Abstract: An edge lighting system has a plurality of light sources, such as light emitting diodes (LEDs) mounted at spaced-apart intervals along a rail that is disposed adjacent to an edge of a display surface. Orifices formed in the rail in which the light sources are inserted are sized to enable each light source to move freely into contact with the edge of the display surface when urged by a force provided by a compressed elastomeric member to provide a uniform illumination as the light is internally reflected in the material comprising the display surface. The light sources extend beyond a concave (parabolic) surface on the rail that reflects light from the light sources into the edge. Any object approaching the display surface is illuminated by the light being conveyed within the material.

Abstract: A marking carried by a physical object and discernible by an infrared (IR) sensor is at least partially concealed from the human eye. The marking is covered with a coating that is at least partially opaque in the visible spectrum and at least partially transparent in the IR spectrum (or other non-visible spectrum). The marking is thus not apparent to a human eye or to visible light sensors, while remaining discernible in the IR spectrum. Using the present invention to prevent a user from detecting the marking adds intrigue to the detection of the object, since the workings of the IR sensor that enable the sensor to identify the marking are not evident to a user. The present invention is also beneficially employed in games where it is desirable that an opponent be unable to see a marking that is detectable by the IR sensor.