How to distinguish different microscopes
The difference between a biological microscope and a metallographic microscope mainly lies in the lighting method and objective lens:
1. Biological microscopes use transmission lighting, which is generally used to observe transparent and semi transparent samples, and cannot be used to observe opaque objects. Metallographic microscopes mainly use falling beam lighting, where the light source is emitted from the objective lens and mainly used to observe the surface of opaque samples. Of course, there are also metallographic microscopes with transmission lighting devices that can be used to observe transparent samples simultaneously.
2. From the perspective of objective lenses, the high-power objective lenses of biological microscopes take into account the thickness of the cover glass (0.17) and the thickness of the slide and culture vessel (1.2). Therefore, their objective lenses are usually marked with/0.17 (upright microscope) and/1.2 (inverted microscope), while the objective lenses of upright biological microscopes below 10x are/-, which can be ignored. This is to correct the influence of glass on light refraction, while the objective lenses of metallographic microscopes are usually marked with/0.
The difference between a biological microscope, a stereomicroscope, and a metallographic microscope is also known as a stereomicroscope. The main differences between a stereomicroscope and a biological microscope are as follows:
1、 The working distance of a stereoscopic microscope is relatively large, usually reaching 50mm or even 150mm; The working distance range of biological microscopes for detecting objects 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 sheets, glass slides, etc.
3、 A stereoscopic microscope has a large depth of field range, up to 10mm. By adjusting the focusing ring, clear images can be seen over a considerable range; The biological microscope may not be able to see clearly by slightly rotating the focusing ring.
4、 Stereoscopic microscopes can see three-dimensional images due to the wide range of depth of field. However, the magnification is relatively small, and generally, the maximum magnification of a stereoscopic microscope can reach around 200 times; The maximum magnification of a biological microscope is generally around 2000 times, and the characteristic parameters of a biological microscope are exactly the opposite to those of a stereomicroscope. So, the adaptation range of stereomicroscopes and biological microscopes is different, and the structure of the lens is also different.
