To provide a wavefront measuring device capable of easily measuring a wavefront in a short time.
A wavefront measuring device for measuring a transmission wavefront of an optical element or its reflection wavefront comprises: a sensor that includes a lenslet array and a detector array and can be arranged at a first position and a second position; and a signal processing part that calculates at least one of wavefront aberration, a wavefront shape on an arbitrary surface, a complex amplitude distribution and a surface shape of the optical element on the basis of an intensity signal obtained from the sensor. The signal processing part estimates a first wavefront using a first intensity signal obtained by arranging the sensor at the first position, sets the first wavefront as an initial value, estimates a second wavefront through repeated light propagation calculation using the first wavefront and a second intensity signal obtained by arranging the sensor at the second position, and uses the second wavefront to calculate at least one of the wavefront aberration, the wavefront shape on the arbitrary surface, the complex amplitude distribution and the surface shape of the optical element.
Atsushi Mizumoto
Hirayama Tomoya