Super black
Super blackness is a surface treatment developed at the National Physical Laboratory in the United Kingdom . It reflects far less light than the darkest, conventional matte black colors that existed up to that point.
Conventional black paint absorbs about 97.5% of the incident light. The super black absorbs approximately 99.6% light at normal incidence . At other angles of incidence , super black is even more effective. For example, it absorbs almost 99.9% of the light at an angle of 45 °.
The technique used for Super Black is based on the chemical etching process of a nickel-phosphorus alloy.
application
Applications for super black can be found e.g. B. in specialized optical instruments to reduce unwanted reflections. The disadvantage of this material, however, is its low optical thickness, since it is a surface treatment. As a result, infrared light with a wavelength longer than a few micrometers penetrates the dark layer and has a much higher reflectivity. The specified spectral dependence increases from about 1% at 3 μm to 50% at 20 μm.
Alternatives
In 2009, a competitor to the super black material based on carbon nanotubes called Vantablack was developed, which has a relatively flat reflectivity in a broad spectral range.
In 2011, NASA and the US Army began funding research into the use of nanotube-based super black coatings in sensitive optics.
Nanotube-based superblack arrays and coatings have recently become commercially available.
Individual evidence
- ↑ Mini craters key to 'blackest ever black' . In: New Scientist . ( newscientist.com [accessed March 13, 2017]).
- ^ Highly Absorbing Surfaces for Radiometry. June 27, 2005, accessed March 13, 2017 .
- ^ Richard JC Brown, Paul J. Brewer, Martin J. T Milton: The physical and chemical properties of electroless nickel ??? phosphorus alloys and low reflectance nickel ??? phosphorus black surfaces " . Ed .: Journal of Materials Chemistry.
- ↑ NASA - NASA Develops Super-Black Material That Absorbs Light Across Multiple Wavelength Bands. Retrieved March 13, 2017 (English).
- ↑ Nanostructured Super-Black Optical Materials | SBIR.gov. (No longer available online.) Archived from the original on March 2, 2014 ; accessed on March 13, 2017 (English). Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Aligned Carbon Nanotube Arrays and Forests on Substrates. Retrieved March 13, 2017 .
