Angus Macleod, SPIE fellow, Professor Emeritus of Optical Sciences at the University of Arizona, and founder of the Thin Film Center, died on 29 April at the age of 87. He will be missed by all his friends and colleagues in optics.

Angus’ contributions to thin-film modeling and production are well known, and his books and software are legendary in the industry. Angus was very helpful and kind to us in Zemax, especially during the late nineties when we were adding polarization and thin-film capabilities to what would become OpticStudio. His code was the benchmark we tested against and his advice in producing efficient, accurate algorithms was priceless.

What was maybe less well-appreciated was Angus’ scope as an optical physicist. In an optical physics code like OpticStudio, you must never lose sight of the question: what is the right answer? That may not always be an easy question to answer for something as complex as the optical systems modeled by OpticStudio. On several occasions when Ken, Sanjay and I didn’t know or couldn’t agree on what the right answer was, Angus played the role of Supreme Court judge. Listening patiently to alternate views and asking probing questions, he would then deliver his verdict in a typically modest style.

What always struck me about Angus in those situations was how simply he reframed the question and how physical his answers were. Angus was more than capable of all the mathematics of optical physics, but he always spoke in terms of basic physical processes. Einstein’s dictum of "Keep it as simple as possible, but no simpler" was perfectly evident in Angus’ thinking.

So farewell then, Angus MacLeod, and thank you.

Author:

Dr. Mark Nicolson
Emeritus CEO
Zemax