JP2010008646A - Microscope device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microscope device for obtaining high resolution observation images and epi illumination of a sufficient amount by having high contrast. <P>SOLUTION: The microscope device 1 includes: two observation optical systems 10 including an objective lens 11 condensing light from an object O; and an illumination optical system 20 of an epi illumination device for illuminating the object O through the objective lens 11. The illumination optical system 20 includes: two optical paths 29 for having an aperture diaphragm AS respectively and guiding illumination light from a light source S arranged in the illumination optical system 20 to the objective lens 11; and an optical path division element 23 arranged at a conjugate position with the light source S in the illumination optical system 20 and guiding the illumination light in the two optical paths 29. When being seen from a direction extending an optical axis of the objective lens 11 to an image side, the two observation optical systems 10 are substantially symmetrically arranged by centering the optical axis of the objective lens 11. The two optical paths 29 of the illumination optical system 20 are substantially symmetrically arranged to a straight line perpendicular to the optical axis of the two observation optical systems 10 and in substantially parallel to the optical axis of the two observation optical systems. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a microscope apparatus.

  A parallel stereomicroscope, which is an example of a microscope apparatus, collects light emitted from a test object (specimen) with a single objective lens and then divides the light into two observation optical systems, thereby providing parallax, Observation is possible. The stereomicroscope having such a configuration uses an imaging optical system in which an afocal zoom optical system and an imaging lens are combined.

In such a stereoscopic microscope, when the object to be examined is incidentally illuminated, the illumination light is generally introduced from the middle of the observation optical system (the image side of the imaging optical system or the image side of the objective lens). Has been. In recent years, a configuration has been proposed in which an illumination optical system using an epi-illumination device is provided separately from the observation optical system, and the object to be examined is illuminated through a common objective lens (see, for example, Patent Literature). This is because an observation optical system that requires high imaging performance generally has a complicated lens configuration. Therefore, by using an illumination optical system having a relatively simple configuration different from the observation optical system, ghost, flare, Moreover, in the case of fluorescence observation, it is for preventing the contrast fall by the autofluorescence in the observation optical system by excitation light.
JP-T-2001-516071

  However, in an epi-illumination apparatus in which an illumination optical system different from the observation optical system is arranged and illuminates the object to be examined through a common objective lens, the area through which the observation light is transmitted and the illumination light are transmitted through one objective lens. Since it must be divided into areas that transmit, if the priority is given to the optical performance of the observation optical system, it is not possible to irradiate the test object with sufficient illumination light, on the contrary, if priority is given to securing the amount of illumination light, There was a problem that the imaging performance of the observation optical system deteriorated.

  The present invention has been made in view of such a problem, and a microscope apparatus capable of obtaining an observation image with high contrast and high resolution and epi-illumination with a sufficient amount of light while having optical performance equivalent to that of the prior art. The purpose is to provide.

  In order to solve the above problems, a microscope apparatus according to the present invention includes two observation optical systems including an objective lens that collects light from a test object, and an epi-illumination that illuminates the test object via the objective lens. And a lighting device. Each of the illumination optical systems constituting the epi-illumination apparatus has an aperture stop, and includes two optical paths for guiding illumination light from a light source disposed in the illumination optical system to the objective lens, and the illumination optical system. And an optical path dividing element that is arranged in the vicinity of the light source or at a position conjugate with the light source and guides the illumination light into the two optical paths. When viewed from the direction in which the optical axis of the objective lens is extended to the image side, the two observation optical systems are arranged substantially symmetrically about the optical axis of the objective lens, and the two optical paths of the illumination optical system are: They are arranged substantially symmetrically with respect to a straight line perpendicular to the optical axes of the two observation optical systems and substantially parallel to the optical axes of the two observation optical systems.

Such microscopes apparatus, the light source side pupil diameter of the illumination optical system and phi _PI, when a light source image size to be formed in the vicinity of the light source side pupil position illumination optical system and a phi _SI, the following equation 1.5φ _PI < φ _SI
It is preferable to satisfy the following conditions.

  In such a microscope apparatus, the illumination optical system preferably includes a relay optical system that forms a light source image in the vicinity of the position where the optical path splitting element is disposed in the illumination optical system.

  At this time, it is preferable that the relay optical system in the illumination optical system has a fly-eye lens and forms a light source image at a position conjugate with the light source in the illumination optical system via the fly-eye lens.

