David Collins worked at Pennsylvania Railroad, developed the barcodes to address the problems faced in accurately tracking train cars. He developed a system called KarTrak with reflective stripes made from phosphorescent ink that can be easily read by light and pasted on train cars. He used blue and yellow reflective types, encoding a six digit company identifier and a four digit car number. The first test using this system was conducted by Boston & Main on gravel cars in 1961. In 1967, many experiments have taken place and a nationwide standard for a coding system was adopted. Th economic downturn in the mid 1970’s killed the system as a flurry of railroad bankruptcies gutted industry budgets. Collins, in 1967, founded his own corporation called Computer Identics. Then he started to work on automatic identification technology. He used black and white barcodes but the light source was replaced with a helium neon laser beam that scanned the barcodes from several feet away. The laser light source was smaller, cooler, and could move back and forth at faster rates over the barcodes. This made the process simpler and reliable and it allowed to deal with the damaged labels.
Computer Identics Corporation installed two scanners one in General Motors plant in Pontiac, Michigan, to monitor the production and distribution of automobile axle units and the other in General Trading Company in Carlsbad, New Jersey, to help direct shipments to the proper loading bay doors.
Middle stages are the period were the development of barcode technology has seen greater transformation and most importantly it has been commercially applied.