Differentiation between different microscope models
The difference between biological microscope and metallographic microscope is mainly in the lighting method and objective lens:
1. Biological microscopes use transmitted illumination, which is generally used to observe transparent and translucent samples and cannot be used to observe opaque objects. Metallurgical microscopes mainly use epi-illumination. The light source is emitted from the objective lens and is mainly used to observe opaque samples. Of course, there are also metallographic microscopes equipped with transmitted illumination devices, which can be used to observe transparent samples at the same time.
2. From the perspective of objective lenses, the high-power objective lenses of biological microscopes all consider the thickness of the cover glass (0.17) and the thickness of slides and culture vessels (1.2), so the objective lenses are usually marked /0.17 (upright microscope), / 1.2 (inverted microscope), the objective lens of an upright biological microscope with a power of less than 10 times is /-, which means it can be ignored. This is to correct the effect of glass on light refraction, and the objective lens of a metallographic microscope is usually marked with /0.
The difference between a biological microscope, a stereo microscope and a metallographic microscope. A stereo microscope is also called a stereomicroscope. The main differences from a biological microscope are as follows:
1. The working distance of a stereo microscope is relatively large, usually reaching 50mm or even 150mm; while the working distance of a biological microscope rarely exceeds 20mm.
2. Stereoscopic microscopes can place taller and thicker objects, such as integrated circuit blocks, larger workpieces, screws, thicker objects, etc., while biological microscopes can only place thin slices, slides, etc.
3. Stereoscopic microscope has a larger depth of field range, which can reach a depth of field of 10mm. By adjusting the focus ring, clear images can be seen over a wide range; while in biological microscopes, the focus ring may be slightly rotated and the image cannot be seen clearly.
4. A stereo microscope can see three-dimensional images because the depth of field range is wide. However, the magnification is small. Generally, the maximum magnification of a stereomicroscope is about 200 times; while the maximum magnification of a biological microscope is generally about 2,000 times. The characteristic parameters of a biological microscope are exactly opposite to those of a stereomicroscope. Therefore, the adaptability ranges of stereomicroscopes and biological microscopes are different, and the structure of the lens is also different.
