You can read a history of Angénieux here
Nouveau logo, c'est le cadeau que s'est fait cette semaine Angénieux à l'occasion de ses 75 ans. Retour sur les succès et les faits marquants qui ont fait d
optronique.net
The founder of the company simplified the computation of lenses, which allowed him to create more complex designs. Pierre Angénieux received two Academy Awards, which I guess means his products were well known.
As I recall, Angénieux perfected the zoom, and his consumer department later got snapped up by the Japanese, maybe Tamron, when the big SLR zoom fashion hit. They were also I believe a very appreciated supplier of remote sensing optics at a time when there were basically two nation-state customers for such things, and of course binoculars for various military and law enforcement purposes. I think their expertise in binoculars can still be found in some military nightvision, rangefinders or aiming devices under the Thalés brand, eg the nightvision optics used by Rafale fighter pilots or french army helicopter pilots.
http://optronique.net/defense/systeme/jumelles-dhelicopteres-helie.
One will occasionally see used Craigslist type ads for their small roof binoculars eg 8x24, which I think were issued as "Dienstglass" to law enforcement, their original 35mm still camera zooms which were much appreciated, quite a number of 16mm and 35mm cine lenses, and also I seem to recall that a considerable number of ancient Kodak camera sold in France had Angénieux lenses due to some strange customs rules.
In summary Angénieux was a french optics brand that got pushed to the high end like most European manufacturers, and then disappeared/merged.
Edmund