JP5581752B2 - Autofocus optical device, microscope - Google Patents

Description

  The present invention relates to an autofocus optical device and a microscope having the same.

  Conventionally, an auto-focus (hereinafter simply referred to as AF) optical system and AF detection optics for focusing an objective lens on a predetermined position of a specimen placed on a stage and maintaining the focused state There is known a microscope in which an AF optical device including a system is arranged between an objective lens and a second objective lens (see, for example, Patent Document 1). However, in the above microscope, there is a limit to the number of optical devices that can be arranged between the revolver and the second objective lens in order to maintain operability and the like, and the number necessary for observation when the AF optical device is arranged in this portion. However, there is a problem that it is impossible to arrange various optical devices (for example, a fluorescent illumination device, an epi-illumination device, a laser illumination device, etc.) and it becomes impossible to deal with various observations. In order to solve this problem, the AF optical device is integrated with a revolver on which a plurality of objective lenses are placed, and the revolver is moved up and down along the optical axis based on a signal from the AF optical device to prepare a sample. A microscope having an AF mechanism that focuses and maintains a focused state has been proposed (see Patent Document 2).

JP-A-11-344675 JP-A-10-253895

  When the AF optical device is arranged integrally with the revolver as in a conventional microscope, the revolver is provided with the AF optical device, so that there is a problem that a quick focusing operation on the specimen becomes difficult.

  The present invention has been made in view of the above problems, and an AF optical apparatus that allows an agile focusing operation on a specimen without the AF optical apparatus occupying between the revolver and the second objective lens. Another object is to provide a microscope having the same.

In order to solve the above problems, the present invention provides:
A first mirror that is provided inside a revolver that holds the objective lens and that is disposed on the optical axis of the objective lens and reflects autofocus light;
An autofocus illumination optical system that irradiates the specimen with the autofocus light deflected by the first mirror via the objective lens;
An autofocus detection optical system for detecting the autofocus light from the specimen through the objective lens;
A relay optical system shared by at least a part of the autofocus illumination optical system and the autofocus detection optical system;
The autofocus light is shared by the illumination optical system and the detection optical system, the first mirror and the relay optical system,
The autofocus illumination optical system and the autofocus detection optical system are arranged on a microscope mirror base separated from the revolver,
The optical axis of the relay optical system and the optical axis of the objective lens are separated,
There is provided an autofocus device characterized in that a focusing operation is performed by driving the objective lens held by the revolver along the optical axis of the objective lens .

  The present invention also provides a microscope having the autofocus optical device.

  According to the present invention, it is possible to provide an AF optical device that allows an agile focusing operation on a specimen without occupying the space between a revolver and a second objective lens, and a microscope having the same. Can do.

The side view containing the partial cross section of the microscope which concerns on this embodiment. FIG. 2 is a cross-sectional view taken along line AA in FIG. 1 and a part of an optical path of the AF optical device. FIG. 2 is a cross-sectional view taken along line B-B in FIG. The AF illumination optical unit and the AF detection optical unit are shown in a cross-sectional view taken along the line CC in FIG.

  A microscope having an AF optical device according to an embodiment of the present application will be described below with reference to the drawings. The following embodiments are only for facilitating the understanding of the invention, and excluding additions and substitutions that can be performed by those skilled in the art without departing from the technical idea of the present invention. It is not intended. In the following description, an inverted microscope will be described as a representative, but it goes without saying that the same applies to an upright microscope.

  1 to 3, an inverted microscope 1 according to this embodiment includes a microscope base (hereinafter referred to as a base) 10, a stage unit 20, a transmission illumination column 30, an observation unit 40, and epi-fluorescence. A unit 50, a laser fluorescence unit 60, and a camera 70 are provided.

  The base unit 10 includes a second objective lens 11, a mirror 12 and a mirror 13 that guide light from the second objective lens 11 to the observation unit 40, an AF optical device 80 (to be described later), and a motor 14 that is used for vertical movement of the revolver 23. Etc.

  Further, the mirror 12 is slidable in a direction perpendicular to the optical axis (a direction perpendicular to the paper surface of FIG. 1). The optical axis here means an optical axis connecting an objective lens 22 and a second objective lens 11 described later. In the present specification, this optical axis may also be referred to as the optical axis of the objective lens 22. By retracting the mirror 12 from the optical axis, the light from the second objective lens 22 is collected by the camera 70 and a sample image or the like can be observed with a display device (not shown).

