Optical Imaging Touch Screen Technology

Optical imaging is a relatively new touch screen technology that is very quickly expanding its fan base because of the scalability and versatility it offers. It is especially feasible for large units or devices. It works by two cameras sharing a field of view. From two different viewpoints, an image silhouette can be created. In this case, a shadow casted by the object creates the image.

This touch screen technology is unlike others in that it can even recognize the size of the object touching the screen. This is because it uses an infrared backlight and image sensors along the screen sides. When an image touches the screen it casts a shadow and two image sensors can triangulate the position of the object that touches the screen as well as the size of the object based on the shadow the object casts.