The main difference between a dark field microscope and an ordinary microscope is the way of illumination. It illuminates the specimen with a strong, narrow, slanted beam without letting the beam enter the objective lens. When no light enters the objective lens, the field of view is dark, so it is called dark field microscope. However, because the particles in the specimen can scatter light after being illuminated by light, when the scattered light enters the objective lens, the scattered light spots of the particles can be seen in the microscope, as if the particles themselves were glowing. This is just as in a dark room, through a small hole in the wall of a strong beam of sunlight, we can see the presence of dust in the light path. This phenomenon, in optics, is known as the Dundar phenomenon. The dark-field microscope is designed according to this principle.
Applications
For observing microorganisms, colloid chemistry, single-celled organisms, and objects with linear structure Unsuitable for observing stained specimens
Procedure
1. Sample preparation 2. Assembly and adjustment of dark field microscope 3. Observation
Materials
• Sample Type: Bull sperm cells
Notes
Operate in strict accordance with the operating procedures, and shall not arbitrarily change the operating procedures