In a neat twist of physics, the same phenomenon that enables CCD and CMOS imagers to change light into electronic images also allows photovoltaic cells to change the sun’s visible radiation into a source of electric power. These two manifestations of the photoelectric effect are having a substantial impact on the world in the forms of increased use of solar energy and new production techniques that incorporate machine vision.
As the demand for solar energy grows, companies involved in the manufacture of solar cells and panels are automating their production systems with vision-guided robots and wafer inspection systems. In our cover story for this issue, editor Andy Wilson describes a machine-vision system that uses structured lighting to measure the curve, or bow, in a solar wafer, and thus reduce breakage and waste further down the production line.
Light—and the creative capture of it—is central to the design of the machine-vision system described in an article by contributing editor Winn Hardin. In this case, Aptúra Machine Vision Solutions has devised a system that uses reflected light to check for reagents that coat the insides of glass tubes. The tubes are for a portable blood-testing system used in remote locations to identify and hopefully help defeat diseases such as malaria.
Once products are properly lit, captured images must often be rapidly processed by autonomous camera systems. Many of the advances in both image capture and processing are being enabled by smart cameras that incorporate on-board processing capability. As editor Andy Wilson writes in his Product Focus article, some camera vendors have realized the value of incorporating microcontrollers, DSP functionality, and LED lighting into their products. As a result, these cameras can offer both fast image-processing and system-control functions.
Advances in creatively harnessing the power of light and smart camera technology are required to maintain the rapid integration of machine vision into industrial and nonindustrial applications. While LED lighting has been used for years in many of these applications, new demands such as solar-panel inspection require new approaches to lighting and image processing to ensure a cost-effective, high-quality product.
Using light in different and creative ways, it seems, is now beginning to deliver many benefits both for energy conservation and the developers of machine-vision systems.