A New Full-Aperture Reflective Null Measuring Method for Conformal Dome

Yan, Xudong;Wang, Junhua;Xu, Min

  • Received : 2015.12.29
  • Accepted : 2016.02.03
  • Published : 2016.02.25


In this paper, a novel full-aperture reflective null measuring method is proposed to detect the transmission wavefront of a conformal dome surface. An aspheric compensator is designed and placed behind the dome to reflect the aspheric testing wave back to the same path. To ensure the feasibility of this method, tolerance analysis is conducted, and guidance to assembly is given accordingly. The accuracy of this method is verified to be λ/30 (λ =3.39 μm) by Monte Carlo algorithm. In addition, the influence of different error factors, including the thickness error and decenter error of the dome, on the testing wavefront is analyzed. Simulation and experiment indicate that this method is practical and simple, and can measure the conformal domes precisely and comprehensively.


Precision metrology;Conformal dome;Reflective null testing;Interferometry;Tolerance analysis


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