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D
- D-segment
- decentration
- depth perception
- design reference point
- differential light sensitivity, S
- differential luminance, DL
- digitally rounding focimeter
- dimensions of lens blanks or lenses
- dioptre
- dioptric power
- Direct ophthalmoscope
- dispersion
- display magnification
- display size
- distance cap
- Distance dependent ophthalmometer
- distance design reference point
- distance optical centre
- distance portion
- distance portion curve
- distance reference point
- distance visual point DVP
- diverging lens
- dividing line
dioptre
Unit of focusing power of a lens or surface, or of the vergence (refractive index divided by the radius) of a wavefront. NOTE1: Commonly used symbols for this are D, dpt and δ. NOTE2: Dioptre is expressed in reciprocal metres (m-1)