Dalsa MotionVision CA-D6-0256W-ECEW, Руководство пользователя

Страница: 22 / 38

22
CA-D6-xxxxW User’s Manual
03-32-00225-06 DALSA INC.
m
h
h
= ′
where m is the magnification, h’ is the image height (pixel size)
and h is the object height (desired object resolution size).
By similar triangles, the magnification is alternatively given by:
m
f
OD
= ′
These equations can be combined to give their most useful form:
′ = ′
h
h
f
OD
This is the governing equation for many object and image plane
parameters.
Example: An acquisition system has a 512 x 512 element, 10
µ
m pixel pitch area
scan camera, a lens with an effective focal length of 45 mm, and requires that
100
µ
m in the object space correspond to each pixel in the image sensor. Using the
preceding equation, the object distance must be 450 mm (0.450 m).
10
100
45
450 0 450
µ
µ
m
m
mm
OD
OD mm m
= =
( . )