Can be connected to TV or computer display. A drop of blood test to see ovulation, mites. Professional Microbiology Research.
Bright background/black background, two options.
What is black background?
No dust particles floating in the air can be seen in a bright room. When the curtains are closed or the lights are turned off, the room is completely dark, and then a projection lamp is turned on. At this time, it will be found that the light path illuminated by the projection lamp will be transparent or semi-transparent. Transparent little dust.
The black background uses this principle to see more transparent or opaque impurities that cannot be seen on the white background, such as triglycerides, platelets, parasites, etc.