At this time, when the light source side pupil diameter of the illumination optical system and phi _PI, and the exit side effective diameter of the fly-eye lens and phi _FI, the following equation 1.5φ _{PI <φ FI}
It is preferable to satisfy the following conditions.

  In such a microscope apparatus, an illumination variable magnification optical system for changing the light beam diameter of each of the two light beams divided by the aperture stop and the optical path dividing element is provided in the two optical paths of the illumination optical system. It is preferable that they are arranged.

  In such a microscope apparatus, the optical path splitting element is preferably disposed at a position substantially conjugate with the aperture stop.

  Furthermore, in such a microscope apparatus, the optical path splitting element is preferably composed of a plurality of reflective optical elements. Alternatively, the optical path splitting element is preferably composed of a plurality of glass blocks arranged to be inclined with respect to the optical axis of the illumination optical system.

  When the microscope apparatus according to the present invention is configured as described above, it is possible to provide a microscope apparatus that can obtain an observation image with a high contrast and a high resolution and an epi-illumination with a sufficient amount of light.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. First, the configuration of a stereomicroscope will be described as an example of the microscope apparatus according to the present embodiment with reference to FIG. The stereomicroscope 1 includes an observation optical system 10 including an objective lens 11 for observing an image of an object to be examined O (hereinafter referred to as “object O”), and an illumination optical system 20 that irradiates the object O with illumination light. And an epi-illumination device. The observation optical system 10 includes, in order from the object O side, an objective lens 11 and a zoom optical system (not shown) (this zoom optical system changes the diameter of the substantially parallel light beam emitted from the objective lens 11 and emits it as a substantially parallel light beam. And an imaging lens (not shown), and an observer can observe the object O with the naked eye via an eyepiece (not shown) It can be converted into a digital image by an image pickup device (CCD or the like) arranged at the focal plane or its conjugate position. Since the stereomicroscope 1 is a parallel stereomicroscope, an imaging optical system including two afocal zoom systems and an imaging lens arranged in parallel with each other is provided for one objective lens 11. ing. An aperture stop is provided in each afocal zoom system.

  On the other hand, the illumination optical system 20 includes a light source S, a collector lens 21, a first field stop FS1, and a relay lens 22 in order from the light source side, and forms a light source image at a position conjugate with the light source S. 28, an optical path splitting element 23, a field lens 24, a second field stop FS2, an illumination imaging lens 25, and an illumination variable magnification optical system 26. The illumination optical system 20 also includes two field lenses 24, a second field stop FS2, an illumination imaging lens 25, and an illumination variable magnification optical system 26, and two optical paths 29 arranged in parallel to each other. Is forming. Here, the illuminating variable magnification optical system 26 is arranged in the illumination optical system 20, but this changes the observation field when the observation magnification is changed by the zoom optical system arranged in the observation optical system 10. This is for adjusting the illumination range. When the observation field is wide, the illumination range is wide and uniform illumination according to the observation field. When the observation magnification is high and the observation field is narrow, the illumination range is narrow and the numerical aperture (NA) of the illumination light is increased. Bright illumination can be performed.

  In the illumination optical system 20 configured as described above, the illumination light emitted from the light source S is converted into a substantially parallel light beam by the collector lens 21, and then condensed by the relay lens 22, or the tip P or the optical path dividing element 23. An image of the light source S is formed in the vicinity thereof. The optical path splitting element 23 is a first reflective optical element (for example, a mirror) 23a that spreads radially around the tip P on the optical axis, and a second reflective optical element 23a that is disposed so as to face the first reflective optical element 23a. The reflecting optical element 23b is combined with each other, and the light beam (image of the light source S) incident from the tip P side is divided into two light beams. The light beams split by the optical path splitting element 23 into two optical paths 29 are converted into substantially parallel light beams through the field lens 24, the illumination imaging lens 25, and the illumination variable magnification optical system 26, respectively. The light enters the optical system 10, passes through the objective lens 11, and is irradiated onto the object O. That is, the stereomicroscope 1 is configured so that the illumination light emitted from the illumination optical system 20 is incident on the object O via the objective lens 11 of the observation optical system 10. Here, the tip P of the optical path splitting element 23 is conjugate with the light source S, and is further disposed at a position substantially conjugate with the aperture stop AS in the variable magnification optical system 26 for illumination. That is, the tip P of the optical path dividing element 23 is a pupil conjugate position.

