An implementation of a system, device and method for projecting a visual indicator against a surface is provided. A display projection system in a handheld sensor device (e.g. a handheld wall scanner) projects a static or computer-controlled dynamic pattern of light onto a surface being scanned to indicate a specific feature, such as existence of solid structures of wood, metal or plastic, electric or magnetic fields, or a disturbance of a field. The projected light may be controlled by a computer via an aperture to allow flexibility in what is projected, such as icons, lines, graphics, characters and colors.