Energy-saving lamp has an internal IR reflective coating

摘要

An energy-saving lamp has a bulb which is internally coated with an IR reflective film and which has a double-parabolic shape surrounding a linear incandescent wire or a linear arc discharge tube. In an energy-saving lamp with a bulb comprising a lens and a reflector which are joined together around a linear incandescent wire or a linear arc discharge tube, the novelty is that: (a) the lens and reflector have parabolic interior surfaces; (b) an IR reflective film is applied onto the interior surfaces; (c) the incandescent wire or arc discharge tube is aligned w.r.t. an axis which connects the apices of the lens and the reflector; (d) the reflection focal point of the lens coincides with that of the reflector or is located on the axis at a smaller distance from the apex of the reflector than the reflection focal point of the reflector; and (e) the incandescent wire or the arc discharge tube is located between the reflection focal point of the reflector and the apex of the reflector. Preferred Features: The IR reflective film comprises several TiO2 and SiO2 films or several Ta2O5 and SiO2 films. Alternatively, the IR reflective film on the reflector consists of aluminum or silver. The lamp is designed as an incandescent lamp, halogen lamp, high or low pressure sodium lamp, metal-halide lamp or xenon lamp.