CEDAR FALLS - The group of Columbus High School physics students position small mirrors around a plastic Bart Simpson figure.

A clamp mounted on a table holds the figure in mid-air. Another clamp holds a slide on which the students have stuck decal letters spelling the word "cool." A laser mounted at the other end of the table shoots a red beam through the items.

"You need to think mainly how are you going to get light on this guy," said University of Northern Iowa professor Dale Olson, in reference to the figure. He is helping the students create a hologram in UNI's optics holography lab.

Columbus teacher Dan Kuchera brought his physics students to Olson's lab earlier this month as they finished studying the optics of light rays and prepared to move on to kinetic and potential energy and light waves.

"We currently have been doing light as a particle zipping around," said Kuchera. But that doesn't explain the refraction of the light necessary to make a hologram. Learning about holograms from Olson and helping to create one serves as introduction to the concept.

"These were the very first kind of holograms made by (scientist Dennis) Gabor," said Olson. However, he noted, Gabor did not use a laser when he created the process in 1948 because the device had not yet been invented.

A second group of Columbus students working in the lab is also positioning small mirrors around two slides they've created with decal letters spelling "CHS" and "YEAH."

A black curtain is pulled around the table to block all outside light as students prepare to expose high-quality film to the image. Then the laser is turned on and they open the shutter.

The slides, held with clamps, are bathed in the laser's red light. Columbus junior Erica Weilein said the film was exposed for about 12 seconds.

"You need to let as much light in as possible," she said. Afterwards, students from each group headed to a darkroom just outside of the lab to develop their film.

UNI senior Erick Zehr, who is completing a degree to become a science teacher, was helping Weilein's group create a hologram. He explained a powerful lens positioned between the laser and the image "spreads out" the red light into two beams. The two beams of light hit the image from different angles, interacting to make patterns of light and dark.

Zehr said bringing high school students into the lab is a good idea. It helps to "get people interested in science, get them interested in the world around them."

This is the second year Kuchera has taken students to Olson's lab. It provides an experience that wouldn't otherwise be available to the students.

"This is a little bit out of our range," Kuchera said, pointing to the costly lasers, table and other equipment. In addition, the field trip gives students "an opportunity to see what UNI has to offer."

Contact Andrew Wind at 291-1507 or andrew.wind@wcfcourier.com.