  Further, by inserting an optical member provided with a half mirror 15 on the second objective lens 11 side of the mirror 12, a part of the light from the second objective lens 11 is emitted to the camera port 16 (see FIG. 2). Can do. In addition to the camera, the camera port 16 can be equipped with a photodetector (for example, a PMT). In addition, a photodetector can be attached to a port where the camera 70 is attached.

  The stage unit 20 includes a stage 21 on which the specimen 2 is placed, a revolver 23 that holds a plurality of objective lenses 22, and a revolver column 24 that holds the revolver 23 and moves up and down along the optical axis of the objective lens 22. Prepare. The stage 21 on which the specimen 2 is placed includes a sliding stage 25 on which the specimen 2 is placed and moved on the stage 21 in an arbitrary direction.

  The objective lens 22 used in the inverted microscope 1 is an infinity corrected optical objective lens. Thereby, the light from the specimen 2 collected by the objective lens 22 is emitted from the objective lens 22 toward the second objective lens 11 as parallel light. As a result, in the inverted microscope, a plurality of optical devices (the epi-fluorescence illumination device 50 and the laser fluorescence illumination device 60) can be disposed between the objective lens 22 and the second objective lens 11.

  The revolver column 24 rotates a focusing dial (not shown) arranged on the base 10, so that a pinion gear (not shown) provided on the shaft of the motor 14 is engaged with a rack gear provided on the lower portion of the revolver column 24. Accordingly, the revolver support 24 is moved up and down along the optical axis of the objective lens 22. Thereby, the objective lens 22 can be focused on the observation position of the sample 2. Further, the revolver support 24 is rotated by the motor 14 in response to an instruction from a microscope controller (not shown) or rotation of a focusing dial by an observer, and the revolver support 24 is set to the optical axis of the objective lens 22 via the rack and pinion gear. Move up and down along.

  The transmitted illumination support column 30 includes a vertical portion 31 provided on the stage unit 20 and a horizontal portion 32 extending horizontally from the upper end of the vertical portion 31 toward the observation unit 40.

  A lamp house 35 in which a transmissive light source 33 such as a halogen lamp, a lens 34, and the like are housed is provided on the upper rear surface of the vertical portion 31. Illumination light from the lamp house 35 is transmitted through the horizontal portion 32 and is reflected in the direction of the objective lens 22 by the mirror 36 disposed near the tip of the horizontal portion 32 on the observation unit 40 side. The illumination light reflected by the mirror 36 passes through the lens 37 and is condensed on the sample 2 by the condenser lens 39 disposed on the vertical portion 31 and the horizontal portion 32 via the attachment portion 38. The mounting portion 38 is provided with a knob 38a that moves the condenser lens 39 up and down along the optical axis of the objective lens 22 (see FIGS. 2 and 3).

  The observation unit 40 includes a binocular unit 41, and includes a mirror 42 that relays the light beam reflected by the mirror 13 of the base unit 10 to the binocular unit 41, and an eyepiece 43.

  The light from the sample 2 is collected by the objective lens 22 and transmitted to the eyepiece 43 through the second objective lens 11 and the mirrors 12, 13, and 42, and the sample image is observed by the observer.

  In the inverted microscope 1, the epifluorescence unit 50 disposed in the optical path between the revolver 23 and the second objective lens 11 includes a lamp house 51, an illumination light projector 52, and a plurality of filter cubes 53 and 54. A filter turret 55 is provided. The lamp house 51 stores a mercury lamp, a xenon lamp, or the like that can emit light having a wavelength from visible light to ultraviolet light. The filter cubes 53 and 54 house wavelength selection filters 53a and 54a for observing incident fluorescence, dichroic mirrors 53b and 54b, emission filters 53c and 54c, and the like. Note that epifluorescence observation using the epifluorescence unit 50 is well-known and will not be described in detail.

