Polymer NdFeB Hard Magnetic Scanner for Biomedical Scanning Applications

Micromirror scanners are the most significant of the micro-optical actuator elements with applications in portable digital displays, automotive head-up displays, barcode scanners, optical switches and scanning optical devices in the health care arena for external scanning diagnostics and in vivo scanning diagnostics. Recent development in microscanning technology has seen a shift from conventional electrostatic actuation to electromagnetic actuation mechanisms with major advantages in the ability to produce large scan angles with low voltages, remote actuation, the absence of the pull-in failure mode and the acceptable electrical safety compared to their electrostatic counterparts. Although attempts have been made to employ silicon substrate based MEMS deposition techniques for magnetic materials, the quality and performance of the magnets are poor compared to commercial magnets. In this project, we have developed novel low-cost single and dual-axis polymer hard magnetic micromirror scanners with large scan angles and low power consumption by employing the hybrid fabrication technique of squeegee coating to combine the flexibility of polydimethylsiloxane (PDMS) and the superior magnetic performance of fine particle isotropic NdFeB micropowders. PCB coils produce the Lorentz force required to actuate the mirror for scanning applications. The problem of high surface roughness, low radius of curvature and the magnetic field interaction between the gimbal frame and the mirror have been solved by a part PDMS-part composite fabrication process. Optimum magnetic, electrical and time dependent parameters have been characterized for the high performance operating conditions of the micromirror scanner. The experimental results have been demonstrated to verify the large scan angle actuation of the micromirror scanners at low power consumption

Software based bioassay quantization using standard optical disc drives

This thesis describes the application of the compact disc technology as a rapid, low-cost, high capacity-screening platform for bioassays. Although the compact disc has been used by modifying the hardware of the detection mechanism (CD-drive) to achieve a ubiquitous and low-cost detection of biomolecules, minimal or no modification is ideal. This thesis investigates the possibility of an inexpensive, software based bioassay detection on CDs with, standard computer drives. Using a CD data analysis software called IsoBuster, biotin-streptavidin binding assays prepared on compact discs are read detected and quantized using error based detection mechanism with a high spatial accuracy. The research shows a sensitivity of detection of 270 μg/mL of streptavidin in solution with biotin-modified dis