A leak detection method and apparatus is characterized by the production of analog signals representative of the fluid inlet flow and fluid outlet flow of a closed or open system. A light-emitting device 91 having the light-emitting element is covered with an upper shield plate 93 and a lower shield plate 94 each provided by a conductive metal plate while being held between the plates. The tire inflation monitoring system includes a control receiving at least one input from at least one tire pressure sensor sensing pressure of at least one vehicle tire. As a result, an SRAM that is typically scrapped as a result of non-functional tag subarrays can, instead, be recovered for sale and subsequent use. Each adjustable light absorbing filter is adjustable to a substantially transparent state, and the pixel-generating element generates a viewable pixel having a color adjustable between substantially a color of the light source and a color of the light source as modified by one or both of the adjustable light absorbing filters.