A grating pattern containing bright and dark bars that are each 0.25 deg wide has a spatial frequency of:
A) 0.25 cpd
B) 4 cpd
C) 2 cpd
D) 5 cpd

Question

Quizplus · Accepted Answer

Spatial frequency is measured in cycles per degree (cpd). Since each cycle consists of one bright and one dark bar, the total width of one cycle is 0.5 degrees (0.25 deg for a bright bar + 0.25 deg for a dark bar). Therefore, the spatial frequency is 1 cycle per 0.5 degrees, which is 2 cycles per degree (cpd).

A Grating Pattern Containing Bright and Dark Bars That Are