Tips for choosing inverted microscope

2022-08-09
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Tips for choosing inverted microscope

1: optical part: the core of microscope quality is its optical part, that is, eyepiece and objective lens. Generally speaking, the objective lens can be divided into several levels. The first is achromatic objective lens. With this objective lens, not all parts of the image are clear, only about 60% of the central range of the field of vision is clear, and 40% of the peripheral part will have certain defects. Usually, we place the observation part in the center of the field of vision, so it does not affect the observation. But if you want 100% vision without defects, you need to use flat field achromatic objective lens. Relatively speaking, the price of this kind of lens will be much higher, which is generally used in medical treatment and scientific research. There is also a half flat achromatic objective between the two. Students can choose the first two levels with the microscope. So that waste plastics can be reused. Generally, the cheaper objective lenses are ordinary achromatic ones, and the transaction price is about 8000 yuan. A better one is the apochromatic objective lens or the infinite apochromatic objective lens, and the transaction price is about 10000 yuan. If it is for three purposes, the price is still several thousand yuan higher. Therefore, it is relatively simple for users to purchase eyepieces, that is, to see the size of their field of vision. It is recommended to use eyepieces with large field of vision, because eyepieces with large field of vision have larger openings and better visual effects than ordinary ones. However, under normal circumstances, customers who choose inverted microscope use three purposes more

2: structural materials: for example, the body structure of the microscope. The service life of the microscope is very long, some of which can reach more than 10 years. Then high-quality parts and strict assembly have become the guarantee of the service life of the traditional machine equipment manufacturers when developing and trial producing new parts. Therefore, we should choose a microscope with a stable and solid frame, and the best material is alloy, which can reduce deformation. In addition, the size of the stage is also very important. Generally, the larger the stage, the higher the price of the microscope will be, because the larger the stage, the larger the sample port can be placed, the larger the observation area is, and it is more convenient to move its samples for observation

3: light source part: microscope observation can have light sources such as bright field, dark field, polarized light, phase difference, fluorescence, etc. different functional microscopes use different observation methods, and their functions are also different

bright field image (BF): select the image formed by direct electrons (transmission beam), and the image is clear. General bright field light source is the most common light source that will change our life

dark field image (DF): choose the image formed by scattered electrons (diffractive beam), the image has distortion and low resolution. Many customers of dark field light source don't understand it. Here we explain the matter of dark field observation for specific dark field characteristics: dark field observation: dark field is actually dark field illumination. Its characteristics are different from the bright field of vision. It does not directly observe the light of illumination, but the light reflected or diffracted by the tested object. Therefore, the field of view becomes a dark background, and the tested object presents a bright image

the principle of dark field of vision is based on the optical tindol phenomenon. When the dust passes through the strong light directly, the human eye cannot observe it, which is caused by the diffraction of the strong light. If the light is oblique to it, due to the reflection of light, the particles seem to increase their volume and become visible to the human eye. The special accessory required for dark field observation is the dark field condenser. Its characteristic is not to let the light beam pass through the tested object from bottom to top, but to change the path of the light to make it oblique to the tested object, so that the illumination light does not directly enter the objective lens, and use the bright image formed by the reflected or diffracted light on the surface of the tested object. The resolution of dark field observation is much higher than that of bright field observation, up to 0.02-0.004. Polarized light is a light source used to study so-called transparent and opaque anisotropic materials. All substances with birefringence can be clearly distinguished under polarized light observation. Of course, these substances can also be observed by staining, but some are impossible, and polarized light must be used. Generally, polarizing microscopes cost 5000-8000 yuan for the whole family, and those who buy polarizing microscopes are best to use monochromatic light, because the speed, refractive index, and interference phenomenon of light vary due to different wavelengths. Ordinary light can be used for general microscopic examination. As for the phase difference light source, it has been introduced previously

fluorescent light source: it uses a certain wavelength of light to excite the specimen to emit fluorescence, and magnifies it through the objective lens and eyepiece system to observe the fluorescent image of the specimen. Therefore, most fluorescent light sources are used in fluorescent microscopes

4: mesh number of inverted microscope: normal customers of inverted microscope use more three eyes, which is actually binocular. Basically, single eyes are rarely used on inverted microscope, which should be said to be almost none. Therefore, many domestic manufacturers only produce binocular and three eye sum. Generally, the price difference between binocular inverted microscope and three eye inverted microscope including two production lines is about 2000 yuan

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