Image-analysis system VISTA for automatic inspection of unsealed blisters filled with tablets

Abstract
Unsealed blisters filled with tablets are automatically checked by using a well-proven multi-level threshold method (1). All serious defects as missing or interchanged tablets are detected. Other defects as broken tablets, missing print on a tablet, spots or additional little pieces are detected with high reliability. As an essential progress in comparison to a former development (2) the image acquisition equipment is easy adaptable to different packaging machines and products, the operation interactions are immensely reduced by implementing a highly automated teaching procedure and in spite of doubling the throughput the sensitivity of the system is increased. The great sensitivity has been achieved by high image resolution (0,2 mm x 0,2 mm) and automatic recalibration procedures after each measurement cycle.