<title>Wavefront coding technology in the optical design of astronomical instruments</title>

The new astronomical instruments; spectrographs, cameras, focal reducers, telescopes, etc., requires to work in more and more wide spectral ranges and with very large fields of vision. Therefore, the chromatic aberrations and the field curvature are aberrations very difficult to correct and to balance in the process of optical design. For that problem, in the stage of optical design is necessary to add more optical components in the instrument, also we need to use more aspherical surfaces and we need more time of optical design, etc. In this work we propose to use the technique of wavefront coding using a cubic phase mask to obtain optical systems with an extended depth of field that corrects the chromatic aberration and the field curvature automatically. In this paper we present preliminary results of this technique.