Defrosting of Automobile Windshields Using High Light Transmitting ElectroConducting Films

The development of a new high light transmitting electroconducting film for defrosting of car windshields is described. The film, called Hyviz, is deposited on glass by vacuum sputtering and consists of a complex of indium oxide and tin metal. This paper considers the electrical design of windshields, having films with electrical resistance between 10 and 20 Ω/square and supply voltages between 30 and 80 V. Data are given on defrosting with a Hyviz windshield at power levels between 0.3 and 1.0 W/in² (approximately 50-150 W/ft²) showing a defrosting time of about 5 min from 0°F for the higher power level.