Born in Brooklyn, Olsen grew up a rambunctious child in eastern New Jersey. He was arrested at 16 for stealing hubcaps, suspended at Jersey’s Richfield Park high school for misbehavior, and generally recalls spending lots of time underneath his clunky ‘54 Chevy, which he bought for $25. After graduation, Olsen barely avoided going into the military when his cantankerous father, an electrician, told him that it was difficult to get into the Local 3 Union without six months of college. Olsen enrolled in Farleigh Dickinson, fell in with a studious crowd (three foreign exchange students) and went on to earn undergraduate and masters degrees in physics and a PhD in material sciences at the University of Virginia. His dad was “quite proud,” Olsen says, and would brag to his fellow barflies about his son’s accomplishments.

Out of school, Olsen landed a job at RCA Laboratories developing the indium gallium arsenide crystals used in RCA’s photodetectors and lasers. He wore a white lab coat for 11 years before getting the entrepreneurial itch and founding his first company, Epitaxx, to use those crystals in fiber optic equipment. The company occupied space in a modest Princeton lumberyard where the Prince Tennis racquet company got its auspicious start. Six years later, Olsen sold Epitaxx to the Japanese for $12 million–just before the bottom fell out of the Japanese economy.

Others might have squirreled away their fortune and headed to the beach. Divorced, with two adult daughters, Olsen did just that, living in a friend’s Clearwater, Fla., condo for three months while pondering the rest of his life. But that lifestyle quickly bored him. Theorizing about the use of his crystals in cameras, he applied to various government agencies for grants and scored several; he also plugged his entire fortune into the new venture, which he dubbed Sensors Unlimited. “My net worth for five or six years was zero,” Olsen says of the early days, when he was guaranteeing loans from banks with personal credit. Sensors Unlimited moved into the same charmed lumberyard offices once occupied by Epitaxx. One of the first applications for its new infrared cameras was peering through a painting’s outer layer to see an artist’s early modifications. For example, Olsen’s camera found that Renoir had altered a former friend’s face in his famous work, “Luncheon of the Boating Party.”

Though the art world proved small and unprofitable for Sensors Unlimited, Olsen had timed the market perfectly once again. As the Internet and other electronic communications took off, telecom companies started laying miles of the fat cables needed to send digital signals around the globe. Olsen’s crystals, situated on either end of a network, ensured that bouncy electrons would make a smooth journey across hundreds of miles. The infrared cameras quickly became a side business as the firm swelled to over 120 employees.

After taking buyout offers from big telecom players like Lucent and Alcatel, Olsen sold the firm to the California-based Finisar Corporation for $700 million in August 2000–a few months before the telecom industry imploded in its best imitation of the dot-com world. Olsen and his partners stayed with the company and eventually bought it back for seven million after the bust. They had to lay off half the staff– “something I hope I never have to do again,” Olsen says. Then they refocused on the original cameras and a range of new applications, like finding the micro flaws in silicon wafers made by companies like Intel, and letting the military see through camouflage clothing and paint.

With the money he made from the sale to Finisar, Olsen has been exploring new avenues opened by his wealth. “I want to throw off the barriers and get rid of the blinders,” he says. Though he continues to live in the same modest Princeton bachelor pad, he bought a ranch in Montana, a winery in South Africa and a condo in Manhattan’s towering new Time Warner Building. He also gave $15 million to his alma mater, the University of Virginia and runs a family foundation with his daughter Krista. (For the last ten years, Olsen has also personally mentored a Trenton, N.J., student through the Big Brothers-Big Sisters program.) “He’s a true American success story and an inspiration to many,” said Virginia Congressman Virgil H. Goode, a fellow University of Virginia graduate.

Then there’s the little matter of that $20 million ticket to the International Space Station. Sensors Unlimited president Marshall Cohen says Olsen’s trip to space is only partly selfish. “While he’s motivated by personal exploration, I don’t think he’d do it without establishing other benefits,” like conducting scientific experiments on the station and inspiring kids. Daughter Krista says the mission is totally in keeping with the character of her spontaneous dad, who has learned to ice skate, climbed Mt. Fuji and taken up ballroom dancing, all on apparent whims.

Olsen himself talks about his reasons for traveling to space from his Princeton home, taking turns lifting grandkids Justin and Carter high into the air. As the kids squeal, granddad says he has no intention of simply taking an eight-day joy ride. “If I use the experience to make changes in people’s lives,” he says, “it’s worth doing.”