Fine focusing knob

Definition

The fine focusing knob is a part of the microscope used to make small adjustments to the focus, enhancing the clarity and detail of the specimen being viewed. It is typically employed after the coarse focusing knob has brought the specimen into general focus.

5 Must Know Facts For Your Next Test

1. The fine focusing knob is essential for achieving sharp, high-resolution images under higher magnification.
2. It only moves the stage or objective lenses by a very small amount, allowing for precise control.
3. Fine focusing knobs are particularly important when using high-power objective lenses (40x and above).
4. Using the fine focus knob can help avoid damaging slides or objectives, which can occur if only the coarse focus is used.
5. In compound microscopes, both coarse and fine focusing knobs are usually found on the same side of the microscope.

Review Questions

• What role does the fine focusing knob play in microscopy?
• Why is the fine focusing knob particularly important at higher magnifications?
• How does improper use of only coarse focus affect slide observation?

Related terms

Coarse Focusing Knob: Moves the stage or objective lenses significantly to bring a specimen into general focus.

Objective Lenses: Lenses closest to the specimen; they gather light from it and create an image.

Stage: The flat platform where slides are placed for observation under a microscope.