Patent attributes
The optical transfer function of imaging optics is carried out with a plurality of tilted edges with respect to the edge-response detection line. The effect of the tilt is to stretch out the edge response so that fine details can be detected even operating at a spatial frequency below the Nyquist limit of the detector. The use of multiple targets, each corresponding to a sub-region of the field of view of the optics being tested, enables the simultaneous characterization of the full field of view of the test optics with a single measurement without the use of a magnifying objective. The result is a rapid measurement and a simpler apparatus suitable for high-throughput testing. A pair of tilted edges can be used in a target to also determine the sagittal and tangential OTFs (as well as that of any other arbitrary cross-section). All of these data are acquired with a single measurement.
