Yu.V. Bazhanov1, I.I. Oleinikov2, A.P. Pericov3

1–3 JSC "Precision Systems and Instruments" (Moscow, Russia)(Moscow, Russia)
 

Design of the optical scheme of an off-axis three-mirror telescope based on an integrating mirror combining the first and second mirrors is reported. Based on aberration theory, we established a suitable initial configuration for integration mirror design. Optimization was carried out using the ZEMAX program using a free-form surface in the form of a power polynomial. The design calculation of a three-mirror decentered optical system with a common freeform mirror is performed, the influence of the angular field on the dimensions and image quality is analyzed. An optical systems with a focal length of 1000 mm, a relative aperture of 1:12, and an angular fields of 8х3º and 15х1º, providing a diffractive image quality in the visible spectral region, has been obtained. With three independent mirrors, the field of view of the lens reaches a value of 12x6º. Since the integrated mirror is described by one expression, it can be manufactured from a single installation on a multi-axis diamond-turning machine. Another advantage of this type of lens is that the mounting of mirrors of two-mirror lenses with three beam reflections is an axisymmetric design. The alignment of such schemes is much easier compared to two-mirror lenses, since the mirrors in this case are deployed relative to each other, and even more so compared to three-mirror lenses. To simplify the implementation of such systems, namely, to further simplify the alignment and increase the mechanical strength, we will limit ourselves to systems in which the secondary mirror and the radiation receiver are mounted on the same plane or on parallel closely spaced planes. The alignment of such system becomes extremely simple.

Bazhanov Yu.V., Oleinikov I.I., Pericov A.P. Design of decentered three-mirror optical systems with a common free-form mirror. Information-measuring and Control Systems. 2023. V. 21. № 3. P. 127−134. DOI: https://doi.org/10.18127/j20700814-202303-16 (in Russian)

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