Testing Cylinder Surface By Hologram

Aspheric optical components are an important part of modern large-scale optical systems.With the development of optical technology,the demand for high-precision optical components of various shapes in optical systems is increasing.Cylindrical surface is one of the special conic surfaces.The cylindrical surface has different optical powers in the meridional and sagittal directions,which enables special imaging and has a unique role in the field of beam shaping.At present,the practical application of high-precision cylinders is still very limited.The main reason is that the test of high-precision cylinders is very difficult,which leads to the fabrication of high-precision cylinders as a bottleneck.The main work of this thesis is to study the test technology of large-size concave cylindrical surface,using computer-generated holographic and sub-aperture stitching technology.The test method can realize a set of optical path setup to test a batch of concave cylindrical mirror with any radius of curvature within a certain range,which can reduce the cost.The main task of the research work of this thesis is to solve the theoretical and technical problems of computational holographic design of large-aperture concave cylindrical surfaces,to study the one-dimensional stitching of cylindrical images of computational holography,and to develop a method for detecting large-aperture concave cylindrical mirrors.The research work of the thesis includes the following parts.1 Introduces the existing aspheric test method and its characteristics,investigates the use of this method in the traditional aspheric surface,analyzes its advantages and limitations,chooses the method suitable for cylindrical detection as the research direction,and lays the foundation for subsequent research.2 Explains the working principle of computer-generated holography,and analyzes the optimization changes to the design of the hologram and the optical path required to detect the cylindrical surface using computational holography.3 Design a calculation hologram example,and simulate the calculation hologram in the software to detect the cylindrical optical path.The parameters of the hologram are designed and obtained by means of ray tracing and software simulation,respectively,and the phase distribution and fringe coordinates of the hologram obtained by the two methods are compared.The simulation results show that the phase function calculated by ray tracing has good agreement with the software simulation results.4 Combined with the traditional aspheric sub-aperture stitching principle,the cylindrical sub-aperture stitching algorithm was optimized.First,one-dimensional cutting sampling is performed by using a the test results image obtained by experimental detection,and the splicing experiment is carried out with the cylindrical surface subaperture obtained by cutting to confirm that the reconstructed full-aperture shape is consistent with the original shape.Then,the results of a group of test images obtained by the experiment are stitched together to obtain the full-aperture profile image of the tested mirror surface.Build an experiment setup.Using the calculated hologram and the interferometer to test the cylindrical surface.