Fabrication of large-aperture lightweight diffractive lenses for use in space

Abstract

We describe the advantages of using diffractive (Fresnel) lenses on thin membranes over conventional optics for, among others, future space telescope projects. Fabrication methods are presented for lenses on two types of freestanding membrane up to 50 cm in size. The first is a Fresnel lens etched into a thin (380-microm) glass sheet, and the second is an approximately 50-microm-thick polymer membrane containing a Fresnel lens made by replication process from a specially made fused-silica master. We show optical performance analysis of all the lenses that are fabricated, including a diffraction-limited Airy spot from a 20-m- focal-length membrane lens in a diffractive telescope system.

Error analysis of large-diameter subaperture stitching Fresnel diffractive elements

“…Interest in using large-aperture diffractive optical elements (DOEs) for fabrication of the primary lenses of space telescopes has largely been discussed in specialized literatures [1][2][3][4][5][6], and they present interesting benefits when compared with other alternatives. For instance, DOE-based primary lenses show loose surface shape tolerance and are lightweight.…”

Transferring diffractive optics from research to commercial applications: Part I – progress in the patent landscape

“…Finally, due to the extreme different dispersive characteristics of DOEs, compared to refractive lenses, they allow an advantageous combination of both to form hybrid imaging systems with optimized performance and compactness. To name a few, the imaging hybrid concept was applied to eyepieces [1][2][3][4][5], head-mounted displays (HMDs) [6][7][8], inspection systems for semiconductor manufacturing industry [9,10] and also for new concepts of space telescopes [11,12]. In this field, the activities of the Japanese company Canon attracted very high interest.…”

First high dynamic range and high resolution images of the sky obtained with a diffractive Fresnel array telescope

“…Several proposals have been made in the recent years for using Fresnel zone plates in space, held by, or painted on transparent plastic foils: [3,4,6,15], but these proposals have never been implemented successfully. Others for making images in the X-ray domain, now also for UV and visible wavelengths, propose diffraction through circular holes: "photon sieves" [1,16].…”