The two-dimensional measurement principle for a birefringence vector distri
bution in transparent materials is analyzed. The system nonuniformity that
results from the system components makes the two-dimensional measurement pr
inciple quite different from that of a point-measurement method, and the me
asurement principle requires a two-dimensional analysis. A pulsed optical p
hase modulation is employed to simplify the two-dimensional mathematical an
alysis. As a result, concepts are proposed of the system function that char
acterizes the system nonuniformity that results from the system components
and of the intrinsic function that is related to the birefringence vector d
istribution in a birefringent sample. The influence of the system nonunifor
mity on the two-dimensional measurement is eliminated by measurement of the
intrinsic function, whereas its two values allow for the mathematical sepa
ration of the birefringence vector components. The effectiveness of the two
-dimensional analysis is illustrated by measurement of a birefringence vect
or distribution, which is induced by an internal stress distribution in a p
oly(methyl methacrylate) plate, owing to the photoelastic effect. (C) 1999
Optical Society of America.