JPH075367A - Infrared microscope - Google Patents

Abstract

PURPOSE:To simplify structure, to simultaneously observe entire visual field and the position of a masking aperture, and to reduce the deterioration of an image by synthesizing the image of a sample which does not pass through the aperture and the image of the aperture to be in the same positional relation as in the case of infrared measurement. CONSTITUTION:The image of the sample S is formed at the position of the aperture 2 by an objective optical system 5, and in the case of measurement by visual observation, simultaneously, the image is also formed on an image surface I by a half mirror 3 arranged halfway and transmitted to an optical system 7 for visual observation. The image of the aperture 2 is superposed on the image of the sample S so as to be observed in the optical system 7. Since illumination for the aperture 2 is independent of illumination for a sample in the optical system 7, the color of the illumination for the aperture is changed by interposing a filter, or the image of the aperture may be colored by coloring the edge or the whole of the aperture 2 and the back of a mirror 4. Then, the synthetic image is easily changed in accordance with the kind of the sample S, and the image of the aperture is easily discriminated from the image of the sample.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared microscope used for identifying minute foreign matters.

[0002]

2. Description of the Related Art A general structure of a microscopic infrared measuring device is shown in FIG. The infrared light from the interferometer is switched between a transmission illumination optical system and a reflection illumination optical system by a transmission / reflection switching mirror 80 depending on whether it is a transmission measurement or a reflection measurement, and is condensed by a condenser 6 or an objective optical system 5. And illuminate the sample. The infrared light transmitted (reflected) through the sample is collected by the objective optical system 5 and guided to the MTC detector 85. In analysis, the analysis region in the sample is determined while observing the sample image with visible light. When performing analysis, in order to prevent light outside the analysis region from entering the measurement system, it is necessary to use the variable masking aperture 1 for masking according to the size of the analysis region. Since the part masked by is not visible, it is difficult to match the size of the aperture with the analysis region, and there is a problem that the aperture enters the analysis region, that is, the aperture is set too narrow. Therefore, there is also a proposal that it is possible to see the entire field of view and the aperture at the same time by dividing the optical path in front of the masking aperture and combining the light that passed through the aperture and the light that does not pass through it again. In this method, since the image of the sample masked by the aperture and the image not masked by the aperture are superimposed, the optical path becomes complicated,
At the part of the sample to be measured (the part that is not masked), the same two images will be superimposed, so the image of the part to be measured will be significantly deteriorated by a slight deviation of the optical axis, which is inconvenient for visual observation. There was a problem that

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an infrared microscope having a simple structure, capable of simultaneously observing the entire field of view and the position of the masking aperture, and having little image deterioration.

[0004]

In an infrared microscope, an aperture having an opening on the measurement optical axis, a visible light source for irradiation of the aperture provided on the measurement optical axis so that the aperture can freely move in and out, the aperture and the objective. A half mirror that is installed diagonally between the optical system and the measurement optical axis, a concave mirror that is provided outside the measurement optical axis, and a visible observation that is provided on the opposite side of the measurement optical axis from the concave mirror. It has an optical system, and the visible image of the aperture is formed on the optical axis of the visible observation optical system by the concave mirror, and the microscope image of the sample and the image of the aperture that do not pass through the aperture are the optical axis of the visible observation optical system. They were formed on top of each other, and they were combined so as to have the same positional relationship as during infrared measurement, and the size of the aperture could be adjusted while observing the image of the part masked by the aperture.

[0005]

[Function] By combining the image of the sample that does not pass through the aperture and the image of only the aperture with a half mirror so that they can be seen at the same time, the duality of the sample image is eliminated and the aperture is mixed in the sample image. You can now see the area you are in. Moreover, since the image of the aperture and the image of the sample are independent, the color and amount of illumination light for the aperture, the irradiation location, the edge of the aperture and the whole, and the filter can be used. The composite image for observation can be easily changed according to the type of sample so that the portion to be measured can be seen most clearly.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a layout diagram of an optical system for visible observation in a transmission measurement mode according to an embodiment of the present invention. Figure 1
In the figure, S is a sample, 1 is a visible light source for irradiating visible light, and irradiates the variable masking aperture 2. This aperture 2 is placed at the position of the sample image on the optical axis of the measurement optical system. Variable masking aperture 2
Can change the size of the opening. Reference numeral 3 is a half mirror, and 4 is a concave mirror, and the center of curvature thereof is located at a position symmetrical to the center of the aperture of the variable masking aperture 2 and the mirror surface of the half mirror 3 (position of image plane I), and illuminated by the light source 8. The image of the variable masking aperture 2
An image is formed on the image plane I and sent to the visible observation optical system 7. A condenser 6 condenses light from a light source (not shown) on the sample S. An objective optical system 5 forms an image of the sample S at the position of the aperture 2, and at the same time, at the time of visible observation measurement, the half mirror 3 disposed in the middle causes an image plane I
Is also imaged and sent to the visible observation optical system 7, and in the visible observation optical system 7, the aperture 2 image and the sample S image can be superimposed and observed. The half mirror 3 is movable, and is moved in and out along the optical axis as needed. In the visible observation optical system 7, it is better to illuminate the aperture image so as to be more discriminated from the sample image. However, since the illumination of the aperture 2 is independent of the sample illumination, a filter is used to intervene for the aperture. The aperture image may be colored by changing the color of illumination, coloring the edge or the whole of the aperture, or the back of the mirror 4, and the composite image can be easily changed according to the type of sample. It becomes easy to distinguish from the sample image.