  As shown in FIG. 2, the two observation optical systems 10 arranged in parallel with each other transmit the effective diameter OP of the objective lens 11 when viewed from the direction in which the optical axis of the objective lens 11 extends to the image side. The light beam VP is disposed substantially symmetrically with respect to the optical axis (center) of the objective lens 11. That is, the straight line connecting the centers of the two light beams VP is disposed so as to pass through the optical axis of the objective lens 11 or the vicinity thereof. The light beam IP passing through the objective lens 11 by the two optical paths 29 (field lens 24, illumination imaging lens 25, and illumination variable magnification optical system 26) constituting the illumination optical system 20 is converted into the two observation optical systems 10. The two observation optical systems 10 are substantially symmetrical with respect to a straight line perpendicular to the center line of the light beam VP passing through the two observation optical systems 10 (the optical axis of the observation optical system 10). Are arranged substantially parallel to the optical axis. Therefore, a straight line perpendicular to the center line of the two light beams IP passes through the optical axis of the objective lens 11 or the vicinity thereof, and is substantially the same as a straight line perpendicular to the center line of the two light beams VP (the optical axis of the observation optical system 10). It arrange | positions so that it may orthogonally cross.

  When the observation optical system 10 and the illumination optical system 20 are arranged as described above with respect to the objective lens 11, the luminous flux VP passing through the two observation optical systems 10 passing through the effective diameter OP of the objective lens 11 is most efficient. They can be arranged well and a bright image of the object O can be observed. Even if the observation optical system 10 is arranged in this way, the light flux IP that passes through the two illumination optical systems 20 in an area where the light flux that passes through the observation optical system 10 is not used within the effective diameter OP of the objective lens 11. Since the object O can be irradiated with sufficient illumination light and the light beams VP and IP passing through the observation optical system 10 and the illumination optical system 20 can be arranged so as not to overlap with each other, In the case of ghost and flare generation and fluorescence observation, it is possible to prevent a decrease in contrast due to autofluorescence in the observation optical system 10 due to excitation light.

  As shown in FIG. 3A, if the illumination optical system is not divided and only the light beam IP passing through one illumination optical path is illuminated, sufficient illumination light can be irradiated to the sample. First, as shown in FIG. 3B, the light beam VP passing through the observation optical system without dividing the optical path of the illumination optical system is shifted from the center of the effective diameter OP of the objective lens to pass through the illumination optical system. Increasing the IP diameter can increase the amount of illumination light applied to the sample, but is not preferable because the asymmetric aberration of the objective lens 11 affects the optical performance of the observation optical system.

Generally, in the epi-illumination, the intensity of illumination light is proportional to the square of the numerical aperture (NA) on the object side. This means that when the focal length of the objective lens 11 is the same, the intensity of the illumination light is proportional to the area of the pupil. FIG. 4 shows a light source side pupil image PI of the illumination optical system 20 and a light source image SI formed in the vicinity of the light source side pupil position. In the stereomicroscope 1 having the above-described configuration, when the illuminating variable magnification optical system 26 is on the high magnification side, the exit pupil diameter φ _PI viewed from the pupil conjugate position P side is reduced, and as a result, the image of the light source S is reduced. smaller than the diameter φ _SI. Here, when the size of the light source image SI (diameter φ _SI ) is twice or more the pupil diameter φ _PI , the light source image SI can be divided into two without limiting the pupil diameter φ _PI of the illumination optical system 20. Then, when the light source image divided into two is projected in the vicinity of the pupil position of the illumination optical system 20 and the object to be examined (object O) is illuminated via the objective lens 11, the area of the pupil is doubled. Bright lighting can be performed. In particular, in the case of the parallel stereomicroscope 1 configured as described above, since there are two observation optical systems 10 due to the mechanism, the illumination light beam is obtained by dividing the light source image into a region on the pupil plane of the objective lens 11 where the observation light does not pass. Can be easily introduced into the two illumination optical systems. From the above, in the stereomicroscope 1 having such a configuration, by a light source image size phi _SI and the light source-side pupil diameter phi _PI of the illumination optical system 20 satisfies the following condition (1), the light source image SI It is possible to effectively divide the object, and it is possible to illuminate the test object (object O) more brightly.

1.5φ _PI <φ _SI (1)

  As described above, when the optical path splitting element 23 is located at a position substantially conjugate with the aperture stop AS of the illumination variable magnification optical system 26 of the illumination optical system 20, the use efficiency of illumination light is increased, but zooming is performed. Thus, the exit pupil position of the illuminating variable magnification optical system 26 changes. However, if the conditional expression (1) is satisfied, the light source image SI can be effectively divided and irradiated onto the object O.

