JP3358647B2 - Confocal light scanner - 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 optical scanner which performs optical scanning by rotating a disk provided with a plurality of condensing means and apertures, and more particularly to a confocal optical scanner which is bright and can be operated at high speed. About.

[0002]

2. Description of the Related Art A confocal optical scanner performs optical scanning by rotating two disks provided with a plurality of condensing means and apertures.

FIG. 6 is a block diagram showing an example of such a conventional confocal optical scanner, which is disclosed in Japanese Patent Application No. 4-15411 (Japanese Unexamined Patent Application Publication No. 5-60980) filed by the present applicant.
Gazette).

In FIG. 6, reference numeral 1 denotes a laser, 2 denotes a disk provided with a microlens as a condensing means (hereinafter, referred to as a microlens plate), 3 denotes a beam splitter as a light splitting means, and 4 denotes an aperture. A disk provided with a pinhole (hereinafter referred to as a pinhole plate), 5 is an objective lens, 6
Denotes a sample, 7 denotes a relay lens, 8 denotes a light receiver, 9 denotes a motor that rotates the microlens plate 2 and the pinhole plate 4 in synchronization.

The output light of the laser 1 is incident on the microlens plate 2 and is condensed on each pinhole on the pinhole plate 4 via the beam splitter 3 by each microlens provided on the microlens plate 2. You. The light passing through each pinhole on the pinhole plate 4 is
And is incident on the sample 6 through.

Return light such as reflected light from the sample 6 is again incident on the pinhole plate 4 via the objective lens 5, and light passing through each pinhole on the pinhole plate 4 is reflected by the beam splitter 3. , A light receiver 8 via a relay lens 7
Is incident on.

The microlens plate 2 and the pinhole plate 4 are fixed on the same shaft, and are rotated synchronously by a motor 9 mounted on this shaft.

Here, the operation of the conventional example shown in FIG. 6 will be described. The output light of the laser 1 scans the surface of the sample 6 by passing through each microlens on the microlens plate 2 and each pinhole on the pinhole plate 4 which rotate synchronously. Then, the reflected light from the sample 6 is received by the light receiver 8 to obtain a confocal image.

Further, as described above, each microlens provided on the microlens plate 2 condenses incident light to each pinhole on the pinhole plate 4 via the beam splitter 3. That is, by arranging the pinhole at the focal position of the microlens, it is possible to improve the utilization efficiency of the incident light from the laser 1.

[0010]

However, in the conventional pinhole plate 4 shown in FIG. 6, the efficiency of available light is low due to the relationship between the pinhole diameter and the pinhole pitch.

For example, FIG. 7 is a plan view showing a part of the pinhole of the pinhole plate 4, and "a" and "b" in FIG.
The ratio between the pinhole diameter and the pinhole pitch shown in FIG.
If 0, the area of the light irradiated on the sample 6 is only about 1% of the entire surface of the sample 6.

In this case, it is sufficient to increase the intensity of the excitation light. However, depending on the type of the sample, the sample is easily discolored. Therefore, if the intensity of the excitation light cannot be increased, the amount of light received by the light receiver 8 cannot be improved. .

For this reason, there is a method of scanning with slit light using a mirror scan and an acousto-optic device. FIG. 8 is a configuration diagram showing an example of such a conventional optical scanning device.

In FIG. 8, reference numeral 100 denotes a laser beam, 10 denotes a cylindrical lens, 11 denotes a lens, and 12 denotes a mirror. The laser light 100 is focused on a lens 11 by a cylindrical lens 10 and is incident on a mirror 12. The mirror 12 is driven by means (not shown) as shown by "A" in FIG.

As a result, the slit light scans the sample surface and the like as shown by "b" in FIG. However, in this case, there is a problem that the efficiency of available light is low because only one slit light is scanned. Therefore, an object of the present invention is to improve the efficiency of available light and realize a confocal optical scanner capable of high-speed scanning.

[0016]

According to a first aspect of the present invention, there is provided a disk having a plurality of light collecting means and a plurality of apertures having the same pattern as the light collecting means. In a confocal optical scanner for scanning a sample by condensing light passing through the condensing means and the aperture by rotating a disc synchronously, a disc provided with a slit as the aperture, A confocal optical scanner, comprising: as a light means, a disk on which a cylindrical microlens having the same shape as the slit is formed.

In order to achieve the above object, a second aspect of the present invention is characterized in that, in the first aspect of the present invention, the shapes of the slit and the cylindrical microlens are helical. .

According to a third aspect of the present invention, there is provided the first aspect of the present invention, wherein the slits and the cylindrical microlenses are radial in shape.

In order to achieve the above object, a fourth aspect of the present invention is characterized in that, in the first to third aspects of the present invention, non-coherent light is used as a light source.

In order to achieve the above object, a fifth aspect of the present invention is characterized in that in the first, second and fourth aspects of the present invention, the interval between the slits is constant. .

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a configuration diagram showing one embodiment of a confocal optical scanner according to the present invention.

In FIG. 1, reference numeral 13 denotes a disk in which cylindrical microlenses are spirally formed (hereinafter, referred to as a cylindrical microlens plate), 14 denotes a beam splitter, and 15 denotes an aperture for opening the cylindrical microlens. A disk provided with slits of the same shape (hereinafter, referred to as a slit plate), 16 is an objective lens, 17 is a sample, 18 is a lens, 19 is a light receiver, and 101 is illumination light.

