World's blackest material aids space imaging
A UK nanotechnology company has developed the world's blackest material, which promises to improve the sensitivity of electro-optical imaging systems.
The Vantablack material from Surrey NanoSystems is based on carbon nanotube technology and absorbs 99.96 per cent of incident radiation, believed to be the highest ever recorded, according to the company.
Materials that reflect very little light are useful as absorptive coatings for thermal detectors, blackbody cavity coatings, and for use in optical instruments to reduce stray light.
In an Optics Express paper, the company, working alongside the UK National Physical Laboratory and Enersys’ ABSL Space Products division, has reported a procedure for depositing the material onto aluminium substrates for Earth observation applications. The ‘super black’ material will also be launched at the Farnborough International Air Show.
‘Vantablack is a major breakthrough by UK industry in the application of nanotechnology to optical instrumentation. For example, it reduces stray-light, improving the ability of sensitive telescopes to see the faintest stars, and allows the use of smaller, lighter sources in space-borne black body calibration systems. Its ultra-low reflectance improves the sensitivity of terrestrial, space and air-borne instrumentation,’ commented Ben Jensen, chief technology officer at Surrey NanoSystems.
The manufacture of 'super-black' carbon nanotube-based materials has traditionally required high temperatures, preventing their direct application to sensitive electronics or materials with relatively low melting points. This, along with poor adhesion, prevented their application to critical space and airborne instrumentation. However, Surrey NanoSystems has successfully transferred its low-temperature manufacturing process from silicon to aluminium structures and pyroelectric sensors.
Vantablack has the highest thermal conductivity and lowest mass-volume of any material that can be used in high-emissivity applications, according to the company. It has virtually undetectable levels of outgassing and particle fallout, thus eliminating a key source of contamination in sensitive Space imaging systems. It withstands launch shock, staging and long-term vibration, and is suitable for coating internal components, such as apertures, baffles, cold shields and MEMS optical sensors.
‘We are now scaling up production to meet the requirements of our first customers in the defence and space sectors, and have already delivered our first orders,’ added Jensen.
As a spin-off from its work in applying nanomaterials to semiconductor device fabrication, Surrey NanoSystems’ manufacturing process also enables Vantablack to be applied to flat and three-dimensional structures in precise patterns with sub-micron resolution.