JP3082183B2 - Confocal microscope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a confocal microscope using a fine aperture (hereinafter, also referred to as a pinhole array) having a plurality of fine apertures (for example, pinholes), and more particularly to a confocal microscope combined with a confocal optical scanner. The present invention relates to an improvement for improving light use efficiency and resolution in a peripheral portion of a visual field in a microscope of a finite optical system.

[0002]

2. Description of the Related Art FIG. 4 shows an example of a main part of an optical system when an optical scanner is mounted on a conventional finite microscope. In the figure, 10 is an optical scanner, and 30 is an objective lens. Although the details of the optical scanner 10 will be described later, the laser light focused by the microlens ML in the optical scanner is a pinhole P.
H indicates a point light source (in the figure, a point light source having three pinholes is representatively shown), and light from the point light source enters the objective lens 30.

An optical scanner in which a plurality of minute openings having a plurality of minute openings are rotatably incorporated is disclosed in, for example, US Pat. No. 3,926,500 and US Pat.
7,254, U.S. Pat. No. 5,067,805, and the like. FIG. 6 shows an example of an optical scanner in which a microlens is further added to this type of optical scanner. Japanese Patent Application No. 4-15411 (Japanese Patent Application Laid-Open No. 5-60980) filed by the applicant of the present invention discloses an optical scanner for confocal use. ] Is shown. The confocal optical scanner includes a disk unit 11, a beam splitter 12, and a motor 13 that rotates the disk unit 11 at a constant speed.

In the disk unit 11, a plurality of Fresnel lenses (corresponding to microlenses ML in FIG. 4) formed on one surface of a glass substrate 141 shown in FIG. and _r only sequentially staggered condensing disc 14 which is formed, shifted sequentially by (Pshita circumferentially) P _r in a plurality of the pinhole PH formed in the substrate 151 in the radial direction as shown in (b) of FIG. 7 The pinhole disk 15 formed by the
And a drum 16 which connects the pinhole disk 15 so that the pinhole PH is arranged at the focal position of the Fresnel lens. The beam splitter 12 is held between the condenser disk 14 and the pinhole disk 15 by means not shown.

The configuration shown in FIG. 6 is an example of a configuration in which the confocal optical scanner 10 is attached to a microscope of a finite optical system. The laser light emitted from the confocal optical scanner is focused by the objective lens 41 and is irradiated on the sample 42. The light returned from the sample 42 passes through the objective lens 41 again and is focused on the pinhole PH of the confocal optical scanner 10, where an actual image of the sample surface is obtained. The light passing through the pinhole PH is reflected by the beam splitter 12, passes through the condenser lens 43, and is irradiated on the image receiving surface of the camera 44. By driving the motor 13 to rotate the disk unit 11, the sample 42
Is optically scanned, and an image of the sample surface can be observed with a camera.

[0006]

In the finite optical system microscope shown in FIG. 4, the distance between the pinhole PH and the objective lens 30 is the rear focal length a of the objective lens. Therefore, all the light from the pinhole PH is incident on the objective lens 30 at an angle of 0 ° with the optical axes parallel to each other, and the peripheral light is shifted to a position shifted from the pupil center of the objective lens 30 as shown in FIG. Incident. This causes the following problem.

(1) Depending on the type of the objective lens 30, the pupil diameter is small, the amount of light from the peripheral pinhole is reduced, and the amount of illumination decreases in the periphery (illumination unevenness). (2) The light from the peripheral pinhole cannot sufficiently fill the pupil of the objective lens, and the numerical aperture (NA) of the objective lens 30 cannot be used. (3) The return light (reflected light or fluorescent light) from the sample is obliquely incident on the pinhole PH, and the transmission efficiency is reduced. .

In view of the foregoing, an object of the present invention is to dispose a lens having the same focal length as the back focal length of the objective lens between the minute aperture and the objective lens so that the lens is located at the center of the pupil of the objective lens. Light from the small aperture of the
An object of the present invention is to provide a confocal microscope capable of eliminating light amount loss in a peripheral portion, increasing light use efficiency, and increasing resolution in a peripheral portion.

[0009]

In order to achieve the above object, according to the present invention, a confocal optical scanner having a plurality of minute openings having a plurality of minute openings is attached to a microscope of a finite optical system, and The sample is irradiated with laser light through the objective lens, and the return light from the sample is configured to return to the minute opening through the objective lens. The minute opening is rotated to optically scan the sample surface to form an image of the sample surface. A confocal microscope configured to enable observation, wherein the micro-aperture and the front
Placed between the objective lenses and behind the objective lens
A relay for forming an image plane of the minute aperture at a position of a focal length
A lens having a focal length behind the objective lens;
Located at the image plane position of the minute aperture by the relay lens
Lens, and all the light from the minute aperture
It is designed to enter the center of the pupil of an object lens.
You.