  In the inverted microscope 1, the laser fluorescent unit 60 disposed in the optical path between the revolver 23 and the second objective lens 11 is an optical fiber 61 that introduces laser light as excitation light from a laser light source device (not shown). And a laser illuminating light projector 62 and a filter turret 65 on which a plurality of filter cubes 63 and 64 are mounted. The filter cubes 63 and 64 house wavelength selection filters 63a and 64a for observing laser fluorescence, dichroic mirrors 63b and 64b, emission filters 63c and 64c, and the like. Note that laser fluorescence observation using the laser fluorescence unit 60 is known and will not be described in detail.

  The existing objective designed between the second objective lens 11 and the revolver 23 is not limited to the epi-fluorescence unit 50 and the laser fluorescence unit 60, and is designed to be disposed between the second objective lens 11 and the revolver 23. AF optical units (for example, an epi-illumination unit) can be arranged.

  Next, the AF optical device 80 according to the present embodiment will be described with reference to FIGS.

  As shown in FIGS. 1 to 4, the AF optical device 80 mounted on the inverted microscope 1 is an AF illumination optical unit disposed separately from the revolver 23 in the vicinity of the lower back surface of the base unit 10. 81, an AF detection optical unit 82, a relay optical unit 83 disposed inside the base unit 10, the stage unit 20 and the revolver 23 of the inverted microscope 1, and an optical axis of the objective lens 22 disposed inside the revolver 23. And a dichroic mirror 84. Note that the AF illumination optical unit 81 and the AF detection unit 82 which are a part of the AF optical device 80 are not limited to the above positions and are separated from the revolver 23 and can be a place where the relay optical unit 83 can relay AF light described later. You may arrange | position in any place of the inverted microscope 1. FIG. For example, the arrangement location may be the side surface of the stage unit 20 in the vicinity of the revolver 23.

  As shown in FIG. 4, the AF illumination optical unit 81 emits near-infrared light (hereinafter referred to as AF light) (for example, an infrared LED), a light source 81a, a condensing lens 81b, and a half of the luminous flux. A semicircular stop 81c, a convex lens 81d, a concave lens 81e that is an offset lens, a half mirror 81f, and a mirror 83a.

  As shown in FIG. 4, the AF detection optical unit 82 includes a photodetector 82a such as a line sensor, a convex lens 82b, a half mirror 81f, and a mirror 83a.

  Here, the half mirror 81 f is shared by the AF illumination optical unit 81 and the AF detection optical system 82. The mirror 83a is shared by the AF illumination optical unit 81, the AF detection optical system 82, and the relay optical unit 83. Note that the AF illumination optical unit 81 and the AF detection optical system 82 may be appropriately added with optical members other than the above optical members in the design.

  As shown in FIGS. 1 to 3, between the dichroic mirror 84 and the mirror 83 a arranged on the optical axis of the objective lens 22 inside the revolver 23, a plurality of other mirrors 83 b constituting the relay optical unit 83. , 83c. Needless to say, the number of the plurality of mirrors 83a, 83b, 83c constituting the relay optical unit 83 is not limited to the above-described three.

  As shown in FIG. 4, the AF light from the light source 81a is condensed on the semicircular diaphragm 81c by the condenser lens 81b, and ½ AF light is emitted from the semicircular diaphragm 81c. The AF light emitted from the semicircular diaphragm 81c is converted into parallel light by the convex lens 81d and the concave lens 81e, passes through the half mirror 81f, and is tilted by about 45 degrees with respect to the optical axis of the AF illumination optical unit 81. Is incident on.

  As shown in FIGS. 1 to 3, the AF light reflected by the mirror 83a is transmitted along the optical axis of the objective lens 22 and along the parallel optical axis (AF optical axis). The light is incident on a mirror 83b disposed at an angle of about 45 degrees with respect to the axis, and is incident on a mirror 83c disposed on a surface intersecting the optical axis of the objective lens 22. The optical axis between the mirror 83b and the mirror 83c is separated from the optical axis of the objective lens 22. Note that the surface intersecting the optical axis of the objective lens 22 is preferably orthogonal to the optical axis of the objective lens 22.

  By configuring so that both optical axes are separated, it is possible to configure the AF optical axis to be separated from the optical axis of the illumination light projector 52 and the optical axis of the laser illumination light projector 62. it can. As a result, interference between the AF optical axis, the optical axis of the illumination light projector 52, and the optical axis of the laser illumination light projector 62 can be avoided.

