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What do the markings on a microscope objective mean?
Choose an example objective, then tap a marking to see what it tells you about the lens and your sample.
Step 1 · Choose an example
Step 2 · Tap a marking
The objective
The red circle shows the selected marking. Illustrative drawing; markings and colour conventions can vary.
Step 3 · Read what it means
Marking explained
Explore another common marking
Quick guide
Three things to check before using an objective
1. Cover glass
Check whether its correction marking matches the glass or vessel between the lens and your sample.
2. Immersion medium
Oil, water and glycerol objectives require the specified medium; an unmarked dry lens usually uses air.
3. Microscope system
Infinity and finite objectives need the optical system they were designed for. Check the full specification before swapping objectives.