Abstract: A method for measuring such parameters as height, position, shape, colinearity, and coplanarity of arrays of minute objects on the surface of integrated circuits, such as Ball Grid Arrays (BGA), all in one simple and straight forward procedure during the manufacturing process of integrated circuits. Shadows of the objects are created on the substrate through the use of x-rays or other light sources placed at predetermined distances and angles from the objects. An imaging device obtains images from the shadows cast onto the substrate and the images are then analyzed to determine if they meet predefined parameters. Multiple sources of illumination can be used to illuminate the array in order to create a more precise image for analysis and three dimensional images of the BGA can be created for analysis.

Abstract: For accurate position calculation of scintillation events in a gamma camera, photodetector signals are processed based on small groups of photodetectors surrounding the scintillations. Relative position correction and energy correction is carried out based on rough position values relative to the group of photodetectors, taking into consideration the number of the center photodetector and the sum of all photodetector signals in the group.