Definition of "optics"

Digging deeper, the invention of eyeglasses is an elaboration of the more fundamental development of optics technology. The ability of a segment of a glass sphere to magnify whatever is placed before it was known around the year 1000, when the spherical segment was called a reading stone, […] .

2013 September-October, Henry Petroski, “The Evolution of Eyeglasses”, in American Scientist‎

[…] I'd be interested to know whether US authorities proffered any "advice" on the optics: Ixnay on the torture dungeon, […] ; if you have to have victims' loved ones present, go for the widows and photogenic orphans rather than Moqtada's boys.

2007 January 1, Mark Steyn, “Blowing a 'hinge moment' of history”, in The Jerusalem Post‎

When President Obama responded to the failed Christmas airliner bombing while on vacation in his native state of Hawaii, some Republicans claimed it was “bad optics.” “Hawaii to many Americans seems like a foreign place,” the Republican strategist Kevin Madden told CNN.

2010 March 4, Ben Zimmer, “Optics”, in The New York Times‎

"There's also a gentle nod to the Vatican and Italy, which shows the Pope is not above playing a little optics - I'm sure he and the CEO of Fiat have met."

2015 September 28, Vanessa Barford, quoting Dan Neil, “Pope Francis and the little black car”, in BBC News‎

“The optics weren’t good. Next time tell them not to bring guns”

2021 February 9, David D. Kirkpatrick, Mike McIntire, quoting Mike Shirkey, “‘Its Own Domestic Army’: How the G.O.P. Allied Itself With Militants”, in The New York Times‎