sealPurdue News

June 2001

Spectraline Inc. shines its light on quality control

WEST LAFAYETTE, Ind. – A high-tech company in the Purdue University Research Park is taking industry into the far end of the spectrum for the purpose of on-line quality monitoring.

Spectraline Inc. has developed the ES 100 Mid-Infrared Imaging Spectrometer, an instrument that uses infrared light to monitor quickly and easily the quality of products in a wide variety of industries, including the petrochemical, dairy and beverage industries.

The ES 100 scans materials by using light from the infrared region of the electromagnetic spectrum, light the human eye cannot see. That region is divided into near-, mid- and far-infrared.

The consistency of a liquid product, such as gasoline or milk, usually is tested for quality when technicians take random samples from the production line to the laboratory and analyze them using bench top instruments. The ES 100 is the first spectrometer operating in the mid-infrared region that is designed specifically to constantly monitor the product as it flows through the manufacturing process.

"Our technology reduces unnecessary waste," said Rony Joseph, Spectraline's vice president of product development. "By continuously monitoring the liquid flow with our spectrometer, operators can immediately revise the process the moment something fails to meet specifications rather than waiting until an entire batch has been ruined."

Other spectrometers that work in the mid-infrared region have been developed, but the ES 100 is the fastest. While available instruments can complete a scan in one second, the ES 100 can take 390 complete scans in the same amount of time, enabling it to capture rapidly changing phenomena. A high-speed scan also enables large numbers of samples to be collected, which then can be averaged together to reduce "noise" or other conditions that might interfere with readings.

Previously developed mid-infrared spectrometers are delicate instruments that rely on high-precision mechanisms for moving mirrors and gratings within the instrument. They are designed for use in the lab, not for rugged on-line applications, Joseph said. In addition, their lifetimes are limited to about 10,000 hours because they use cryogenic coolers, which also have many moving parts.

The shoe box-sized ES 100, however, can withstand being moved around the factory floor because it has no moving optical components. The instrument also features a photosensitive detector made of lead selenide that uses a much less expensive cooling system and has a proven lifetime of more than 100,000 hours.

On top of shortcomings with durability and speed, most near-infrared spectrometers are lying idle because of the extensive calibration required to block out background influences such as sunlight, room light and heating sources.

"The ES 100 won't take the user six months to a year to calibrate before use and won't need to be re-calibrated repeatedly," Joseph said. "Our instrument will be shipped factory-calibrated with a customized database for the particular product to be monitored. The user won't need to perform any calibrations and the instrument can be deployed straight out of the box."

The ES 100 can be used in three modes: emission mode, to study turbulent flames, monitor gas turbine combustors and utility furnaces; absorption mode, to monitor multiple constituents in flowing liquids; and reflectance mode, to monitor solids and powders. These methods can be used to measure fat in milk, sulfur in gasoline, and glucose in blood; to detect the presence of poisonous gases; to monitor a gas turbine or an engine to find out how lean it is running; or to monitor the spoilage of fruits and bacteria in meats and other foods.

Spectraline also makes the LS 100 and LS 200 linescan video cameras, which use infrared technology for thermal imaging. The LS 100 can be used to generate thermal maps of objects such as hot-rolled steel or aluminum sheets, while the LS 200 can provide surface temperatures of objects.

Spectraline licensed the technology for the ES 100 from En'Urga Inc., which was founded in 1994 by Yudaya Sivathanu, a research scientist in Purdue's School of Mechanical Engineering. En'Urga formed Spectraline in 1999 to develop the instrument further for commercial applications.

Spectraline has its headquarters in one of the Purdue Research Park's small-business incubators where more than 35 companies have access to professional business assistance. The park's incubator concept provides high-tech venture companies with shared office services, flexible leases and attractive rental rates.

Sources: Rony Joseph, (888) 884-8236;

Yudaya Sivathanu, (765) 497-3269;

Writer: Jeanine Smith, (765) 496-3133;

Purdue News Service: (765) 494-2096;

NOTE TO JOURNALISTS:  A publication-quality color photograph of the ES 100 is available by calling Jeanine Smith at (765) 496-3133. Technical specifications on the ES 100, LS 100 and LS 200 can be obtained by visiting the Spectraline Web site.

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