[0010]

In a configuration in which an optical scanner is combined with a microscope of a finite optical system, a lens having a focal length equal to the focal length behind the objective lens is arranged between the pinhole array and the objective lens. As a result, light from the pinholes at the peripheral portion also enters the center of the pupil of the objective lens, so that there is no loss of light amount at the peripheral portion and the resolution of the peripheral portion is improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a main part configuration diagram showing one embodiment of a confocal microscope according to the present invention. The same parts as those in FIG. 3 are denoted by the same reference numerals, and the description of those parts will be omitted. FIG. 1 differs from FIG. 4 in that a field lens 60 is arranged immediately below a pinhole array.

The field lens 60 has the same focal length as the rear focal length a of the objective lens 30 of the finite microscope,
It is arranged close to the pinhole array 11 (in other words, directly below the pinhole array 11). The laser light is focused on the pinhole PH by the microlens ML, and the laser light passing through the pinhole PH is bent by the field lens 60 disposed immediately below to the center of the pupil of the objective lens 30. Therefore, the laser beams from all the pinholes PH enter the pupil center of the objective lens 30 as shown in FIG.

The optical axis of the return light from the sample (not shown) is bent by the field lens 60 so that it enters the pinhole PH at 0 degree. Thereby, the light use efficiency of the signal light increases. The field lens 60 causes aberrations and the like when it is far away from the pinhole PH surface. However, since the focal length a can be designed to be generally 200 mm and the distance between the pinhole PH and the field lens 60 can be designed to be about 10 mm, the aberration is a practical problem. do not become.

FIG. 3 is a block diagram showing another embodiment of the present invention. In the figure, 71 is a relay lens, and 72 is a lens. The relay lens 71 is a lens that forms an image plane of the pinhole PH at the position of the focal length a on the rear side of the objective lens 30, and is disposed between the pinhole PH and the objective lens 30. The lens 72 has the same focal length as the rear focal length a of the objective lens 30, and is arranged at the position of the image plane of the pinhole formed by the relay lens 71. According to such a configuration, all the light from the pinhole enters the center of the pupil of the objective lens 30.

The present invention is not limited to the above embodiment, but can be appropriately modified and modified. For example, the micro lens ML may not be provided. Further, the shape of the minute opening is not limited to a circle like a pinhole. Other shapes can be used as long as the same purpose can be achieved.

[0016]

As described above, according to the present invention, since the laser beam from the small aperture in the peripheral portion can be incident on the center of the pupil of the objective lens, the following effects can be obtained, which is extremely useful. (1) Due to the pupil diameter of the objective lens, the amount of light from the minute opening in the peripheral portion is not reduced, the loss of the amount of light is eliminated, the light use efficiency is improved, and illumination unevenness does not occur. (2) The pupil of the objective lens can be effectively used for the small aperture in the peripheral portion as well as the small aperture in the central portion, and the numerical aperture does not decrease, and the resolution only in the peripheral portion does not decrease. (3) In the configuration shown in FIG.
Thus, the light can be made to be incident at 0 degree to the minute aperture, the transmission efficiency of the minute aperture can be increased, the influence of blurring and aberration in the optical system can be reduced, the peripheral image can be bright, and the resolution can be increased.

[Brief description of the drawings]

FIG. 1 is a main part configuration diagram showing an embodiment of a confocal microscope according to the present invention.

FIG. 2 is a diagram showing a relationship between a pupil of an objective lens and a laser beam incident position.

FIG. 3 is a main part configuration diagram showing another embodiment of a confocal microscope according to the present invention.

FIG. 4 is a main part configuration diagram when an optical scanner is attached to a conventional finite optical system microscope.

FIG. 5 is a diagram showing a relationship between a pupil of an objective lens and a laser beam incident position in FIG.

FIG. 6 is a configuration diagram showing an example of a confocal optical scanner.

FIG. 7 is a diagram illustrating details of a light-collecting disk and a pinhole disk shown in FIG. 6;

[Explanation of symbols]

 10 Optical Scanner 30 Objective Lens 60 Field Lens 71 Relay Lens 72 Lens PH Pinhole

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-104187 (JP, A) JP-A-7-128595 (JP, A) JP-A-4-330412 (JP, A) JP-A-7-104 199074 (JP, A) Japanese Utility Model Hei 4-89906 (JP, U) Special Table Hei 5-508235 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02B 21/00-21 / 36

Claims (1)

(57) [Claims] A confocal optical scanner having a fine aperture having a plurality of fine apertures is attached to a microscope of a finite optical system, and a laser beam from the fine aperture is irradiated on the sample through an objective lens. wherein configured to return to the microscopic aperture through an objective lens, the fine opening the sample surface by rotating the a confocal microscope configured to observe the image of the light scanned sample surface, the fine opening And between the objective lens,
The image of the micro aperture at the position of the back focal length of the objective lens
A relay lens forming a surface, and the relay lens having a focal length behind the objective lens.
Lens at the position of the image plane of the minute aperture
And all light from the minute aperture is in the pupil of the objective lens.
Confocal microscope characterized by being incident on the heart
mirror.