JPH0527084B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method of taking a microscopic image of a sample surface using an optical microscope.

(B) Prior art In general, optical microscopes are widely used because they are easy to prepare samples to be observed, are easy to operate, can distinguish colors, and are inexpensive. ing. Although optical microscopes have many advantages as described above, they have the disadvantage that because of their shallow depth of focus, it is not possible to obtain clear optical microscope images by photographing samples with curved or uneven surfaces. For this reason, in the past, only samples with relatively flat surfaces were observed. When observing samples with curved or uneven surfaces, stereoscopic microscopes and scanning electron microscopes are mainly used. However, in the former case, the magnification is at most several ten times, which is not sufficient. In the latter case, a high magnification of tens of thousands of times can be obtained, but there are drawbacks such as complicated preparation of the sample and operation of the device, inability to distinguish colors, and high price.

(c) Purpose The present invention has been made in view of the above-mentioned problems, and is intended to enable clear optical microscope images to be taken even for samples whose surfaces are curved or uneven. The purpose is to solve the problems of the conventional technology.

(D) Configuration As shown in Figure 1, the light intensity of an optical microscope image is at its maximum when it is focused on the sample surface, and when it deviates from the focus position to a certain extent, it becomes a constant background intensity regardless of the sample position. The present invention focuses on this point, and in order to achieve the above object, the distance between the sample and the lens barrel when focusing on the most convex part of the sample within the field of view of the sample. , between the distance between the sample and the lens barrel when focusing on the most concave part of the sample, and move at least one of the sample and the lens barrel of the optical microscope from one distance to the other within the photographic exposure time. Scanning is performed in the optical axis direction. For example, if the amount of light is sequentially integrated onto the film, only the in-focus area will be exposed accordingly, resulting in a photographed image that is in focus as a whole.

(E) Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 2 is a schematic diagram of an optical microscope to which the present invention is applied. In FIG. 2, 1 is an optical microscope, 2 is a lens barrel with a built-in magnifying lens (not shown), 3 is a camera attached to this lens barrel 2, 4 is a sample to be observed, and 5 is this sample 4 This is a stage for placing. A rack portion 5a is formed on the stage 5, and a pinion 6 is meshed with the rack portion 5a. 8 is a synchro motor for rotationally driving the pinion 6, and 9 is the camera 3 mentioned above.
The shutter 10 is a control unit that controls the operations of the synchro motor 8, shutter 9, and the like.

Next, a method of taking an optical microscope image of the sample 2 by applying the optical microscope 1 having the above configuration will be explained.

First, the sample 4 is placed on the stage 5. It is assumed that the surface of the sample 4 on the lens barrel 2 side is not flat but has irregularities as shown in FIG. 3a. Next, the stage 5 is moved in the optical axis direction of the optical microscope 1 (Z direction in FIG. 2). Then, while looking through the lens barrel 2, focus on the most convex part of the sample 4 ( _point A in the figure) within the field of view of the sample 4. The distance between the sample 4 and the lens barrel 2 at this time is defined as _Z1 . Next, the stage 5 is moved to focus on the most concave portion of the sample 4 (point A ₂ in the figure) within the same field of view. The distance between sample 4 and lens barrel 2 at this time is Z ₃
shall be. Each distance Z ₁ , Z ₃ between the sample 4 and the lens barrel 2 above
is stored in the control unit 10. Subsequently, the sample 5 is positioned at the initially set distance _Z1 , and from this state the control section 10 is operated to open the shutter 9 and photographing is started. At the same time as the shutter 9 is released, the synchro motor 8 is also driven, and the pinion 6
Rotate. Then, the stage 5 is scanned at a constant speed in the optical axis direction until the sample 4 reaches a distance _Z3 set later (in this example, it is moved downward). During this time, the shutter 9 remains open in conjunction with the synchro motor 8, and when the predetermined distance _Z3 is reached, the synchro motor 8 stops and the shutter 9 closes. In this way, the sample 4 is scanned in the optical axis direction from one distance Z ₁ to the other distance Z ₃ within the photographing exposure time, so as time passes, the light amount corresponding to each part of the sample 4 changes to the third It changes sequentially as shown in Figures b to d. Therefore, images are accumulated on the film of the camera 3, and parts corresponding to the focused parts are exposed one after another. As a result, a photographed image that is in focus within the field of view as a whole is obtained. Background fog occurs during scanning, but this can be removed by adjusting the sensitivity of the film, the aperture of the camera 3, the brightness of the illuminator (not shown), the photographic paper, the printing conditions, etc. I can do it. In the above example, from position Z 1 where the focus is on the most convex part of sample 4 to position Z ₁ where the focus is on the most concave part.
Although the sample 4 is scanned by the Z ₃ , the opposite case may be used, and furthermore, the lens barrel 2 may be moved instead of moving the sample 4 side. Furthermore, sample 4
The lens barrel 2 and the lens barrel 2 can also be moved closer to each other or separated from each other.

(f) Effects As described above, according to the present invention, a clear optical microscope image can be obtained even if the sample surface is not flat by changing the relative positional relationship between the lens barrel of the optical microscope and the sample. Furthermore, it can be realized at a much lower cost than a scanning electron microscope. Also,
It has the excellent effect of being able to capture images even at a magnification of several hundred times, something that could not be achieved with a stereo microscope.

[Brief explanation of drawings]

Fig. 1 is a characteristic diagram explaining the relationship with the amount of light when focused on the sample surface, Figs. 2 and 3 show embodiments of the present invention, and Fig. FIG. 3, which is a block diagram of the optical microscope, is a characteristic diagram showing the relationship between the shape of the sample surface and the amount of light when focused on the sample. 1... Optical microscope, 2... Lens barrel, 3... Camera, 4... Sample.

Claims (1)

[Claims] 1 A method of taking an optical microscope image of a sample with an uneven surface, which measures the distance between the sample and the lens barrel when focusing on the most convex part of the sample within the field of view of the sample, and the distance between the sample and the lens barrel. During the exposure time, move at least one of the sample and the lens barrel in the direction of the optical axis of the optical microscope from one distance to the other. A method for taking an optical microscope image, characterized by scanning.