T
- telemicroscope
- terms relating to transmission, reflection and coatings
- terrestrial telescope
- test stimulus
- test stimulus pattern
- test tonometer
- threshold differential luminance, DLT
- threshold stimulus luminance, LT
- Threshold strategy
- tinted lens
- toric lens
- toroidal surface
- tracer
- trademark
- transmittance in the infrared A
- transmittance in the infrared B
- transmittance in the solar infrared spectrum
- transmittance in the solar ultraviolet A spectrum (SUVA)
- transmittance in the solar ultraviolet B spectrum (SUVB)
- transposition
- trial case lens
- trial frame
- trifocal lens
toroidal surface
Part of the surface generated by a circular arc rotating about an axis which is in the same plane as the arc but which does not pass through its centre of curvature. NOTE: It is desirable to restrict the term 'toroidal' to a surface and the term "toric" to a lens or object.