JPH0543111U - Epi-illumination device - Google Patents

Abstract

(57) [Summary] [Purpose] The objective is to greatly simplify the work of adjusting the amount of light that accompanies the switching of the speculum method. A first epi-illumination unit 17 for illuminating an object by passing an illumination light beam from a light source 3 and a second epi-illumination for passing an illumination light beam around the objective lens 1 to illuminate an object. The illumination unit 2 is detachably attached according to each of the microscopic methods of bright field illumination, dark field illumination, and polarized illumination, and the attached first or second epi-illumination unit 2 and 17 and the light source 3 are attached. Filter 3 in the optical path between
0 is placed. The filter 30 has a polarizing portion 32 formed in a region through which a light beam used for bright field illumination and polarized illumination passes, and a light transmitting part 33 in a region through which a light beam used for dark field illumination passes.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an epi-illumination device for a microscope, and more particularly, to improvement of a mechanism for adjusting the brightness of an observation image in bright-field illumination, dark-field illumination, and polarized illumination.

[0002]

[Prior Art]

 Conventionally, there is an epi-illumination device that enables different spectroscopic methods with the same microscope by exchanging optical members related to epi-illumination. FIG. 5 shows a dark-field illumination optical system in such a device.

In the optical system for dark field illumination, a dark field unit 2 is inserted on the optical path between the objective lens 1 and an eyepiece lens (not shown), and the illumination light from the light source 3 enters the dark field unit 2. The ND filter 4 is inserted in the filter pocket 5 and arranged on the optical path that guides the light.

The dark field unit 2 passes the illumination light flux from the light source 3 through the first diaphragm 6 and shields the central portion thereof to form a ring-shaped light flux. The ring-shaped light beam is bent toward the objective lens side by the ring mirror 7, passes through the first diaphragm 8, and then passes through the periphery of the objective lens 1 to illuminate the object. Then, the object light incident on the objective lens 1 from the object side is guided to the eyepiece lens side through the separation tube 9 provided in the central opening of the ring mirror 7.

The first diaphragm 6 has a shape shown in FIG. 6A, and a light-shielding portion 11 corresponding to the diameter of the bright-field illumination light flux is provided in the central portion thereof, and the ring-shaped light flux is provided around the light-shielding portion 11. A ring-shaped through hole 12 for forming is formed. The second diaphragm 8 has a shape shown in FIG. 6B, and a central opening 13 through which the dark-field illumination luminous flux and the object light pass is formed in the central portion and has a ring shape with a predetermined distance. A ring-shaped through hole 14 is formed to regulate the diameter of the light flux. Further, the ND filter 4 has a shape shown in FIG. 6C, has an ND region 15 having the same diameter as the light shielding part 11 in the central part, and has the same shape as the ring-shaped through hole 12 around the ND region 15. There is a ring-shaped plain threaded portion 16. Further, FIG. 7 shows an optical system at the time of bright field illumination.

In the bright field illumination optical system, a bright field unit 17 is inserted on an optical path between the objective lens 1 and an eyepiece lens (not shown), and the illumination light from the light source 3 is guided to the bright field unit 17. The ND filter 4 is arranged on the optical path similarly to the above.

The bright field unit 17 makes the illumination light flux from the light source 3 into a circular light flux having a predetermined diameter by the third diaphragm 18, bends it toward the objective lens side by the half mirror 19, and passes it through the fourth diaphragm 20 to make the objective. Illuminate the object through the lens 1. Then, the object light incident on the objective lens 1 from the object side is transmitted through the half mirror 19 and guided to the eyepiece lens side.

Dark field illumination requires a very bright light source for observation because the observed image is much darker than bright field illumination. However, when the dark field is switched to the bright field in that state, the bright field illumination receives a larger amount of light than the dark field illumination, and the bright field observation image is too bright. Therefore, at the time of bright field illumination, the light amount of the clear field illumination light is reduced by the ND filter 4.

Further, even when the ND filter 4 is left attached during dark field illumination, the light flux actually used for dark field illumination passes through the transparent portion 16, so dark field illumination is performed. The amount of light is not reduced by the ND filter 4. Further, FIG. 8 shows an optical system for polarized illumination.

In this case, the bright field unit 17 is used, and a polarizer 21 made of a polarizing plate is mounted in a filter pocket 22 on the optical path from the light source 3 to the bright field unit 17. Further, on the eyepiece side emission surface of the bright field unit 17, an analyzer 23 composed of a polarizer 21 and a polarizing plate that makes the polarization direction orthogonal to each other is arranged.

Since the polarizer 21 and the analyzer 23 have the same configuration, the configuration will be described using the polarizer 21 as an example. As shown in FIG. 9, the polarizer 21 arranges a circular polarization plate 21a having the same diameter as the opening diameter of the third diaphragm 18 in the passage of the illumination light flux and acts so as to pass only the vibration component in the predetermined direction. ..

