Eric Fossum, inventor of the CMOS active-pixel sensor used in digital cameras found in most mobile devices, looks at a toy car made by Andrew Roy, 7, during Inventors Camp at the Garrison School Thursday. Photo by John Huff/Staff photographer.

Participants in Camp Invention at Garrison Elementary School were in for a special treat Thursday morning.

Dr. Eric Fossum, the man who invented the technology which allows people to take pictures on their cell phones, visited the school to encourage children in the program to keep on dreaming.

“These are the future leaders in technology and invention,” Fossum said. “I hope to inspire them to take risks and be creative. You can’t teach them how to be creative, but you can nurture them to be so.”

Fossum, who lives in Wolfeboro, said he got his college degrees in physics and engineering. He was more of a “problem solver” rather than an inventor until he was in his mid-20s.

“It turned out, that is what invention is all about,” Fossum said.

In a breakout session with selected students, Fossum showed off the first prototype which eventually became the CMOS active pixel sensor camera-on-a-chip. Today, more than 90 percent of camera phones use this image sensor technology.

“In this bag, it’s a pretty small camera, not a product or anything. I took this camera around with me and took pictures on my laptop while on vacation,” Fossum said as he passed around the device he created.

Fossum also showed the students one of his inventors logs from 1980. All of the young inventors in the group have been using their own log during the course of this week. Many of them had Fossum sign theirs.

“In here, I wrote out all sorts of weird ideas. Some of them worked and some of them didn’t,” Fossum said as the campers studied the pages of graph paper Fossum flipped through.

Fossum has approximately 150 patents for his various inventions over the years, he said.

During Fossum’s tour of the camp, Dylan Pilla, 9, of Dover, showed off the battery-powered car he built in the program.

“The teacher wanted us to make these. I didn’t know if it was going to work or not but it actually did,” Dylan, who is going into fourth-grade at Horne Street School this year, said.

Bruce Erdmann and Kate Cassidy, both 8 years old and heading into third-grade at Garrison, showed Fossum their pinball machine made of a paper towel tube, tin foil, pencils, rubber bands and an old Dell computer.

“It is based on flippers and has a bug theme. You put the ball inside the tube and let go of the pencils. They come flying out,” Erdmann said as he explained how the machine works.

Patsy Eldridge, the regional program manager of Camp Invention, said the weeklong day camp for students in first- through sixth-grade encourages young minds through hands-on problem solving, using science, technology, engineering and math in a fun and creative atmosphere.

Camp Invention was founded by inductees of the National Inventors Hall of Fame. Fossum is a member

Fossum said he is used to working with college students as a member of the faculty at Dartmouth College, but he hopes more schools in New Hampshire will start to offer Camp Invention type programs to their learners.

“This is a very important age group developmentally,” Fossum said.