One way vision film is a vinyl with tiny holes or a micro perforated mesh applied to a transparent surface. The film contains areas of printed graphic as well as unprinted see-through areas. These see-through areas are small holes that are too tiny and closely spaced to affect image quality while printing. There are a wide variety of grades, for example 80:20 has 80% material and 20% hole.
How it works is that the eye focuses on light reflecting from the printed colors of the graphic rather than light passing through the perforations. The other side of the film is usually black to create a one-way effect.
So when a person is standing on the outside, his mind registers the overall image and not the tiny holes, but when is standing on the inside (facing the black side of the material), the eye is focused on gathering details from within the holes.
See-through graphics can also be printed onto transparent non-perforated surfaces. This is achieved by printing layers of dot or line patterns on top of each other in exact registration or with minimum overlap.
One thing that you should keep in mind when you are using this type of material is the illumination.
The level of illumination on either side on the window is important to ensure the best effect. One way vision is most effective during day time, as sun light is brighter than inside lights.
The application of this material its unlimited. The graphic can be applied to glass or other transparent panels to provide advertising, branding and one-way privacy. Another of the most popular applications is the building wraps, converting buildings into advertising billboards while providing privacy and solar control benefits to those inside without blocking their outside view.