发明授权
US3551725A Method of tipping-off the exhaust tube of an electric lamp,and a baseless single-ended incandescent lamp produced by such method 失效
电动排气管的拆卸方法,以及通过这种方法生产的无源单端不良灯泡

Method of tipping-off the exhaust tube of an electric lamp,and a baseless single-ended incandescent lamp produced by such method
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