Since polarized illumination passes the illumination light flux and the object light through the respective polarizing plates, the observed image is very dark like the dark field illumination. Therefore, it is necessary to use the bright field unit 17 capable of capturing a large amount of light and remove the ND filter 21 from the optical path.

In the epi-illumination device configured as above, when switching from dark-field illumination to bright-field illumination, the dark-field unit 2 is replaced with the bright-field unit 17 with the ND filter 4 still attached. When switching from bright field illumination to polarized illumination, the ND filter 4 is removed and the polarizer 21 and analyzer 23 are attached. Furthermore, when switching from dark-field illumination to polarized illumination, it is necessary to replace the dark-field unit 2 with the bright-field unit 17, remove the ND filter 4, and attach the polarizer 21 and the analyzer 23.

[0014]

[Problems to be solved by the device]

 In this way, the epi-illumination device that made it possible to switch among dark-field illumination, bright-field illumination, and polarized illumination was used to replace the epi-illumination unit and to replace the ND filter 4 and polarizer 21 according to the speculum method. Was required and the work was complicated.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an epi-illumination device capable of significantly simplifying the work of exchanging optical members associated with the switching of the speculum method. ..

[0016]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention provides a first epi-illumination unit that illuminates an object by passing an illumination light flux from a light source through an objective lens, or an illumination light flux from the light source of the objective lens. The second epi-illumination unit, which passes through the surroundings and illuminates the object, is installed according to each of the bright-field illumination, dark-field illumination, and polarized illumination spectroscopic methods. Polarized light formed in a region through which the light flux used for the bright field illumination and polarized illumination passes, which is disposed so as to block the optical path between the first or second epi-illumination unit mounted as described above and the light source. And a light-transmitting portion formed in a region through which a light flux used for night-vision illumination passes.

[0017]

[Action]

 According to the present invention, by taking the above-mentioned measures, in the case of dark field illumination, the light flux used for dark field illumination out of the illumination light flux from the light source passes through the light transmitting portion of the filter and becomes the first light flux. It is incident on the second epi-illumination unit. Then, the object is illuminated through the periphery of the objective lens.

When switching from dark-field illumination to bright-field illumination, the second epi-illumination unit is replaced with the first epi-illumination unit. The illumination light flux from the light source is reduced in amount when passing through the polarizing part of the filter, so that good bright field observation can be performed with a light source having the same light intensity as dark field illumination without using an ND filter.

Further, when switching from the bright field illumination to the polarized illumination, since the polarization part of the filter functions as a polarizer, if the analyzer is arranged on the optical path between the first epi-illumination unit and the eyepiece lens, Polarized light observation becomes possible.

[0020]

【Example】

 An embodiment of the present invention will be described below.

FIGS. 1A to 1C show optical systems of an epi-illumination device according to an embodiment for dark field illumination, clear field illumination, and polarized illumination, respectively. The parts having the same functions as those of the optical system described in FIGS. 5 to 8 are designated by the same reference numerals, and detailed description thereof will be omitted.

In the case of dark-field illumination, the epi-illumination device of the present embodiment has a dark-field unit 2 as a second epi-illumination unit arranged on the objective optical axis and On the optical path between the light source 3 and the light source 3, the filter 30 having the configuration shown in FIG. Further, in the case of bright field illumination, the bright field unit 17 as the first epi-illumination unit is arranged on the objective optical axis, and the filter 30 is also arranged on the optical path as it is. Further, in the case of polarized illumination, the analyzer 23 is arranged so as to face the optical system for bright-field illumination, and the exit surface of the bright-field unit 17 on the eyepiece side.

The filter 30 has a circular polarization section 32 having the same diameter as the third diaphragm 18 for limiting the light flux diameters of the bright field illumination and the polarized illumination on the glass substrate, and the periphery of the polarization section 32. A light-transmitting portion 33 having the same shape as the ring-shaped through hole 12 of the first diaphragm 6 is formed therein. The other area 34 is a light shielding area.

When the filter 30 is arranged vertically to the optical path, the light transmitting portion 33 coincides with the penetrating ring opening 12 of the first diaphragm 6 during dark field illumination, and the polarizing portion 32 covers bright field illumination and dark field illumination. It coincides with the opening of the third diaphragm 18 during polarized illumination. Next, the operation of this embodiment configured as described above will be described.

First, in the case of dark field illumination, an optical system is configured as shown in FIG. In the optical system as described above, of the illumination light flux emitted from the light source 3, the light passing through the polarization unit 32 of the filter 30 is blocked by the first diaphragm 6 of the dark field unit 2 and transmitted through the filter 30. The light flux that has passed through the light section 33 passes through the penetrating ring port 12 of the first diaphragm 6. Then, the object is illuminated by being bent by the ring mirror 7 and passing around the objective lens 1.

When switching from dark-field illumination to bright-field illumination, the dark-field unit 2 is replaced with a bright-field unit, and the optical system shown in FIG. 1B is obtained. In such an optical system, of the illumination light flux emitted from the light source 3, the light flux that has passed through the light transmitting portion 33 of the filter 30 is blocked by the third diaphragm 18 of the bright field unit 17, and the light polarizing portion 32 of the filter 30 is blocked. The passed light flux passes through the third diaphragm 18.