  The AF light reflected by the mirror 83 c is reflected by the dichroic mirror 84 toward the dichroic mirror 84 disposed on the optical axis of the objective lens 22, and is condensed on the sample 2 via the objective lens 22.

  In the AF optical device 80, the focusing position of the AF light in the objective lens 22 is set at the interface between the cell as the sample 2 and the cover glass on which the cell is placed. Here, the specimen is assumed to be a cell or the like. It is also possible to deflect the AF light by arranging an even number of mirrors between the mirrors 83a and 83b of the relay optical unit 83. At this time, it is desirable to have at least one AF optical axis along and parallel to the optical axis of the objective lens 22. Since the AF light is along the optical axis of the objective lens 22 and has a parallel optical axis, the specimen 2 is continuously irradiated with the AF light even when the revolver 23 (objective lens 22) moves up and down during the focusing operation. Can do.

  On the other hand, the AF light reflected at the interface between the cell and the cover glass is incident on a ½ region different from the AF light at the time of entering the objective lens 22 and is incident on and reflected by the dichroic mirror 84. 83c, 83b, and 83a are relayed and enter the half mirror 81f. The returning AF light incident on the half mirror 81f is incident on a region different from the half AF light at the time of emission. The AF light reflected from the half mirror 81f is imaged on the line sensor 82a by the convex lens 82b.

  As described above, the AF optical device 80 constitutes an AF illumination optical system by optical members from the light source 81a to the objective lens 22, and constitutes an AF detection optical system by optical members from the objective lens 22 to the line sensor 82a. . The optical members from the half mirror 81f to the objective lens 22 are shared by the AF illumination optical system and the AF detection optical system.

  When the focus position of the objective lens 22 with respect to the AF light is at the interface between the cell and the cover glass, the focusing position of the AF light in the line sensor 82a is in the center and is focused by a control unit (not shown). It is judged.

  On the other hand, when the focal position of the AF light deviates from the interface between the cell and the cover glass, the focusing position of the AF light in the line sensor 82a is shifted from the central portion. The control unit moves the revolver 23 up and down along the optical axis of the objective lens 22 via the motor 14 so as to return the condensing position to the central portion based on the shift amount and the shift direction of the AF light condensing position in the line sensor 82a. Moving. Moreover, a control part maintains a focus position by performing the said control continuously. At this time, the controller drives the motor 14 to move the revolver 23 up and down instantaneously in accordance with the shift of the in-focus position, so that the weight of the revolver 23 is desired to be light. The AF illumination optical unit 81 and the AF detection optical unit 82, which are part of the AF optical device 80, are arranged separately from the revolver 23 to satisfy this requirement.

  Further, in the AF optical device 80, when the offset amount of the concave lens 81e that is an offset lens is set to zero, the focus position of the AF light in the objective lens 22, and the imaging optics composed of the objective lens 22 and the second objective lens 11 are used. The focal position of the system matches.

  Further, the AF optical apparatus 80 gives an offset to the focus position of the AF light by moving the concave lens 81 e that is an offset lens along the optical axis of the AF illumination optical unit 81. The control unit detects the offset amount of the concave lens 81e, and gives the revolver 23 a movement amount corresponding to the offset amount via the motor 14, thereby focusing on the position shifted by a predetermined offset amount. Thereafter, the in-focus state is maintained at this position. At this time, the focal position of the AF light is at the interface between the cell and the cover glass, and the focal position of the imaging optical system described above is positioned inside the cell (specimen 2) shifted by the offset amount.

  As described above, the AF mechanism using the AF optical device 80 moves the concave lens 81e, which is an offset lens, along the optical axis, thereby positioning the focal point of the imaging optical system at an arbitrary position in the cell. It has a function that can. Note that an AF control method using the AF optical device 80 is known (see, for example, Japanese Patent Application Laid-Open No. 2004-70276), and detailed description thereof is omitted.

  As described above, the inverted microscope 1 having the AF optical device 80 includes the relay optical system 83 in which the AF light is along the optical axis of the objective lens 22 and includes a parallel optical axis. 81 and the AF detection optical unit 82 can be separately arranged at a different location from the revolver 23. As a result, the inverted microscope 1 can reduce the weight of the revolver 23 and perform a focusing operation and a focusing maintaining operation with a small inertia force. Further, the inverted microscope 1 can realize an agile focusing operation because the revolver 23 is light in weight.

