path is equal, the size of the sample can be grasped using multiple images obtained, and the images can be superimposed. This facilitates the adjustment and comparison work, improving the usability, work efficiency, and experimental accuracy of the research realization of weak fluorescence observation and photometry.

  By making the pupil modulator 97 for the phase difference and the stereoscopic vision detachable in the optical path of the relay lens, simultaneous observation of the bright field and the phase difference and the fluorescence and the fluorescence phase difference becomes possible.

  When detecting extremely weak light, fluorescence measurement is performed after phase difference observation for sample positioning.However, since phase difference observation and fluorescence measurement can be performed with the same objective lens, there is only misalignment due to objective conversion. Measurement accuracy can be improved.

  Since the optical path splitting unit of the first optical element and the relay lens capable of pupil modulation can be attached to and detached from the microscope as an intermediate lens barrel, the system of the erecting microscope can be maintained and improved.

  Since the relay lens is divided into two groups and the intermediate lens barrel (optical path splitting unit 69) is separated by the infinite projection (light flux) portion of the image relay lens system, the observation or photographing lens barrel including the second group of the image relay lens is used. If it is used, the accuracy of the heart due to the division of the unit can be reduced and the cost can be reduced.

  The imaging lens was removed from the observation lens barrel immediately above the objective lens, and the imaging lens was provided immediately below the first optical element in the intermediate lens barrel. It is sufficient to insert the attached observation lens barrel into the microscope main body, and it is possible to minimize the influence on the system performance of the microscope and to provide a plurality of imaging optical paths having the same image magnification.

  The relay lens system capable of pupil modulation on the side reflected by the semi-transmissive prism 66b is separated from the housing 69 of the optical path splitting unit, and is made into a separate unit. The relay lens system unit can be mounted in any of three directions (optical paths 67a, b, c) if it has the same shape as the TV camera mounting mount (69c) on both sides of 69. The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

FIG. 1 is a schematic diagram showing a structure of an optical system of an inverted microscope according to a first embodiment of the present invention. FIG. 2 is a perspective view illustrating the optical system when the first embodiment is viewed from the side. FIG. 2 is a perspective view showing the optical system of the first embodiment as viewed from the front. FIG. 3 is a perspective view showing a main part of an insertion / removal mechanism of the first optical element from the lens housing in the first embodiment. FIG. 5 is a sectional view taken along line AA shown in FIG. 4. FIG. 2 is a diagram illustrating an extracted optical system according to the first embodiment. FIG. 2 is a diagram illustrating a mechanical configuration of a pupil modulator provided in the first embodiment. FIG. 8 is a sectional view taken along line AA shown in FIG. 7. FIG. 2 is a perspective view showing a discussion lens barrel incorporated in the first embodiment. FIG. 7 is a schematic diagram illustrating a structure of an optical system of an erecting microscope according to a second embodiment. FIG. 9 is a perspective view showing an optical system when the second embodiment is viewed from the side. FIG. 6 is a diagram illustrating an optical system in which another observation lens barrel is attached to the first embodiment, and a diagram illustrating a modification of the optical path deflecting device. FIG. 3 is a diagram illustrating a case where a finite design optical system is applied to the first embodiment.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 ... mirror housing, 9 ... sample, 11, 61 ... objective lens, 15, 65 ... imaging lens, 16, 66 ... 1st optical element, 16a-16c ... semi-transmissive prism, 17a-17d ... photography optical path, 22, 73: second optical element, 23: observation optical path, 26b, 97, 100: pupil modulator, 27: observation cylinder.

Claims (6)

A light source for generating illumination light,
An illumination optical system that irradiates the sample with illumination light generated by the light source,
An objective lens that is arranged to face the sample and that receives object light from the sample;
Light splitting means arranged on an optical path between a primary image formed by the objective lens and the objective lens and splitting light passing through the objective lens in three or more different directions,
An observation optical path on which the light branched by the light branching unit is incident,
And three or more photographing optical paths on which the light branched by the light branching unit is incident.
An inverted microscope, wherein one of the photographing optical paths can branch into a lower optical path of the light branching means, and the lower optical path and another photographing optical path can be used simultaneously. A light source for generating illumination light,
An illumination optical system that irradiates the sample with illumination light generated by the light source,
An objective lens that is arranged to face the sample and that receives object light from the sample;
An imaging lens that is provided on an optical path of light that has passed through the objective lens and forms an image of light that has passed through the objective lens at a predetermined position to form a primary image of the sample;
Light splitting means arranged on an optical path between the objective lens and the primary image and splitting light passing through the objective lens into three or more different directions,
An observation optical path on which the light branched by the light branching unit is incident,
And three or more photographing optical paths on which the light branched by the light branching unit is incident.
An inverted microscope, wherein one of the photographing optical paths can branch into a lower optical path of the light branching means, and the lower optical path and another photographing optical path can be used simultaneously. A light source for generating illumination light,
An illumination optical system that irradiates the sample with illumination light generated by the light source,
An objective lens that is arranged to face the sample and that receives object light from the sample;
An imaging lens that is provided on an optical path of light that has passed through the objective lens and forms an image of light that has passed through the objective lens at a predetermined position to form a primary image of the sample;
A first optical element disposed on an optical path between the objective lens and the first image and branching light passing through the objective lens in different directions;
A second optical element that is provided on the optical path of the branched light branched by the first optical element and guides the branched light incident from the first optical element in a plurality of directions including an observation optical path;
It is provided with three or more photographing optical paths into which light split by the first optical element and light passing through the first optical element and the second optical element are incident,
An inverted microscope, wherein one of the photographing optical paths can branch into a lower optical path of the second optical element, and the lower optical path and another photographing optical path can be used simultaneously.   4. The inverted microscope according to claim 1, wherein the light splitting unit or the optical element has at least a semi-transmissive prism or a dichroic mirror.   The inverted microscope according to any one of claims 1 to 3, wherein at least a part of the optical branching unit or the optical element is detachable or replaceable.   4. The inverted microscope according to claim 1, wherein the plurality of photographing optical paths have the same image magnification.

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