Classification of filters for microscopes
1. Sunlight filter: When using artificial light sources, the field of view turns yellow. The red and yellow staining details of stained specimens are difficult to distinguish. The use of light blue filter 209 can change artificial light sources to approximate natural light. The light blue glass slide attached to a regular microscope belongs to this type of filter.
2. Green filter: When observing the red details on the specimen, using a green filter can increase the contrast, i.e. contrast, of the specimen details. It is more important to perform micrographs on black and white films. Because general panchromatic films are particularly sensitive to blue and green light, and are slow to red light. The negative of the sample stained with SuMu Zi Yi Hong is too bright without a green filter. When using a green filter, the blue color of the specimen details is absorbed to create a natural image. Therefore, when performing micrographs on black and white films, it is best to use the 211 transparency curve 510-590nm filter from the Livi filter series.
3. The yellow green filter with a high absorption rate is very important for observing unstained specimens with low contrast, such as cultured cells
4. The 510nm No. 212 filter in the Livi series also performs well in observing live cells. When there is too much contrast in the microscopic R image and the details of the object image are unclear, using a yellow filter can appropriately display the blue details of the specimen.
5. The 209th filter in the Livi series has a transparency of 430-480nm and can be used to observe yellow and green stained specimens and their microscopic images.
6. In the early days, liquid endothermic filter devices were used to prevent infrared thermal radiation from damaging the optical components. The lighting fixtures of modern large microscopes are equipped with endothermic glass filters that can be placed in or out of the optical path.
These filters can be replaced by liquid filters or self-made in difficult conditions. Specific details will be introduced in the appendix of this chapter.
In addition to using filters in conventional microscopy techniques, some special filters are used in fluorescence microscopy techniques. Such as wide spectrum transparent excitation filter, high-performance narrow spectrum excitation filter, high-performance wide spectrum strong excitation filter, namely interference filter, blocking filter, color separation filter, etc.
