O
- object speed limit
- object table
- ophthalmic lens
- Ophthalmometer
- Ophthalmoscope
- Ophthalmoscope graticules
- optical axis
- optical centre
- optical centre distance OCD
- optical dimensions
- optical material
- optical radiation
- Optical radiation hazard
- optical zone of magnifier
- Optimization
- Organic hard resin: thermoplastic hard resin
- Organic hard resin: thermosetting hard resin
Ophthalmometer
An instrument designed to measure and indicate the radii of curvature and principal meridians of the human cornea's, central area and of contact lenses.