Memorial Tributes: Volume 26
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  • LEROY (MIKE) M. FINGERSON (1932-2022)



    LEROY “MIKE” MALVIN FINGERSON was an internationally recognized authority in designing and developing the laser doppler velocimeter and particle image velocimetry systems for measuring details of flowing fluids. As founder and CEO he grew his small private company, TSI Inc., into a trusted leader of precision instruments that measure everything from fluid dynamics to aerosol biohazards. He passed away at the age of 89 on February 10, 2022, in Eden Prairie, Minnesota.

    He was born July 1, 1932, the son of Malvin and Corolla (née Sundet) Fingerson and raised on a small farm in a Norwegian-American community near Fountain, MN. The family had a strong commitment to education—his grandmother said that an education is something no one can take away from you. This is particularly poignant as this was during the Great Depression.

    Mike’s piano teacher encouraged him to leave the farm and go to the university. After running the farm for a year while his father recovered from a health issue, Mike set off in the fall of 1950 for Minneapolis and the University of Minnesota, where he earned a bachelor’s, master’s, and PhD in mechanical engineering. He was lucky to meet his future wife, Ruth Johnson, at a Lutheran student picnic—they literally bumped into each other, as they were playing volleyball and both going for the same hit. They were married November 26, 1960, at St. John’s Lutheran Church in Minneapolis.

    Mike invented a cool-film anemometer for his PhD dissertation, “A Heat Flux Probe for Transient Measurements in High-Temperature Gases,” which was the springboard to TSI (formerly Thermo-Systems Incorporated). Since this was well before the current era of venture capitalists, it was Ruth’s elementary school teaching salary that funded TSI in those early days. They penny pinched to get TSI off the ground—they drove an old car with a hole in the footwell that showed the road going past under their feet, and they stretched the groceries already in the cupboards for two weeks. And they shared their home with TSI, literally, as the company was in their basement with Mike’s four coworkers coming and going at all hours.

    The cool-film anemometer “worked fine,” but it was not a financial success. They subsequently marketed a series of hot-wire and hot-film probes, which became standard equipment in business, government, and university research labs.

    One of the authors, Gilmore Sem, joined TSI in 1967 and helped the company establish the aerosol instrument business by incorporating the patented technology of UMN professors Kenneth Whitby (NAE 1978) and tribute coauthors Benjamin Liu (NAE 1987), and David Pui (NAE 2016). The first project he worked on was the initial version of a product developed by Whitby, the electric Model 3000 Whitby Aerosol Analyzer. It was not a business success—TSI only sold 16 of them in 6½ years.

    During the 1972 California Aerosol Characterization Experiment (ACHEX, funded by the state Air Resources Board), Pui and Liu developed a miniaturized version of the electrical aerosol analyzer to measure size distributions of airborne particles smaller than 1 micrometer. William Wilson, a scientist at the Environmental Protection Agency, asked TSI to build three miniature electrical aerosol analyzers like the one Pui was operating. It was a difficult decision for TSI and Mike. The company’s sales manager and financial vice president were strongly against developing a second generation of a loser such as the Model 3000. One day in January 1973, Gil met Mike in his office to discuss Wilson’s request. The meeting lasted 75 minutes. They batted around the pros and cons of developing a second-generation instrument. Finally, Mike asked Gil how long it would take him to build three units for Wilson. Sem said about 18 months, with a cost of about $100,000. Wilson was willing to pay $50,000 for three. Mike calculated that TSI would lose $50,000 in the worst-case situation and said, “Let’s do it.”

    When TSI’s first Model 3030 Electrical Aerosol Analyzer was delivered to Wilson about 18 months later, the company had orders for 28 more from around the world and thus was assured of financial success. Mike had been willing to take a chance on the second-generation model even though the first-generation product was a failure. Without that decision, TSI would have gotten out of the aerosol instrument business. Instead, it is now considered the world’s leading company in aerosol generation, measuring, and sampling instruments.

    Sem appreciated that Mike left him pretty much to himself during most of his career. “As long as I was meeting goals that we had set together, he did not interfere much in my work.” That was Mike’s style with most of his staff. He chose dedicated employees and trusted them to make the right decisions. When the survival of the company was at stake, he was very much involved with survival issues, but for smaller decisions, he trusted his employees. When it came to ethics and interactions with colleagues and people outside TSI, Mike asked everyone to follow the golden rule: Treat others the way you want to be treated. His way of putting it was, “Conduct yourself so that, if the full facts were published on the front page of tomorrow’s newspaper, you would be proud of what you have done.”

    TSI continued to invent and patent products that are now sold around the world. When Mike retired in July 1998, the company had over 500 employees worldwide and more than $80 million in sales. Mike retired as president and CEO, having never received a promotion. Thirty-seven years is a long time to run a company, but that’s what Mike did, and he did it well.

    The intent was to provide tools needed in industry to make precise measurements in fluid mechanics and particle research. Three noteworthy products were 60 anemometers created for NASA in 1971, of which six went on to Mars, installed on the Viking spacecraft. In 1993 TSI’s single most successful product, the PortaCount Respirator Fit Tester, was launched, packaged for military use for the US Army and US Marines. And in 1995 TSI received its first contracts to develop and produce Ultraviolet Aerodynamic Particle Sizer instruments for the US Army and the Canadian Army. These instruments detect the presence of biohazardous materials in the air. For his overall technical innovations, he was elected to the National Academy of Engineering in 1993.

    Mike long credited the University of Minnesota for his successes in his career and life, and regularly turned to his alma mater to tap faculty researchers for help and advice—as his company grew, so too did its partnerships with the innovative engineers and scientists. As an expression of his appreciation, he was a longtime donor to the university and the Mechanical Engineering Department. Upon retirement he was honored with a gift that would ensure his legacy as well as the university’s ability to draw top talent: The LM Fingerson/TSI Inc. Chair in the Department of Mechanical Engineering was established in 1998 with a $1 million endowment.

    To Mike, the world was a place with endless possibilities. He was a pilot, a sailor, a skier, a man who could fix anything, a furniture builder, and a world traveler. He was a renaissance man, who loved the technical aspects of engineering, the challenges of business and leadership, and the depth of rich discussions in politics, literature, and philosophy.

    Mike and Ruth shared a marriage of love and adventure for over 61 years. They were members of University Lutheran Church of Hope for nearly 60 years, appreciating the community’s thoughtful, loving way of looking at our complex world.

    Mike was loved and cherished by many people. He is survived by Ruth, their children Mark (Robin), Karin Emerson (Rick), and Laura (John Pedersen), and four granddaughters.