Sometimes Steven Case would study the photos of employees on the wall at the business he founded, CyberOptics Corp., trying to remember their names.

By the time the company's ranks had grown past 100, he had to stop. "Still, he tried," said longtime colleague and friend Jim Leger, an engineering professor at the University of Minnesota. "Making connections with people was so important to Steve."

Case, a much-admired professor, engineer, entrepreneur and executive, died Tuesday evening when the small plane he was flying crashed while landing at the Crystal Airport. He was 60.

At the airport on Wednesday, the only visible remains of Case's SR22 aircraft was a lone tire, and federal investigators were reconstructing the tragedy.

They said the air-traffic control crew, which normally closes the tower at 10 p.m., planned to wait until Case landed. Around 10:02 p.m. the tower crew watched Case's single-engine Cirrus plane appear to land on runway 14L-32R. The crew closed the tower, confident Case had landed safely, as he had many times before.

Then, through the pouring rain, they saw flames, according to Pamela Sullivan, an investigator for the National Transportation Safety Board (NTSB). Case "just missed'' the north-south runway, crashing about 100 feet to the east, said Crystal Police Sgt. Rob Erkenbrack.

Case, the only person in the plane, was dead, the plane destroyed.

"When they last saw him they believed he was fine,'' said Sullivan, who arrived at the scene at noon Wednesday.

Case, flying in from Mankato, was familiar with the airport and the plane, she said. "He was a private instrument-rated pilot who routinely flew in and out of this airport.'' Now, it will be at least six months before the investigation is completed, and it's uncertain whether investigators will ever know what exactly happened.

Colleagues and friends universally described Case not only as a brilliant scientist and engineer with formidable intellectual gifts, but as a "gentle soul.''

"He was a very kind man," said Jeffrey Bertelsen, chief financial officer for the Golden Valley-based company.

While a professor of electrical engineering at the University of Minnesota, Case developed a system of laser-based sensors used as a quality control tool by circuit board manufacturers. In 1984, CyberOptics was spun out of the university into a private company. "It was a beautiful transition from university lab to what became a substantial company," Leger said.

CyberOptics is now publicly traded with $45 million in annual revenue and 150 employees working in Singapore, Shanghai, the United Kingdom and Oregon, in addition to its Twin Cities headquarters.

Case served as CyberOptics' president until 1998 and became the company's chairman in 1995, a title he retained up to his death.

While Case built his business, he continued an affiliation with the U's Institute of Technology, serving for many years as an adjunct professor.

"Engineering can be quite dry," Leger said. "But Steve's classes were very popular. He'd come to class with a pocket full of what he called 'feelies' -- fiber optics, modulators, detectors. He'd pass them around so the students could see and feel what he was talking about."

At CyberOptics, he was known for holding company-wide parties for employees, updating them on company news.

Beyond business, Case had a passion for photography, often creating dramatic black-and-white prints reminiscent of those of photographer Ansel Adams. One of his favorite locations for taking photos was Yosemite National Park, an Adams favorite. For many years, Case had a darkroom in his St. Louis Park home but was an early and enthusiastic convert to digital photography. His work decorated the board room at CyberOptics' Golden Valley headquarters, and sometimes he would give prints to friends as gifts.

Management experts said Wednesday that the loss of a founding executive can be a terrible blow for a small business. When a tragedy strikes a small company, the surviving top manager must immediately acknowledge the deceased to employees, otherwise bitterness might set in, said Dr. David Vang, a finance professor at the University of St. Thomas who has written a book on entrepreneurship.

"You try to emphasize the good aspects of the past, and acknowledge the accomplishments that will continue in the future," Vang said.

At 10:25 a.m. Wednesday, CyberOptics sent out a news release. In it, CEO Kathleen Iverson called Case "a wonderful friend and colleague to everyone who worked with him. He established a strong and capable management team, and we will do what Steve would want, and that is to continue to aggressively pursue the ideas and promising opportunities he set in motion."

Case is survived by his wife, Beverly Caruso, and two grown daughters. Funeral arrangements are pending.

Janet Moore • 612-673-7752 Paul Levy • 612-673-4419