If a Student Uses a Parfocal Compound Light Microscope,which of the Following

Question

If a student uses a parfocal compound light microscope,which of the following would be true?
A) The focus will have to be adjusted using the mechanical stage control knob.
B) After the initial focus adjustments are made, the image should remain in focus as the specimen is viewed with each objective lens.
C) The focus will have to be adjusted using the coarse adjustment knob.
D) The focus will have to be adjusted using the fine adjustment knob.

Accepted Answer

A parfocal compound light microscope is designed to remain in focus even when different objective lenses are used. Thus, after the initial focus adjustments are made, the image should remain in focus as the specimen is viewed with each objective lens. The mechanical stage control knob is used to move the slide, while the coarse adjustment knob is used for initial focusing and the fine adjustment knob is used for fine-tuning. However, with a parfocal microscope, the focus does not need to be constantly readjusted with each change of objective lens.