FIELD: information technologies.
SUBSTANCE: device comprises a lens of spherical aberration correction, having one surface shaped with a larger curvature compared to the other surface; and a sliding part that slides along a guide element. The protruding part of the sliding part is configured so that it is installed within the limits of the side surface of the reflective surface of the upward reflecting mirror, and a part of the spherical aberration correction lens protruding away from a lens holder, is applied onto the reflective surface of the upward reflecting mirror, when the lens of the spherical aberration correction is approaching the upward reflecting mirror as close as possible.
EFFECT: reduced dimensions of the device and increased range of spherical aberration correction.
15 cl, 8 dwg
