Abstract: An electronic device may be provided with a display. The display may have a display cover layer. The display may have an active area with pixels and an inactive area without pixels. An opaque masking layer such as a layer of black ink may be formed on the underside of the display cover layer in the inactive area. Windows may be formed from openings in the opaque masking layer. Optical components such as infrared-light-based optical components may be aligned with the windows. The windows may include coatings in the openings that block visible light while transmitting infrared light. The window coatings may be formed from polymer layers containing pigments, polymer layers containing dyes that are coated with antireflection layers, thin-film interference filters formed from stacks of thin-film layers, or other coating structures.

Abstract: Using nano-particles to topographically enhance the reacting surface of an inorganic fiber used as a reinforcement medium in an embedding matrix is described.