Parfocal Stage
Definition
A microscope stage on which the specimen remains approximately in focus when switching between objectives, enabling rapid survey across magnification ranges without repeated re-focusing.
- Component
- Microscope stage
- Function
- Keeps specimen approximately in focus across objectives
- Benefit
- Rapid survey without repeated re-focusing
- Related term
- Parfocality
Common questions
How does a parfocal stage speed up microscopic examination?+
An examiner can switch between low and high magnification objectives without adjusting focus each time, letting them scan a specimen quickly before zooming in on a region of interest.
Does parfocal mean perfectly in focus at every objective?+
No. It means approximately in focus, and a small fine-focus adjustment is usually still needed to sharpen the image after switching objectives.
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