FIG. 2 is an optical system layout diagram during measurement in the transmission measurement mode. The visible light source 1 is retracted from the optical axis, the infrared detection optical system 8 is advanced to the mark, and the half mirror 3 is moved. The sample image is removed from the optical axis so that the sample image is introduced into the infrared detection optical system 8. Infrared light is emitted from a lower light source (not shown) and is condensed on the sample S by the condenser 6,
The light transmitted through the sample, that is, the sample transmission image is imaged by the objective optical system 5 on the objective image plane where the aperture 2 is arranged, and after the field of view is limited by the aperture 2, it is guided to the infrared detection optical system 8. .

When switching between measurement and visible observation, as described above, instead of changing the positions of the light source 1 for visible observation and the optical system 8 for infrared detection, as shown in FIG. The total reflection mirror 9 may be moved in and out at an inclination of 45 ° on the optical axis of. Although the above description was given only in the case of the transmission measurement, as shown in FIG. 3, the half mirror 10 for introducing the sample illumination light during the reflection measurement is inserted between the objective optical system 5 and the half mirror 3. Thereby, the sample illumination light is condensed on the sample S by the objective optical system 5, and the reflected light from the sample S is passed through the objective optical system 5 and the half mirror 10,
The above-mentioned place can be observed and measured in the same manner.

[0009]

EFFECTS OF THE INVENTION According to the present invention, the image of the sample that does not pass through the aperture and the image of the aperture are synthesized so as to have the same positional relationship as in the infrared measurement, so that the maxin guar aperture can be adjusted to the size of the sample. It is easy to match and to know the position of the measurement part with respect to the entire visual field.
Moreover, the structure is simple, and the image of the sample is not deteriorated by a slight deviation of the optical axis. Furthermore, by using a filter or the like, the image of the sample and the image of the aperture can be changed independently, and a combined image that is most observable can be obtained for each sample.

[Brief description of drawings]

FIG. 1 is a layout diagram of an optical system in a transmission observation mode according to an embodiment of the present invention.

FIG. 2 is a layout diagram of an optical system in a transmission measurement mode according to an embodiment of the present invention.

FIG. 3 is a block diagram of a conventional example

[Explanation of symbols]

 S Sample I Image plane 1 Visual observation light source 2 Variable maxine aperture 3 Half mirror 4 Spherical mirror 5 Objective optical system 6 Condenser optical system 7 Visible observation optical system

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[Procedure amendment]

[Submission date] November 9, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a layout diagram of an optical system in a transmission observation mode according to an embodiment of the present invention.

FIG. 2 is a layout diagram of an optical system in a transmission measurement mode according to an embodiment of the present invention.

FIG. 3 is a layout view of an optical system according to another embodiment of the present invention.

FIG. 4 is a block diagram of a conventional example

[Explanation of Codes] S Sample I Image plane 1 Light source for visible observation 2 Variable maxine aperture 3 Half mirror 4 Spherical mirror 5 Objective optical system 6 Condenser optical system 7 Visible observation optical system

Claims (1)

[Claims] 1. An aperture having an opening on the measurement optical axis, a visible light source for irradiation of the aperture provided on the measurement optical axis so as to be able to move in and out, and a measurement optical axis between the aperture and the objective optical system. It has a half mirror that can be slanted in and out above, a concave mirror that is provided outside the measurement optical axis, and a visible observation optical system that is provided on the opposite side of the measurement optical axis from the concave mirror. A visible image of the aperture is formed on the optical axis of the visible observation optical system, and a microscope image of the sample that does not pass through the aperture and an image of the aperture are formed on the optical axis of the visible observation optical system. An infrared microscope characterized in that the size of the aperture can be adjusted while observing the image of the part masked by the aperture, which was synthesized so as to have the same positional relationship as during external measurement.