Silicon Carbide Lightweight Optics With Hybrid Skins for Large Cryo Telescopes, Phase I

Metadata Updated: February 28, 2019

Optical Physics Company (OPC) proposes to manufacture new silicon carbide (SiC) foam-based optics that are composite, athermal and lightweight (FOCAL) that provide an enabling capability for performing NASA space missions that will require 2 to 3 meter class cryogenic mirrors for large infrared telescopes. Open-cell foam core mirror technology has evolved over the past ten years and has produced somewhat large (0.5 m dia.), lightweight (<10 kg/m2), rapidly and uniformly cryo-cooled and dimensionally stable (tested to 25 K) mirrors configured with monolithic chemical vapor deposited (CVD) skins. Significant problems have arisen as the size has increased that prevent their use on large aperture telescopes. These problems include the inherent stress in the monolithic skins which can result in skin cracking during the substrate manufacturing and finishing processes, the non-uniformity of the .040"-.050" thick monolithic skins that typically require .010"-.015" of material removal before a continuous surface can be achieved for optical finishing, the long schedule of manufacturing the mirror substrate, and the large $2M/m2 cost to produce the polished mirror. OPC proposes an innovation where the monolithic SiC skins are replaced with SiC fiber reinforced/SiC CVD skins. This hybrid design consists of a .020"-.030" thick SiC fiber reinforced layer ground to a smooth finish and near net shape, and then post coated with a .005"-.010" thick CVD SiC polishing layer. This provides increased skin strength and toughness to enable the technology to produce meter class mirrors without skin cracking. The manufacturing time and CVD chamber cost are reduced because premanufactured SiC fibers are used to provide the bulk of the skin mass rather than laying down a monolithic skin atom by atom via CVD. The net effect is to produce a SiC FOCAL mirror substrate that is stronger, tougher, scalable to meter class, and potentially better than 50% faster and cheaper to manufacture.

Access & Use Information

Public: This dataset is intended for public access and use. License: U.S. Government Work

Downloads & Resources


Metadata Created Date August 1, 2018
Metadata Updated Date February 28, 2019

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date August 1, 2018
Metadata Updated Date February 28, 2019
Publisher Space Technology Mission Directorate
Unique Identifier TECHPORT_7988
Maintainer Email
Public Access Level public
Bureau Code 026:00
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id 9e459414-42ed-449c-acaa-99f8a5614049
Harvest Source Id 39e4ad2a-47ca-4507-8258-852babd0fd99
Harvest Source Title NASA Data.json
Data First Published 2009-10-01
Homepage URL
Data Last Modified 2018-07-20
Program Code 026:027
Source Datajson Identifier True
Source Hash 389bae80fdb59f72e15238aa82c29171cc3538fb
Source Schema Version 1.1

Didn't find what you're looking for? Suggest a dataset here.