JP2000321502A - Laser scanning microscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain confocal effect for improving the picture quality of a simple laser scanning microscope which has its Y-directional scan fixed (linear scan type) and picks up an image formed by an objective at a return destination directly by a television camera. SOLUTION: To obtain the confocal effect, a scan with return light which is made by a galvanomirror 23 is deflected back to obtain the undeflected luminous flux before the scan, which is made to be imaged linearly in a stationary state while including information on a material A; and a thin-gap slit 21 is placed at the position, its slit image is restored and imaged by a relay lens 22 and the galvanomirror 23, and picked up by a CCD camera 24, thereby an image with the confocal effect is obtained while maintaining the easiness of picking up the image directly by the television camera.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser scanning microscope in which transmitted light or reflected light from a material is received by a light receiving element of a television camera to capture an image.

[0002]

2. Description of the Related Art In general, a laser scanning microscope scans a document surface with a laser light spot focused to about 1 micron,
The light / dark information of each position (point) of the return light is received by a photoelectric conversion sensor, and the electrically converted light / dark information is accumulated and observed on an enlarged screen of a monitor television.
This means that only individual positions are always illuminated, unnecessary and harmful light is not mixed, and defocused light is received at a conjugate position with the data surface through a pinhole of the same size as the data surface scanning spot light. And harmful light can be excluded. For this reason, compared with a conventional optical microscope, even if the same objective lens is used, a high resolution and a high contrast can be obtained, which is called a confocal method.

[0003] Laser scanning microscopes include a reflection type which captures a reflected light image from a material and a transmission type which captures a transmitted light image. In both cases, the material is scanned in both X and Y directions by a laser spot light, and each point is scanned. Pixels are recorded with light and dark information, and these are arranged in a plane to form a screen, and the electronic equipment for that is complicated, and because it is a dedicated machine for small-scale production, it must be expensive. There was a problem.

In order to solve such a problem and make it cheap and easily available, the present inventor has proposed an apparatus shown in FIG. 2 as an apparatus which can easily take an image using an ordinary television camera. developed.

In this apparatus, a light beam from the linearly polarized laser 1 is formed into a fixed light beam in the entire scanning area in the Y direction by using a cylindrical lens 4 (in the image forming plane, the light beam becomes a line in the Y direction.
Line scanning).

Scanning is performed in the X direction by the carbano mirror 5, an image is formed at the pupil position B by the relay lens 6, bent by the polarizing beam splitter 3, and condensed and formed on the surface of the document A by the objective lens 8. That is, A and B are in a conjugate relationship.

After transmitting the data, the light passes through the λλ wavelength plate 11 by the transmission side objective lens 10 and forms an image at a position conjugate with A. A concave mirror 12 having the image chief ray at its position having a radius of curvature.
, The optical path returns exactly the same, and 1 / 4λ
The wave plate 11, the transmission-side objective lens 10, the document 9, and the irradiation-side objective lens 8 return to reach the polarization beam splitter 3.

Since the return light passes through the quarter-wave plate 11 twice, the direction of the polarization plane is 90 ^. The return light flux is transmitted through the polarization beam splitter 3 without being bent, and forms an image at a conjugate position with the material A. CCD at that position
The camera 24 was placed.

[0009] Since there is no pinhole at the time of light reception, it is a non-confocal type. In the text, it is called a simplified laser scanning microscope.

[0010]

The conventional apparatus as described above has a simple optical system, and an apparatus for imaging can be provided at a low cost because a readily available television camera can be used. However, there is a problem that the sharpness of the image is slightly reduced as compared with the conventional confocal type.

The present invention has been made in view of such conventional problems, and has been made to provide a device capable of obtaining a clearer image in the simple device described above.

[0012]

In order to solve the above-mentioned conventional problems, in the above-mentioned simplified laser scanning microscope, in order to obtain a confocal effect, the scanning of the returning light by the carbano mirror is turned back, and The image is returned to a light beam that does not fluctuate, and an image is formed in a stationary line shape including the information of the material A.

