of Frame Measurements (Box System)
measurement of box enclosing lens area
of box enclosing lens area
of the lens along the central datum line
||Twice the distance
from the geometrical center of the lens to the bevel farthest away
between the horizontal and vertical measurements.
||The least distance
between the two lenses.
center distance also known as the DBC, distance between centers,
and sometimes referred to as the FPD or Frame PD, is the distance
from the geometric center of one eyewire to the geometric center
of the other.
the center of the center barrell screw hole to the end of the temple
tip.Length to bend. Measurement from the center of the barrel to
the middle of the bend.
||Length to bend.
Measurement from the center of the barrel to the middle of the bend.
||Front to Bend.
Distance between the plane of the frame front and the bend of the
temple. Applies to frames where the endpieces wrap around and there
is some distance between the frame front and the beginning of the