Disclosed are various embodiments of a holographic based optical touchscreen and methods of configuring such devices. In certain embodiments, a touchscreen assembly can include a holographic layer configured to receive incident light and turn it into a selected direction to be transmitted through a light guide. The holographic layer can be configured to accept incident light within an acceptance range and so that the selected direction is within some range of directions so as to allow determination of incidence location based on detection of the turned light. A light source can be provided so that light from the source scatters from an object such as a fingertip near the holographic layer and becomes the incident light. Thus the determined incidence location can represent presence of the fingertip at or near the incidence location, thereby providing touchscreen functionality. Non-limiting examples of design considerations and variations are disclosed.