SBIR-STTR Award

Circuit cards are used in nearly every electrical appliance used by the military or by commerce. This naturally includes computers, which are themselves used in many electrical appliances. To assure quality, circuit cards must be checked for breaks and shorts. We propose five technologies which will allow imaging of electromagnetic fields on a circuit card. These technologies exploit the following physical effects: - electrodynamic forces - electrooptical materials - magnetooptical materials - piezoelectric materials (used for heating, and for deformation) Preliminary numerical estimates for most of the technologies have been carried out. The estimate for using electrodynamic forces appears to allow direct imaging, if tested at a sufficiently low frequency. Two other technologies appear to allow electromagnetic fields to be readily imaged after optical interferometry has been performed.

Circuit cards of one type or another are used in nearly every electrical appliance used by the military or by commerce. This naturally includescomputers, which are themselves used in many electrical appliances. Toassure quality, circuit cards must be checked for breaks, shorts, and impropercomponents. The industry has many testing techniques but none exploit thediffering electromagnetic field that a faulty card produces. Our Phase I research showed that the electrooptical effect (Pockels effect) canbe used to detect the electrical fields from a low power digital circuit board.We propose to prototype a complete system that will, when scaled up, becapable of comparing the electromagnetic fields from two circuit cards. Thissystem uses a two dimensional (2 x 4) array of electrooptical sensors for the field detection (in a commercial system this must be scaled up to, approximately, a 100 x 100 array). The prototyped system will also obtain images (of a portion of a circuit board) and use them to compare two boards against one another.

Keywords:
ELECTROOPTIC EFFECT ELECTRODYNAMIC FORCES IMAGING INTERFEROMETRY MAGNETOOPTIC EFFECT