| 摘要 |
PCT No. PCT/EP92/00684 Sec. 371 Date Dec. 8, 1993 Sec. 102(e) Date Dec. 8, 1993 PCT Filed Mar. 27, 1992 PCT Pub. No. WO92/18805 PCT Pub. Date Oct. 29, 1992.A lamp cover in particular for fluorescent lamps consists of a light-transmitting material which at least on one surface features a structure which affects the rays of light that penetrate the material. The present lamp cover is to achieve a soft-focus effect, i.e. light-impervious elements located in the ray path should not be recognizable from the outside. In addition, the lamp cover should have a light-directing effect whereby in the polar diagram in terms of inensity the direction of the light beam hitting the structure in essence has the same direction as the light beam exiting the structure whereby the exiting light beam features a ray expansion. At least on one side of the lamp cover, the surface features a wavelike structure whereby this wavelike structure stretches perpendicularly to the longitudinal axis of the lamp cover and the number of wave trains is in the neighborhood of at least three, preferably ten and maximum a thousand per lamp width, and whereby the wave trains are constantly changing curves whereby these curves are either sine curves or constantly changing radius curves. |
