Visible light LEDs are produced having a layer of conjugated polymer which is cast directly from solution or formed as a gel-processed admixture with a carrier polymer. The first position is set to such a position that a distance between a mounting surface of the expansion device and the antenna when the housing is placed on the mounting surface in the vertical orientation and a distance between the mounting surface and the antenna when the housing is placed on the mounting surface in the horizontal orientation are equal to each other. In one example, the portion of light is reflected back to the light detector.