[Modification]
As described above, when the diameter phi _SI diameter phi _PI and the light source image SI of the exit pupil image PI satisfies the conditional expression (1), it is possible to effectively divide the source image SI, the diameter of the light source S it is possible to effectively divide the light source image SI in the a (diameter phi _SI of the light source image SI) to increase the low power end side. However, when the diameter of the light source S is increased, the opening angle is widened, and as a result, the central portion with the optical axis as the center becomes bright, but the peripheral portion becomes dark and uneven illuminance occurs. Here, in order to eliminate this illuminance unevenness, an actual microscope 1 ′ having a configuration in which a fly-eye lens 27 is arranged in place of the relay lens 22 in the relay optical system 28 in FIG. 1 will be described with reference to FIG. The actual microscope 1 ′ shown in FIG. 5 has an observation optical system 10 and an illumination optical system 20 ′. The same components as those of the actual microscope 1 shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The illumination optical system 20 ′ includes, in order from the light source side, the light source S, a relay optical system 28 including a collector lens 21 and a fly-eye lens 27, an optical path dividing element 23 ′, two field lenses 24, and two first lenses. A two-field stop FS2, two illumination imaging lenses 25, and two illumination variable optical systems 26 are provided. Here, the fly-eye lens 27 is a lens configured by arranging a plurality of microlenses in an array. In the stereomicroscope 1 ′ shown in FIG. 5, the optical path splitting element 23 ′ has two glass blocks (for example, parallel prisms) inclined with respect to the optical axis, and 2 beams emitted from the fly-eye lens 27. The light beam 29 is divided into two light beams and each optical path 29 is shifted to an appropriate distance. The arrangement of the light beam VP that passes through the observation optical system 10 and the light beam IP that passes through the illumination optical system 20 with respect to the effective diameter OP of the objective lens 11 described with reference to FIG.

  In this illumination optical system 20 ′, the illumination light emitted from the light source S is converted into a substantially parallel light beam by the collector lens 21, and then condensed by each microlens constituting the fly-eye lens 27. In the system 20 ', a light source image is formed at the position where the optical path splitting element 23' is disposed (end surface on the fly-eye lens exit side). The light beam emitted from the fly-eye lens 27 is divided into two light beams by an optical path splitting element 23 ′ disposed in the vicinity of the object-side surface of the fly-eye lens 27, and each of the divided light beams is a field lens. 24, is converted into a substantially parallel light beam through the illumination imaging lens 25 and the illumination variable magnification optical system 26, enters the observation optical system 10, passes through the objective lens 11, and is irradiated onto the object O. Note that the first field stop FS1 in the stereomicroscope 1 shown in FIG. 1 corresponds to the surface on the fly-eye lens 27 light source S side in the stereomicroscope 1 ′ shown in FIG. Is the pupil conjugate plane P. That is, the surface FS1 on the light source S side of the fly-eye lens 27 is conjugate with the second field stop FS2, and the surface P on the objective lens 11 side of the fly-eye lens 27 is an aperture in the light source S and the illumination variable magnification optical system 26. It is conjugate with the aperture stop AS.

As described above, since the fly-eye lens 27 is configured by arranging a plurality of microlenses in an array, the light source images from the respective microlenses overlap on the sample surface (on the object O), and the unevenness in illuminance is canceled and uniform. Lighting can be performed. Therefore, even if the diameter of the light source S is increased, the illuminance unevenness can be reduced and the effective system of the pupil conjugate plane can be increased, so that the light source image can be more easily divided. FIG. 6 shows a light source image FI at the light source side pupil position in the stereomicroscope 1 ′ shown in FIG. Even in the stereomicroscope 1 ′, when the exit pupil diameter is ½ or less of the diameter of the light source image, the light source image can be divided effectively, and the object O can be illuminated more brightly. When the fly-eye lens 27 is used, there is no illuminance unevenness even when the diameter of the light source S is increased as described above, so that the pupil can be effectively divided even on the low magnification side of the variable magnification optical system 26 for illumination. . Specifically, the stereomicroscope 1 ', that the diameter phi _FI light source images FI and the light source-side pupil diameter phi _PI of the illumination optical system 20 (shown in FIG. 2) satisfies the following condition (2) Thus, the light source image FI can be divided effectively, and the object O can be illuminated more brightly.

