PROJECTION LAMP WITH A WIRE SCREEN FOR BLACKENING PREVENTION

1,184,704. Electric incandescent lamps. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 1 June, 1967 [4 June, 1966], No. 25267/67. Heading H1F. A projector lamp is combined with an elliptical mirror and has a filament 6 arranged at the focus of the mirror and surrounded by a wire screen 11. The mirror may be outside or inside the lamp or, as shown, may take the form of a cold-light coating 15 on an ellipsoidal portion 3-4-3 of the bulb 2. The opposite side of the bulb may be of spherical form and have a reflective coating with a window 5-5. The screen, which prevents blackening of the bulb, consists of a plurality of wire loops 12 attached to a pair of stay wires 13 and is supported, through insulating glass beads 14, by the leadin wires 8. The filament 6 is in the form of a flattened coil which is less than 5 mm. from the screen.