Abstract: A method of applying a protective light-transmitting coating on the exterior surface of the glass envelope of a lamp, the method comprising: holding the lamp with its longitudinal axis disposed horizontally and rotating the lamp about its longitudinal axis; flow-dispensing a liquid coating material of a predetermined viscosity onto the rotating lamp envelope from a dispensing means including a profiled row of needles located above the lamp; and allowing the envelope coating to be cure-hardened, such as by irradiation. The method is particularly useful for applying an optically clear photopolymer coating on the glass envelope of a photoflash lamp in less than one second and then curing the coating by irradiation with a source of ultraviolet light.