Characterization of ion-exchanged planar microlenses by ray tracing

For the design and optimization of the fabrication condition of distributed-index planar microlenses, it is necessary to evaluate the N. A., focal length, focused spot, and aberration of a fabricated lens. In this paper, a ray tracing method is improved for this purpose, and properties of planar microlenses aie evaluated. An ion concentration matrix is proposed to simplify lens design.

A signal-processing research facility and its application to the processing of fetal phonocardiographic signals for heart rate estimation

Part 1 of this paper describes a real-time medical signal-processing research facility which is being developed at Edinburgh University. Part 2 describes the application of this facility to the estimation of fetal heart rate from phonocardiographic signals using a new frequency-domain estimation algorithm.