A slit is placed at that position, the slit plane image is restored by a relay lens and a galvanomirror to form an image, and the image is projected on a television camera. As a result, an image having a confocal effect was obtained.

[0014]

Embodiments of the present invention will now be described with reference to the drawings.

In FIG. 1, 1 is a polarizing laser, 2 is a reflecting mirror, 3 is a polarizing beam splitter, 4 is a cylindrical lens, 5 is a galvano mirror, 6 is a relay lens, 7 is a reflecting mirror, 8 is an irradiation side objective lens, Reference numeral 9 denotes a reference table, 10 denotes a transmission side objective lens, 11 denotes a １ ／ λ wavelength plate, 12 denotes a concave mirror, 20 denotes a cylindrical lens, 21 denotes a slit,
2 is a relay lens, 23 is a galvanometer mirror, 24 is CC
D camera.

In this laser scanning microscope, the polarization beam splitter 3 of the simplified laser scanning microscope of FIG. 2 is replaced with a mirror 7, and a cylindrical lens 4 and a reflecting mirror 2 are provided.
A polarizing beam splitter 3 is placed between (FIG. 1)
In the bent optical path, a cylindrical lens 20, a slit 21, a relay lens 22, a galvanomirror 23, a CCD
The arrangement of the camera 24 is changed and additionally arranged.

As in the case of the simplified laser scanning microscope, the return light passes through the objective lens 8. The mirror 7 returns along the same optical path as the outward path, passes through the relay lens 6, and is returned by the galvanomirror 5 to reverse the scanning in the X direction, thereby forming a fixed light flux.

Further, after passing through the cylindrical lens 4, it becomes a parallel light beam containing information of the material A in the Y direction in a laminated manner. Since there is the modified beam splitter 3 here, the return light is bent differently from the outward path.

The cylindrical lens 20 converges light in the X direction, and a linear still image in the Y direction is formed at the position of the slit 21. Here, the information of the material A is arranged in the Y direction.

A slit 21 is placed here, and the slit image is formed by a relay lens 22 and a galvanometer mirror 23 by a CCD.
An image is formed according to the screen size of the camera.

When the shutter 30 and the wave plate 31 indicated by the dotted lines in FIG. 1 are put in the optical path, return light reflected on the data surface A is obtained, and it is possible to use a reflection type.

[0022]

As described above, in the present invention, material A
Is formed in a thin line at the position of the slit 21, and information in the Y direction at the position in the X direction scanning is tightly stacked in the thin line. Placing a slit here has the same effect as placing a confocal pinhole. Then, the slit surface image is restored by the relay lens 22 and the galvanomirror 23 to form an image on the CCD camera.

As described above, the confocal effect can be obtained without losing the convenience of direct imaging on the CCD camera.

[Brief description of the drawings]

FIG. 1 is an optical path diagram showing a configuration of an example of a laser scanning microscope according to the present invention.

FIG. 2 is an optical path diagram showing a configuration of a conventional laser scanning microscope.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Polarized laser 2 Reflecting mirror 3 Polarizing beam splitter 4 Cylindrical lens 5 Galvano mirror 6 Relay lens 7 Reflecting mirror 8 Irradiation side objective lens 9 Reference table 10 Transmission side objective lens 11 Wave plate 12 Concave mirror 20 Cylindrical lens 21 Slit 22 Relay lens 23 Galvano Mirror 24 CCD camera 30 Shutter 31 Wave plate A Material B Pupil position

Claims (1)

[Claims] 1. A laser scanning microscope in which Y-direction scanning is of a fixed type (line scanning type) and an image of return light formed by an objective lens is directly projected on a television camera. The X-scan is turned back in, a stationary linear image is formed using a cylindrical lens, a slit is placed at the image forming position of the linear image, and the slit plane image is relayed by a relay lens.
A laser scanning microscope characterized in that it is restored to an image using a galvanomirror and then copied to a TV camera.