| 摘要 |
<p>An incandescent lamp, which emits infra-red radiation, comprises a tubular quartz envelope, within which a tungsten filament is supported. To reflect radiation, which is emitted in a downward direction from the filament, back in an upward direction to an item to be heated, a substantially pure aluminium oxide coating is bonded in a substantially permanent manner to the surface of the envelope. The coating extends substantially along the length of the lamp and around approximately half of the cross-sectional circumference thereof. The coating is applied to the envelope by a spray gun technique, wherein finely divided aluminium powder is blown through an oxygenated flame, which is directed towards an area of the envelope to be coated.</p> |
