1. Optical part:

The core of the quality of a microscope is its optical components, namely the eyepiece and objective lens. For objective lenses, they can generally be divided into several levels. Firstly, there is an achromatic objective. When using this type of objective, not all areas of the image are clear, only about 60% of the central field of view is clear, and there may be some defects in the 40% peripheral area. Usually, we place the observation part in the center of the field of view, so it does not affect the observation. But if you want a 100% field of view without defects, you need to use a flat field achromatic objective, which is relatively expensive and is generally used in medical and scientific research. There is also a semi flat field achromatic objective that falls between the two. Students can choose the first two levels of microscopes to use. The generally cheaper objective lenses are ordinary achromatic objective lenses, with a transaction price of around 8000 yuan. The better ones are either achromatic lenses or infinite distance achromatic lenses, with a transaction price of around 10000 yuan. If it is for three purposes, the price will be several thousand yuan higher. So when users choose eyepieces, it is relatively simple to look at the size of their field of view. It is recommended to use a large field of view eyepiece because it has a larger opening compared to regular eyepieces, resulting in better visual effects. However, under normal circumstances, customers who choose inverted microscopes tend to use three purposes.

2. Structural materials:

For example, the body structure of a microscope has a long service life, some of which can reach more than 10 years. Therefore, high-quality components and tight assembly become the guarantee of its service life. Therefore, a microscope with a stable and sturdy frame should be chosen, and the material selection should be alloy, which can reduce deformation. In addition, the size of the stage is also important. Generally, the larger the stage, the higher the price of the microscope. This is because the larger the stage, the larger the sample port can be placed, and the observation area is relatively large, making it easier to move the sample for observation.

3. Light source section:

Microscopic observation can have light sources such as bright field, dark field, polarization, phase contrast, fluorescence, etc. Different functional microscopes use different observation methods and their functions are also different

Bright field image (BF): Select an image formed by direct electron beam (transmission beam), with clear image. General bright field light sources are ordinary light sources

Dark field image (DF): The image formed by scattering electrons (diffracted beam) is selected, which has distortion and low resolution.

Many customers are not familiar with dark field light sources. Here, we will provide a more in-depth explanation of the specific dark field characteristics of substances in dark field observation: Dark field observation: Dark field observation is actually dark field illumination. Its characteristics are different from the bright field of vision, as it does not directly observe the illumination light, but instead observes the reflected or diffracted light of the object being tested. Therefore, the field of view becomes a dark background, while the inspected object presents a bright image.