The "Zenith Flash-Matic" remote control, invented by Eugene Polley, another engineer at Zenith, was the first wireless remote control, replacing the signal cable based remote control devices, which never were a success. The Flash-Matic used directional flashlight in the transmitter device, and photo cells in the television set itself. One of the major shortcomings of this technology was that if the television set was exposed to direct sunlight, it could inadvertently trigger one of the remote control functions. The company president sent the engineers back to the drawing board to come up with a better solution.