Abstract: One embodiment may take the form of a method of operating a computing device in a reduced power state and collecting a first set of data from at least one sensor. Based on the first set of data, the computing device determines a probability that an object is within a threshold distance of the computing device and, if so, the device activates at least one secondary sensor to collect a second set of data. Based on the second set of data, the device determines if the object is a person. If it is a person, a position of the person relative to the computing device is determined and the computing device changes its state based on the position of the person. If the object is not a person, the computing device remains in a reduced power state.

Abstract: The underside of an inactive portion of a display cover layer in an electronic device may be covered with an opaque masking material. Openings in the opaque masking material may be form ambient light sensor and proximity sensor windows. An ambient light sensor window may be filled with a material that transmits at least some visible light. A proximity sensor window may be filled with a material that transmits more infrared light relative to visible light than the material in the ambient light sensor window. The materials in the ambient light sensor window and proximity sensor window may include one or more layers of ink, patterns of holes, layers of material that are shared with the opaque masking layer, and materials that are black, white, or other colors. A light guide structure may be used to route light received from a sensor window to an associated sensor.