Parfocality
Definition
The property of an objective nosepiece turret such that switching objectives keeps the specimen approximately in focus without re-focusing; defined by ISO 10934-1.
- Defined by
- ISO 10934-1
- Applies to
- Objective nosepiece turret
- Effect
- Minimal refocusing needed when switching objectives
Common questions
What standard governs parfocality in forensic microscopes?+
ISO 10934-1 sets requirements for microscopes used in forensic applications, including parfocality specifications for the objective turret.
Why does parfocality matter for comparison microscopy?+
It lets an examiner move between magnifications quickly while comparing evidence, cutting the time spent re-focusing and lowering the risk of losing the field of view.
Related terms
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