1.5φ _PI <φ _FI (2)

  As described above, in this microscope apparatus 1, 1 ′, in addition to the observation optical system 10, two illumination optical systems 20, 20 ′ are arranged so as to sandwich the two observation optical systems 10, and this illumination is performed. A light source image is formed in the vicinity of the pupil position on the light source side of the optical system 20, 20 ′, the light source image is spatially divided, and each light beam is separated from the object O by the two illumination optical systems 20, 20 ′ and the objective lens 11. Therefore, the area of the pupil of the illumination optical systems 20 and 20 'is doubled, and brighter illumination can be performed. Further, since the observation optical system 10 can be arranged symmetrically with respect to the center of the objective lens 11, the imaging performance of the observation optical system 10 is not impaired. Further, since the light beam VP passing through the observation optical system 10 and the light beam IP passing through the illumination optical systems 20 and 20 ′ can be arranged so as not to overlap in the objective lens 11, generation of ghosts and flares, In the case of fluorescence observation, it is possible to prevent a decrease in contrast due to autofluorescence in the observation optical system 10 due to excitation light.

It is a lens block diagram which shows the structure of the stereomicroscope based on this invention. It is explanatory drawing for demonstrating the arrangement | positioning method of the illumination optical system with respect to an objective lens, and an observation optical system. It is explanatory drawing for demonstrating another arrangement | positioning method of the illumination optical system with respect to an objective lens, and an observation optical system, Comprising: (a) shows when an illumination optical system is made into one, (b) shows observation optical diameter. A case where the luminous flux of the illumination optical diameter is increased by shifting the position is shown. It is explanatory drawing which shows the light source image in the light source side pupil position in the said stereomicroscope. It is a lens block diagram which shows the structure of the modification of the stereomicroscope based on this invention. It is explanatory drawing which shows the light source image in the light source side pupil position in the said modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1 'Stereomicroscope (microscope apparatus) 10 Observation optical system 11 Objective lens 20, 20' Illumination optical system 23, 23 'Optical path dividing element 26 Variable magnification optical diameter for illumination AS Aperture stop 27 Fly eye lens 28 Relay optical system 29 Optical path O Object (test object)

Claims (9)

Two observation optical systems including an objective lens for condensing light from a test object;
An epi-illumination device that illuminates the object to be examined through the objective lens,
The illumination optical system constituting the epi-illumination device is
Two optical paths each having an aperture stop and guiding illumination light from a light source disposed in the illumination optical system to the objective lens;
An optical path dividing element that is disposed in the vicinity of the light source in the illumination optical system or at a position conjugate with the light source, and that guides the illumination light into the two optical paths;
When viewed from the direction in which the optical axis of the objective lens is extended to the image side, the two observation optical systems are arranged substantially symmetrically about the optical axis of the objective lens, and the 2 of the illumination optical system The microscope apparatus, wherein the two optical paths are arranged substantially symmetrically with respect to a straight line perpendicular to the optical axis of the two observation optical systems and substantially parallel to the optical axes of the two observation optical systems. A light source side pupil diameter phi _PI of the illumination optical system, when a light source image size to be formed on the light source side pupil position near the illumination optical system and phi _SI, the following equation 1.5φ _{PI <φ SI}
The microscope apparatus according to claim 1, wherein the following condition is satisfied.   The microscope apparatus according to claim 1, wherein the illumination optical system includes a relay optical system that forms a light source image in the vicinity of a position where the optical path dividing element is disposed in the illumination optical system.   The relay optical system in the illumination optical system has a fly-eye lens, and forms the light source image at a position conjugate with the light source in the illumination optical system via the fly-eye lens. The microscope apparatus according to claim 3. The source-side pupil diameter of the illumination optical system and phi _PI, when an exit side effective diameter of the fly-eye lens was set to phi _FI, the following equation 1.5φ _{PI <φ FI}
The microscope apparatus according to claim 4, wherein the following condition is satisfied.   In the two optical paths of the illumination optical system, an illuminating variable magnification optical system for changing the light beam diameter of each of the two light beams divided by the aperture stop and the optical path splitting element is disposed. The microscope apparatus according to any one of claims 1 to 5.   The microscope apparatus according to claim 1, wherein the optical path splitting element is disposed at a position substantially conjugate with the aperture stop.   The microscope apparatus according to claim 1, wherein the optical path dividing element includes a plurality of reflective optical elements.   The microscope apparatus according to any one of claims 1 to 7, wherein the optical path dividing element includes a plurality of glass blocks arranged to be inclined with respect to the optical axis of the illumination optical system.

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