Carbon nano technology enables miniaturised optical devices
A team of researchers from the University of Surrey’s Advanced Technology Institute (ATI) has grown vertically aligned carbon nanotubes (CNTs), in a grid-like formation on glass. The CNTs create wafer-thin, flat structures that could enable the miniaturisation of a range of optical devices. Removing the need for traditional curved refracting lensing systems, which can be bulky and expensive, will enable new compact optical systems based on this nanotechnology.
The material is either highly transparent or opaque depending on its angle with respect to the beam. This property makes it ideal for either collimating a beam of visible white light; or for absorbing stray light that is off the axis of the CNTs. This is said to enable significant improvement to line-of-sight applications such as optical data transfer, or the rejection of stray light in high specification space telescopes.
James Clark from the ATI explained: “One approach to realising compact optical systems, which is an alternative to that used here, is a Veselago lens which is made from artificial ‘metamaterials’. However, currently the obstacles in translating this theory to practical use are numerous.”
Professor Ravi Silva, director of the ATI, added: “Collimation maintains an accurate record of the image and is classically done by using two lenses, each with a specific shape and placed a certain distance from each other. What we have shown in this study is that carbon nanotubes grown in this way can produce a well-collimated beam of visible light using a single flat material, a practical feature of a Veselago lens. This will lead to a new approach to small and flexible optical devices.”
The next step for this work is to incorporate this material into existing technology. The ATI has already demonstrated low-temperature growth processes to enable direct wafer-scale integration of vertical CNTs with CMOS devices.
Other news ...
- - March
- - June