At this time, since the light flux passing through the third diaphragm 18 is only the vibration component in one direction that has passed through the polarization section 32, the light amount is greatly reduced. The light flux with the reduced amount of light is bent by the half mirror 19 and passes through the objective lens 1 to illuminate an object. Therefore, even if the light intensity of the light source 3 is the same as in the dark field, the inconvenience that the observed image is too bright is prevented.

Next, when switching from the bright field illumination to the polarized illumination, the analyzer 23 is arranged so as to face the exit surface of the bright field unit 17 on the eyepiece side, so that the optical system shown in FIG.

In the case of this polarized illumination, the polarization unit 32 of the filter 30 functions as a polarizer, and the relationship between the polarizer and the half mirror 19 of the analyzer 23 is shown in FIG. In this embodiment, the vibration direction of the polarization unit 32 as the polarizer is perpendicular to the paper surface, and the vibration direction of the analyzer is parallel to the paper surface. In such an optical system, of the illumination light fluxes from the light source 3, the light fluxes that have passed through the light transmitting portion 33 of the filter 30 as they are are shielded by the third diaphragm 18 and only the polarized light fluxes that have passed through the polarizing portion 32 are It is bent by the mirror 19 to illuminate the object. Object light corresponding to the polarization characteristics of the observation object passes through the objective lens 1 and the half mirror 19 and enters the analyzer 23.

Since the vibrating direction of the polarization unit 32 as the polarizer and the vibrating direction of the analyzer 23 are orthogonal to each other, the degree of weakening of the polarized light beam for illumination is reduced, and the crossed Nicols can be observed. Becomes Next, when switching from polarized illumination to darkfield illumination, the analyzer 23 is removed and the darkfield unit 2 is replaced. The switching work is completed by these two works.

As described above, according to the present embodiment, since the filter 30 having the polarization part 32 and the translucent part 33 is arranged on the optical path between the light source 3 and the epi-illumination units 2 and 17, the mirror 30 is provided. It is possible to greatly simplify the work of exchanging the optical member according to the law.

For example, when switching from bright-field illumination to polarized illumination, it is possible to reduce the work of mounting the polarizer and the work of removing the ND filter, which are conventionally required. Further, if the polarized illumination is switched to the dark-field illumination, it is possible to reduce the work of removing the polarizer and the work of mounting the ND filter, which have been conventionally required. Further, in this embodiment, since it is not necessary to dispose the ND filter on the optical path, it is possible to reduce the filter pocket.

Since it is difficult to adjust to a delicate density by the light-reducing action of the polarization section 32, as shown in FIG. 3, a synthetic filter in which the ND member 35 for adjusting the light quantity is further attached to the polarization section 32 is used. 36 may be used instead of the filter 30. By using the synthesizing filter 36, a more appropriate density can be realized.

Further, by disposing the analyzer 23 rotatably, it is possible to adjust the deviation in the vibration direction with respect to the polarizer, and it is possible to further increase the EF value during crossed Nicols.

[0035]

[Effect of the device]

 As described in detail above, according to the present invention, it is possible to provide an epi-illumination device that can greatly simplify the work of exchanging optical members associated with the adjustment of the light amount by switching the speculum method.

[Brief description of drawings]

FIG. 1 is a diagram showing an optical system for each speculum method of an epi-illumination device according to an embodiment of the present invention.

FIG. 2 is a plan view of a filter included in an epi-illumination device according to an embodiment.

FIG. 3 is a diagram showing a modified example of a filter.

FIG. 4 is a diagram showing an arrangement relationship between a polarizer and an analyzer.

FIG. 5 is a diagram showing an optical system of a conventional epi-illumination device during dark field illumination.

FIG. 6 is a plan view of first and second diaphragms and an ND filter.

FIG. 7 is a diagram showing an optical system of a conventional epi-illumination device during bright field illumination.

FIG. 8 is a diagram showing an optical system of a conventional epi-illumination device during polarized illumination.

FIG. 9 is a plan view of a polarizer and an analyzer.

[Explanation of symbols]

1 ... Objective lens, 2 ... Dark field unit, 3 ... Light source, 17
... bright field unit, 30 ... filter, 32 ... polarization part,
33 ... Translucent part.

Claims (1)

[Scope of utility model registration request] 1. A first epi-illumination unit for illuminating an object by passing an illumination light beam from a light source through an objective lens, and a first epi-illumination unit for illuminating an object by passing an illumination light beam from the light source around the objective lens. An epi-illumination device in which two epi-illumination units are detachably attached according to each of the bright-field illumination, dark-field illumination, and polarized illumination spectroscopic methods. 2 is used so that it is arranged so as to block the optical path between the epi-illumination unit and the light source, and is formed in a region through which the luminous flux used for the bright field illumination and polarized illumination passes, and the dark field illumination. An epi-illumination device comprising a filter having a light transmitting portion formed in a region through which a light beam passes.