  Further, in the inverted microscope 1 having the AF optical device 80, the AF optical device 80 does not occupy the space between the revolver 23 and the second objective lens 11 by configuring the AF optical device 80 via the revolver 23. A plurality of other optical devices (for example, various illumination units) can be used, and various microscope observations can be performed.

1 Inverted microscope 2 Specimen 10 Microscope base (base)
DESCRIPTION OF SYMBOLS 11 2nd objective lens 12, 13, 14 Mirror 15 Half mirror 20 Stage unit 21 Stage 22 Objective lens 23 Revolver 24 Revolver support | pillar 25 Sliding stage 30 Transmitting illumination support | pillar 31 Vertical part 32 Horizontal part 35 Lamphouse 39 Condenser lens 40 Observation unit 50 Epi-fluorescence unit 51 Lamp house 52 Illumination light projector 55 Filter turret 60 Laser fluorescence unit 61 Optical fiber 62 Laser light projector 65 Filter turret 70 Camera 80 AF optical device 81 AF illumination optical unit 82 AF detection optical unit 83 Relay optical 83a, 83b, 83c Mirror 84 Dichroic mirror

Claims (12)

A first mirror that is provided inside a revolver that holds the objective lens and that is disposed on the optical axis of the objective lens and reflects autofocus light;
An autofocus illumination optical system that irradiates the specimen with the autofocus light deflected by the first mirror via the objective lens;
An autofocus detection optical system for detecting the autofocus light from the specimen through the objective lens;
A relay optical system shared by at least a part of the autofocus illumination optical system and the autofocus detection optical system;
The autofocus light is shared by the illumination optical system and the detection optical system, the first mirror and the relay optical system,
The autofocus illumination optical system and the autofocus detection optical system are arranged on a microscope mirror base separated from the revolver,
The optical axis of the relay optical system and the optical axis of the objective lens are separated,
An autofocus device, wherein a focusing operation is performed by driving the objective lens held by the revolver along the optical axis of the objective lens.   A stage on which the specimen is placed is disposed between the specimen and the objective lens, and the autofocus illumination optical system and the autofocus detection optical system are disposed on a side closer to the objective lens. The autofocus device according to claim 1.   The objective lens includes a first objective lens that is driven for the focusing operation and a second objective lens that is not driven, and the autofocus illumination optical system and the autofocus detection optical system are the second objective lens. The autofocus device according to claim 1, wherein the autofocus device is disposed on a side closer to the lens.   The autofocus device according to claim 3, wherein a fluorescence unit for observing the specimen with fluorescence is disposed between the first objective lens and the second objective lens.   The autofocus device according to any one of claims 1 to 4, wherein the first mirror is a dichroic mirror.   6. The autofocus device according to claim 1, wherein at least a part of an optical axis of the relay optical system and an optical axis of the objective lens are parallel to each other.   The relay optical system includes a second mirror that deflects the autofocus light deflected by the first mirror, and a third mirror that deflects the autofocus light deflected by the second mirror. ,
  The autofocus device according to any one of claims 1 to 6, wherein an optical axis of at least a part of the autofocus light between the second mirror and the third mirror is parallel.   The autofocus device according to any one of claims 4 to 7, wherein a fluorescence unit for observing the specimen with fluorescence is disposed between the second mirror and the third mirror.   The autofocus illumination optical system includes a light source, a first condenser lens, a diaphragm, a collimator lens, an offset lens, and a half mirror in order along the optical axis of the autofocus illumination optical system. ,
  2. The autofocus detection optical system includes a photodetector, a second condenser lens, and the half mirror in order along the optical axis of the autofocus detection optical system. 9. The autofocus optical device according to any one of items 8.   10. The light source of the autofocus light is a light source that emits light having a wavelength different from the light for observing a specimen and different from the wavelength of excitation light in fluorescence observation. The autofocus optical device described.   The autofocus device according to any one of claims 1 to 10, wherein the autofocus light is collected at an interface between a specimen and glass.   A microscope comprising the autofocus optical device according to any one of claims 1 to 11.