RPO chose the MICURA bridge-type CMM from Carl Zeiss Industrial Metrology. “Accuracy was our main concern, but the MICURA was also the right fit for measuring our small, intricate parts,” states Nick Gennarino, manager of Quality at Rochester Precision Optics. The compact MICURA 5/5/5 with VAST XT gold active scanning sensor is designed to provide submicron accuracy and low probing force with high-speed scanning rates of up to 200 points per second.
In addition to incoming, in-process, and final inspection, RPO uses the ZEISS CMM for first article inspection and design research. The most common components they measure are the metal or plastic barrels which will contain the lenses and are about 2 to 4 inches long. First, the material is machined to the required tolerances for various diameters, undercuts, grooves and threads. That is followed by the initial inspection on the CMM. Once the part is accepted, the lot will move through production, with machinists performing in-process checks with hand tools and carrying out periodic checks on the CMM. After the lot is completed, final inspections are done on the MICURA before and after the parts have been plated by a 3rd party. It’s critical to monitor part dimensions closely before and after the plating process because of the inherent risks of dimensional changes resulting from the plating process. Pre-plate dimensions are correlated with post-plate dimensions to better control the final product, improve efficiency and reduce waste. “You have to know what you’re putting into the plating process so you can expect good parts out of it,” states Nick. Once all of that is complete, they move to the assembly department. Targeted tolerances range from 3 to 10 microns and they currently measure about 40 barrels per week.