TEST CELL FOR NON-CONTACT OPENS/SHORTS TESTING OF ELECTRICAL CIRCUITS

摘要

A test cell for non-contact testing a circuit board for shorts and opens includes a hermetically sealable container for that circuit board, at least one wall of the container providing access to permit a circuit board to be positioned at an imaging plane inside the container. A pair of planar electrodes positioned inside the container are spaced on opposite sides of and parallel to the imaging plane and these electrodes are connected to contacts on the exterior of the container so that the electrodes can be releasably connected to an external voltage source to provide an electric field inside the container which extends perpendicular to the imaging plane. One of these electrodes and the container wall adjacent thereto are transparent to light from a pulsed laser positioned outside the container which is arranged to image a selected spot on a conductor of a circuit positioned at the imaging plane. One or more valved gas fittings are mounted to the outside of the container so that the container can be releasably connected to external gas conduits to fill the container with an inert gas. Also a sensor may be provided inside the container to sense the gas pressure in the container.