Abstract: A photoelectric sensor array apparatus and method, relates to at least two photoelectric rail elements each having alternating light emitting diode transmitters and photo detecting receivers. The array produces a plurality of light devices with corresponding sensors, whereby the light beams are blocked in the region where an opaque object is located. Each rail contains both transmitters and receivers so that control circuits for the transmitters and receivers are substantially identical and mounted on opposite sides of the array apparatus, to provide a more compact unit of higher resolution and to reduce the design and manufacturing costs. Such construction and method enable the sensing array apparatus to function in direct sunlight or other such photoelectric saturation conditions, which would otherwise blind conventional light sensitive sensor arrays.