How Does it Work?
The human eye tends to notice brighter colours over darker colours. The printed one way vision film contains areas of printed graphic (a print pattern) as well as unprinted see-through areas covering up to 50% of the film. The holes, where there is no film, have no ink and therefore are generally darker, almost black.
When someone during the day looks at the window from the outside, their eye is drawn to the printed image, as it reflects more light than the see-through areas, which looks like it is on a solid piece of vinyl. However, when viewed from the inside, a person will see the outside world through the holes. The secret here is ensuring the printed graphics are hidden from the other side of the glass. This is best achieved by having a black ‘backing’ that covers only the printed areas on the film, without blocking the unprinted areas.