INTERFEROMETRE FOR MONITORING ASPHERICAL QUADRATIC SURFACES Russian patent published in 2010 - IPC G01B11/24 G01B9/02 

FIELD: physics.

SUBSTANCE: interferometre has a source of monochromatic radiation, an afocal system and a first beam splitter designed for splitting radiation into two branches - standard and operational. A plane mirror, a focusing lens and a lens for forming a standard plane wave front are placed in the standard branch. A second plane mirror, a second focusing lens in whose back focus there is a diaphragm, and a lens for forming a controlled plane wave front with possibility of it moving out of the operational beam, are placed in the operational branch. After the lens which forms a standard plane wave front there is a second beam splitter for combining the standard and the controlled wave fronts. An interference pattern recording unit which has an input lens and a photodetector is placed in the output light beam. A third plane mirror is fitted after the second beam splitter, perpendicular to the standard wave front beams passing it. The focusing lens in the standard branch can be moved along an optical axis. In the front focus of the lens which forms a controlled plane wave front there is a second diaphragm which can be moved out of the operational branch.

EFFECT: more reliable monitoring of aspherical quadratic surfaces due to possibility of independent inspection of flatness of the standard wave front using apparatus which are part of the interferometre.

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