We developed and put into the market clocks with luminescent hands by EL (electroluminescence) for the first time in the world. The EL especially developed for alarm clock is approximately 1.6 mm in width of luminescence. It is also for the first time that such a narrow width EL was developed. Several kinds of new technology were developed in parallel for the clocks with EL hands. The following three items are main points in this development: (1) Miniature rotary contact with high reliability was developed for the supply of electric power, (2) Inverter circuit driven by dry battery was developed for the excitation of EL, and (3) Factor of life span of miniature EL applied to clock hands was investigated and improved.
