PORTLAND, Ore. A University of Delaware engineer claims to have solved a power issue that has prevented wider use of digital light processors (DLP) in power-sensitive applications.
DLPs normally use microelectromechanical systems (MEMS) to control the angle of micromirror arrays. However, for power-sensitive applications such as space exploration, even the microamps required to tilt micromirrors make use of DLPs prohibitive.
This year's recipient of the National Science Foundation Career Award, Balaji Panchapakesan, a University of Delaware engineering professor, claims to have solved the problem using micro-optomechanical systems. MOMS use lasers to actuate tiny mirror-tipped cantilevers instead of electrical current to power pnematic, piezoelectric or electrostatic actuators.
An optically-active nanotube film enables MOMs to be actuated by a ultralow-power laser rather than power-draining electrical current. The researcher claims power consumption is low enough for space exploration and new applications of field-emission displays and biomedical scanners.
The technique patterns a carbon nanotube thin-film using standard CMOS processing steps, resulting in arrays of optically-actuated cantilevers measuring 300 microns long by 30 microns wide by 7 microns thick. The cantilevers deflected 23 microns when their base was illuminated by a 808-nm wavelength, 170 mW semiconductor laser.
Panchapakesan also claimed to have accumulated expertise on directly patterning thin films of nanotubes. Details are described in the current issue of Applied Physical Letters.
The University of Delaware has received a provisional patent for its technique.
Next, Panchapakesan's team will attempt to make the cantilevers wavelength selective by refining the structure and physical properties of the underlying carbon nanotubes used to make thin films. Also planned is a demonstration of MOMS applications that will illustrate how semiconductor laser actuators enable different nanorobotic mechanisms.