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.
The film was initially set for release on June 15, 2012, but was later changed to June 22, 2012. On April 3, 2012, Pixar screened the first 30 minutes of the movie, and it received a positive reaction by its screeners.