A METHOD FOR DETECTING MISSING COMPONENTS AT ELECTRICAL BOARD TEST USING OPTOELECTRONIC FIXTURE- MOUNTED SENSORS

摘要

A METHOD FOR DETECTING MISSING COMPONENTS AT ELECTRICAL BOARD TEST USING OPTOELECTRONIC FIXTURE-MOUNTEDSENSORSAbstractDisclosed is a method and apparatus for determining the presence or absence of a component on a printed circuit board. The method andapparatus utilizes a photo-sensor and photo-detector that are positionedwithin a predetermined non-contacting distance from the expected locationof a given component under test. The photo-emitter emits a controlled amount of light energy on the expected location of the component under test on the printed circuit board. The photo-sensor detects the amount ofreflection off the surface of the expected location of the component under test. Because the amount of reflection differs between reflection off thesurface of the component under test and reflection off the surface of the bare board, based on the reflection measurement, the component under test can be classified as either present or absent at its expected location on the printed circuit board.FIG. 4 ACCOMPANIES THIS ABSTRACT