Abstract: An optical film includes a substrate and a reflecting layer. The substrate has a sensing surface and an opposite back surface. The reflecting layer is disposed on the sensing surface of the substrate to reflect a sensing light and includes a coding pattern, wherein the coding pattern is formed by damaging a structure of the reflecting layer, and the coding pattern includes a coding information. The above-mentioned coding pattern of the optical film is a depressed structure, which can reduce the wear caused by the repeated writing of an optical reading device. A user input system including the above-mentioned optical film is disclosed as well.

Abstract: An optical film includes a substrate, a scattering layer, a coding pattern and a coating layer. The substrate has a sensing surface and an opposite back surface. The scattering layer is disposed on at least one of the sensing surface and the back surface of the substrate to scatter a sensing light. The coding pattern is disposed on the scattering layer to reflect the sensing light, wherein the coding pattern includes coded information. The coating layer covers the scattering layer and the coding pattern. The coding pattern of the optical film is able to diffusely reflect the sensing light, so that an optical reader device may obtain a uniform image of the coding pattern.

Abstract: An optical film includes a substrate, an absorption pattern and a scattering reflection layer. The substrate has a contact surface and a back surface opposite the contact surface, wherein the substrate allows a first light to pass and is made of a non-rigid material. The absorption pattern is arranged on the contact surface of the substrate to absorb the first light. The scattering reflection layer is arranged on the back surface of the substrate to scatter and reflect the first light to the contact surface of the substrate. The foregoing optical film enables an optical reader device to detect variations of the reflected first light, which is caused by deformation of the substrate, so that the corresponding force information can be obtained. A user input system including the foregoing optical film is also disclosed.