Eye On Inspection
The human eye is an amazing organ but sometimes it needs a little help. With press speeds reaching 1,000 fpm, operators would have a hard time catching print blemishes and other defects on the web if it wasn’t for inspection systems.
All inspection machines can help printers save money and to explain the types of inspection systems on the market, packagePRINTING asked industry experts for their input.
Explain the difference between inspection systems available in the package printing marketplace.
• Jim Doerr, president and CEO, TruColor Vision Systems: Currently, the market is filled with inspection options. Features, advantages, and system benefits can be as varied as the amount of capital it requires to invest in inspection technology. Choices include: human eye, rotating mirrors, high-intensity strobes and, of course, machine vision type systems. TruColor Vision Systems now offers a complete range of machine vision-based inspection systems beginning with the basic entry level models, then on to midrange automated models—automated in terms of automatically positioning and moving the inspection camera around the web.
• Nat Stern, CEO and VP, eltromat electronics: There are essentially two types of print inspection systems, 100 percent and samples. Sampled uses an area camera strobe arrangement on a traverse and is capable of very fine inspection. These systems are mainly for preventive control where defects are detected before they become serious. The shortcoming is little chance of finding sporadic defects. One hundred percent systems generally use line cameras and have less sensitivity than sampled systems. They are very good at catching sporadic defects and are usually the choice for inspection rewinds.
• Tim Lydell, CEO, Label Vision Systems: There are several inspection-type systems in the market, from simple sensors to complex wide-web systems that operate at very high speeds. LVS operates in the middle of this range with a print inspection system that has the complexity to provide complete inspection of print quality of static print as well as truly variable print from label-to-label at high speeds. This is the LVS 7000 product. A sensor will look at only one or two areas on a label as it passes the inspection station. It does not have the intelligence to make decisions, only determine if it saw what it expected to see.