The illumination light 101 is incident on the cylindrical microlens plate 13 and is collected by the respective cylindrical microlenses provided on the cylindrical microlens plate 13 via the beam splitter 14 into the respective slits on the slit plate 15. Be lighted. Slit plate 1
The light passing through each slit on 5 is incident on the sample 17 via the objective lens 16.

Return light such as reflected light from the sample 17 is again incident on the slit plate 15 via the objective lens 16, and light passing through each slit on the slit plate 15 is reflected by the beam splitter 14, Receiver 1 via
9 is incident.

The cylindrical microlens plate 13 and the slit plate 15 are fixed on the same shaft, and are rotated synchronously by a motor (not shown) mounted on this shaft.

The operation of the embodiment shown in FIG. 1 will now be described with reference to FIG. FIG. 2 is a plan view showing an example of the cylindrical microlens plate 13. Irradiation light 101 condensed by a spiral lens as shown by "a" in FIG.
Passes through a helical slit of the same shape formed on the slit plate 15 and returns as reflected light.

The reflected light that is not reflected from the focal plane of the objective lens 16 and spreads in the "b" direction in FIG. 2 is blocked by the slit plate 15, so that the confocal effect in the "b" direction in FIG. Will occur.

For example, FIG. 3 is a plan view showing a part of the slit of the slit plate 15, and "a" and "b" in FIG.
The ratio between the slit width and the slit pitch shown in b) is 1: 1.
If it is 0, the area of the light applied to the sample 17 is ten times as large as that of the conventional example.

Although only one slit light can be used in an optical scanning device using a mirror scan or an acousto-optical element, since a plurality of slits are formed in the slit plate 15, And the efficiency of the available light can be improved 10 to 100 times as compared with the optical scanning device.

FIG. 4 is a plan view showing the relationship between the visual field and the slit. In FIG. 4, "a" indicates the slit and "b" indicates the visual field.

Here, if the linear velocity of the slit light of the optical scanning device is the same as the linear velocity of the present invention, the distance to be scanned is "C" in FIG. The time required to scan the entire field of view shown in FIG.

As a result, by using the cylindrical microlens plate 13 and the slit plate 15 as the scanning means, the efficiency of available light can be improved and high-speed scanning can be performed.

It should be noted that Japanese Patent Application No. Hei.
Similarly to the phenomenon described in JP-A-149320 (JP-A-5-341191), when the pattern of the cylindrical microlens plate 13 and the slit plate 15 and the rotation axis are eccentric, scan fringes occur.

In this case, it can be improved by replacing the slit as shown in FIG. As can be seen from FIG. 5, the slits are radial.

Laser light is often used as a light source for a confocal microscope, but if a slit as shown in FIG. 2 is used, speckle noise may be generated in a direction perpendicular to "b" in FIG. .

Therefore, the use of output light of a halogen lamp or a xenon lamp, or non-coherent light such as laser light with a high frequency superimposed thereon as the irradiation light 101 makes it possible to prevent the speckle noise.

When the interval between the slits on the outer peripheral side is increased, the outer peripheral portion becomes dark. Therefore, Japanese Unexamined Patent Publication No.
As shown in Japanese Patent No. 127090, by making the interval between the slits always constant, the outer peripheral portion does not become dark.

[0038]

As is apparent from the above description,
According to the present invention, the following effects can be obtained. By using a cylindrical microlens plate and a slit plate as the scanning means, the efficiency of available light can be improved and a confocal optical scanner capable of high-speed scanning can be realized.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of a confocal optical scanner according to the present invention.

FIG. 2 is a plan view showing a cylindrical microlens plate.

FIG. 3 is a plan view showing a part of a slit of a slit plate.

FIG. 4 is a plan view showing a relationship between a visual field and a slit.

FIG. 5 is a plan view showing slits in which scan fringes caused by eccentricity are improved.

FIG. 6 is a configuration block diagram illustrating an example of a conventional confocal optical scanner.

FIG. 7 is a plan view showing a part of a pinhole of a pinhole plate.

FIG. 8 is a configuration diagram illustrating an example of a conventional optical scanning device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 laser 2 microlens plate 3, 14 beam splitter 4 pinhole plate 5, 16 objective lens 6, 17 sample 7 relay lens 8, 19 light receiver 9 motor 10 cylindrical lens 11, 18 lens 12 mirror 13 cylindrical microlens plate 15 Slit plate 100 Laser light 101 Illumination light

Claims (5)

(57) [Claims] 1. A disk having a plurality of light-collecting means and a disk having a plurality of apertures having the same pattern as the light-collecting means are rotated in synchronization with each other, so that light passing through the light-collecting means and the light-opening is rotated. In a confocal optical scanner that condenses and scans a sample, a disc provided with a slit as the opening, a disc formed with a cylindrical microlens having the same shape as the slit as the condensing means, A confocal optical scanner comprising: 2. The confocal optical scanner according to claim 1, wherein said slits and said cylindrical microlenses have a spiral shape. 3. The confocal optical scanner according to claim 1, wherein said slits and said cylindrical microlenses have radial shapes. 4. The confocal optical scanner according to claim 1, wherein non-coherent light is used as a light source. 5. The confocal optical scanner according to claim 1, wherein an interval between said slits is constant.