With photonics business leaders forecasting market growth, manufacturers will have their hands full preventing production bottlenecks. Ironically, logjams are more likely as a plant approaches full capacity. Miscues can slow production dramatically and leave long lines of items waiting to be processed. Managers who delay ordering can make the problem worse. "Customers are waiting until the last minute and then they need their product yesterday," said Dave Smith, general manager of Melles Griot Optical Systems in Rochester, N.Y. "A couple of years ago [they] were willing to [commit] their orders six months in advance. They felt more confident about selling the product. Now customers are more hesitant to risk making the commitment to buy that far out." At Oxford Lasers Ltd. in Abingdon, UK, that unevenness is an unavoidable part of business. "We do large systems and thi ngs come all at once," said project engineer Heather Booth. "When we're busy, lead time is estimated on a project-by-project basis." Still, she said, many things can go wrong. Human resources might stretch too thinly, or unexpected supplier problems could wrench production into low gear. Queue-switched "The name of the game is to reduce your queue time," Smith said, and balancing short- and long-term demands is one place to start. Manufacturers also look to the process to identify and eliminate the root causes of bottlenecks. That job may be easier when companies gather manufacturing data at important points in the process. "When you have monitors in place and things go out of whack, you know it," said Jack Flagel, quality assurance supervisor at Dalsa Inc. in Waterloo, Ontario, Canada. Such a monitoring system takes a problem-solving approach to analyzing what causes bottlenecks. Regardless of whether the problem is a glitch in the machinery or an inefficient process, the aim is to take action to reflow activity and prevent a recurrence. Having the information on hand can also yield insight into things like downtime or the cost of a rejected item. Cross training employees can help smooth production, Flagel said, as long as the training itself doesn't cut into on-the-job productivity. In some cases, adding capacity is the only answer. Sean Ogarrio, an industrial designer at SDL Inc. in San Jose, Calif., pointed to the company's 980-nm laser pump modules as an example of a product that creates bottlenecks. He said there are so few suppliers that "we've had to develop new techniques to keep up with demand." Even so, the company plans to add a new facility.