Arnold Beckman

A Caltech chemistry professor, Beckman was asked in 1934 by a citrus processor why its acidity measurements kept failing. He built a sturdy, portable acidity meter with a vacuum-tube amplifier, the pH meter, and realised every laboratory would want one. Beckman Instruments followed, and later the DU spectrophotometer, which turned slow chemical analysis into a quick reading. It is a textbook case of an expert listening to one customer's problem and spotting the much bigger market.