Nonparaxial geometrical Ronchi test for spherical mirrors: an inverse ray-tracing approach
What's it about?
Usually, ronchigrams are generated by the direct ray-tracing method. However, the resulting image is parametrized by the coordinates in the plane of the mirror. This parameterization produces irregularly sampled images (scattered pixels). We propose for the first time a model for the generation of ronchigrams parametrized by the pixel array. The model considers concave spherical mirrors such as the used in Newtonian reflector telescope for beginners.
Why is it important?
The derived model provides a clear relationship between the observed image in the Ronchi test and the parameters of the system; for example, the radius of the mirror, the position of the source point, and the position and orientation of the image plane. This suggests new applications of the Ronchi test such as calibration and alignment of compound optical systems.
New potential applications of the Ronchi test are possible. However, for this to be achieved, some generalizations are required. For example, include in the model other mirror surfaces such as parabolic, elliptical, or even free form.