15.ObservationMake observations using darkfield microscopy
Make observations using darkfield microscopy
What is darkfield microscopy?
Darkfield microscopy is a method of using oblique illumination to observe unstained specimens.
Use high contrast to make light observation images visible on a dark background.
When using darkfield microscopy, the illumination source is focused in a circular shape by the diaphragm ring. The light passes through the edge of the condenser lens and illuminates the specimen obliquely.
By using a lens with a smaller numerical aperture than the condenser lens, only the scattered light in the specimen passes through the objective lens and will form a darkfield image.
Preparing for darkfield microscopy
The parts listed below can be used.
Darkfield slider
Objectives lenses for darkfield microscopy
The objective lenses that can be used with darkfield microscopy have restrictions such as the ones listed below.
When using darkfield microscopy NA0.65 or less
When making observations in the light field position NA 1.25 or less
Make observations using darkfield microscopy
Raise the stage, remove the condenser and the dummy slider in it.
After inserting the darkfield slider, return the condenser, and adjust the position with the condenser’s vertical movement knob.
Place the darkfield position in the light path, set the open aperture lever to the same numeric value as the objective lens, and bring it into focus.
After adjusting stage height with the coarse adjustment knob, bring it into focus with the fine adjustment knob and observe.
