Large membrane space optics: imagery and aberrations of diffractive and holographic achromatized optical elements of high diffraction order

The imagery and aberrations of a large space telescope using a 100-m-diam f/100 diffractive objective are evaluated. Excellent imagery can be obtained with flat membrane optical surfaces. Interactive effects of the spectral fan of a diffractive optical element with the free- flying system architecture are considered. The parametric relationships of achromatized diffractive optical elements (DOEs) and holographic optical elements (HOEs) are explored as a function of diffraction order, focal ratio, and wavelength. Practical aspects of a pair of crossed linear DOEs are discussed. Procedures to design achromatic DOE systems are detailed and typical results presented. A number of practical issues associated with making and using high-order transmissive and reflective DOEs and HOEs are identified.