Tuesday, June 2, 2015

Metrology: You Should All Just Leave Now

By Geoff Walker

Dr. Edward F. Kelley (KELTEK, LLC) is one of the world’s top experts on display metrology. He spent 31 years at NIST (National Institute of Standards and Technology), where in 1992 he started the NIST Flat Panel Display Laboratory. Ed was the obvious best candidate to teach the Monday Seminar on Display Metrology.

Yet about two minutes before the Seminar started, he told the audience that they should all just leave now because they would be bored, and because he had too many slides (172 – that’s one slide every 30 seconds!). Only one person in the audience actually left, saying “You convinced me!” as he walked out.  The fact that 99% of the audience stayed is a testament to Ed’s reputation and knowledge.

Ed is somewhat of a character. He identified himself to the audience as a “redneck metrologist” – although it wasn’t clear that everyone in the audience really understood the term “redneck”. Ed uses a cartoon character as a kind of avatar; here are two examples from his website:




Ed told the audience that he created the seminar by selecting slides from the 700-slide deck that he uses to teach a three-day course on Display Metrology. He said that it took several passes to get the selection down to only 172 slides. Given that preamble, it’s clear that this was no ordinary seminar. It was like drinking from a fire hose. From my perspective as a knowledgeable display person (but certainly not a display metrologist), I estimate that I understood about 25% of the material. Even so, it was a treat listening to Ed dispense wisdom gained over 40 years.

One simple example is when he was describing measuring zero-luminance black (slide 71). He said that just because you can’t measure it doesn’t mean that it’s actually zero. You must sit in the dark for at least 30 to 45 minutes with the display set to zero-luminance black while avoiding ALL source of light – including LEDs. If after that time you can’t see any light whatsoever coming from the display, then you truly do have a zero-luminance black, which implies infinite contrast.

Ed forcibly stated that if you have any serious interest in display metrology, then you must obtain the IDMS (Information Display Measurements Standard). It can be downloaded as a free 51 MB PDF from www.icdm-sid.org, or purchased as a 563-page printed book for $130.


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