pin4dp>The PIN-4X4D is a 2-dimensional, 4 by 4 array of superblue enhanced Photodetectors. The desn provides virtually complete isolation between all of the 16 elements, and a standardBuy OSI Optoelectronics, PIN-SPOT-4D Si Photodiode, Through Hole TO-5 . Browse our latest Photodiodes offers. Free Next Day Delivery available.