Silicon Carbide Optics

Last Update: 11/18/02

More Info
	Technology Description Validation Plan Stray Light Issues References

Credits
	NASA Official/Author: Nick Speciale Curator: Trish Johnson Leslie Allen Development Credits Official Notice: Privacy Statement

Summary Overview Benefits Contacts

Silicon Carbide offers the advantage of very high stiffness to density ratio and very high conductivity to heat capacity ratio.

These characteristics are superior to currently used materials for reflective optical systems.

The high stiffness to density ratio of silicon carbide (SiC) allows mirrors of very low weight to be designed and still maintain the necessary surface figure to provide the performance required for high resolution optical imaging. Light weight optics lead to light weight optical metering structures required to support them. This in turn leads to lighter instruments and therefore lighter payloads. Currently, only beryllium can compete with SiC for the lowest mass for a given optic size. SiC has the additional advantage of high thermal conductivity with relatively low thermal heat capacity. This properly allows minimum thermal gradients for a given heat load. This is an advantage for an optical system in a low Earth orbit that experiences changes in thermal boundary conditions on a regular basis. SiC performs without competition in this arena. This leads to an optimum optical system design of SiC optics with a SiC optical metering structure. Using the high stiffness to weight ratio, a very low weight optical system can be constructed..

The impact of silicon carbide (SiC) on 21st Century science will be quite profound. SiC optics and structures have the potential of lowering optical system weights an order of magnitude over current conventional systems. This lowering of weight means smaller and lighter payloads. This leads to the potential for more missions for a given funding level.

Dexter Wang
Telescope Manager / President
Sensor Systems Group
Phone: (978) 694-9991
Email: dexterw@ssginc.com

Joseph Young
EO-1 Mission Technology Transfer Manager
NASA Goddard Space Flight Center
Phone: (301) 286-8146
Fax: (301) 286-1736
Email: joseph.p.young.1@gsfc.nasa.gov