Patent ID: 6023057
Filing Date: 2000-02-08
Classification: G01J,G02B

Abstract:
A device for determining the phase errors of electromagnetic waves (OE) which are generated by a light source and transmitted by an optical instrument, said device (1) comprising:a reception system (SM) which comprises at least one measurement plane (PM, PM3, PM4) provided with a plurality of measurement zones (ZM) which can measure the intensity of the received light;a collimation means (L1) for sending to said measurement plane (PM, PM3, PM4) the electromagnetic waves (OE) transmitted by said optical instrument;a defocusing system (SD1, SD2) which can send at least one pair of associated planes (P1, P2), which are conjugate with a pupil plane of the optical instrument, to said reception system (SM) for them to be measured;a computation unit (UC) which determines said phase errors on the basis of measurements taken by said reception system (SM) on said associated planes (P1, P2); anda spatial filter (F) which is arranged in an image plane (PI) of the optical instrument, said spatial filter restricting the area of the light source seen by said reception system (SM) while allowing the spatial spectrum of said phase errors to be transmitted, said spatial filter (F) comprising an opaque mask provided with a hole (T) having a diameter, said diameter of said hole (T) being greater than the diameter of the aberration spot produced by the phase errors at the image plane, said filter (F) having a Gaussian profile of the intensity of the light transmitted by the optical instrument.