The refractive index of current eyeglass lens materials ranges from 1.498 (CR-39 plastic) to 1.74 (a specific variety of high-index plastic). So for the same prescription power and lens design, a lens made of CR-39 plastic will be the thickest lens available, and a 1.74 high-index plastic lens will be the thinnest.
Principal photography on the film began on April 25, 2016, in Pittsburgh, Pennsylvania, in the Hill District, and wrapped in mid-June 2016. Fences was released in the United States on December 16, 2016, by Paramount Pictures, received positive reviews and grossed $64 million.
Fences trailer: Denzel Washington and Viola Davis face off in Oscar-tipped film. A charged adaptation of August Wilsonâs Pulitzer prize-winning play about a dysfunctional family dynamic is being pushed as an awards contender. This article is 7 months old. Tuesday 27 September 2016 10.40 EDT Last modified on Monday 27 February 2017 04.05 EST.