Shorter than a Schmidt.
Abstract
This paper is concerned with spectrograph cameras. It is shown that a system consisting of an aspheric plate, a spherical mirror and a self-achromatic lens some distance in front of the focus can be corrected for spherical aberration, coma, astigmatism, field curvature and chromatic difference of focus over a wide spectral range. Compared with a Schmidt camera of the same focal length, these systems have an overall length that is considerably shorter, by an amount that can be controlled in the design. Numerical data are given for three designs, of relative aperture f/2.5.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- August 1977
- DOI:
- 10.1093/mnras/180.3.485
- Bibcode:
- 1977MNRAS.180..485W
- Keywords:
-
- Astronomical Photography;
- Cameras;
- Optical Properties;
- Spectrographs;
- Aberration;
- Astigmatism;
- Curvature;
- Lenses;
- Photographic Plates;
- Schmidt Cameras;
- Astronomy