IAEEL newsletter 3-4/97
Pears on Philips´ menu
Pears on Philips´ menu
CFLs hidden behind an envelope that looks like a normal incandescent GLS lamp are nothing new, but up until now only smaller manufacturers have produced them. Philips´ new GLS-like CFL could be the start of a new trend. Osram is reported to follow soon.
Disguising a CFL within an envelope is not so easy: The first problem is that the envelope increases the lamp temperature; thus special precautions must be taken to avoid a significant drop in lumen output (A similar drop can, of course, occur if the lamp is used at high ambient temperatures). Philips has solved this problem by using amalgam technology. Although this helps control the vapor pressure, the lamp´s start-up time will be longer.
The second problem with an envelope is that some light will be lost. Philips claims that they have managed to trim losses down to approx. 5.5 percent, which is much lower than the 1015 percent typical of CFLs with an outer envelope.
The lamp was launched in late 1997. Color rendering is around 80, and the correlated color temperature is 2 700K, closely matching that of a standard GLS lamp. The lamps come in 5, 9, and 11 W, and are 132 mm long, with a bulb width of 65 mm and a base width of 48 mm, whereas a standard GLS-lamp is 106 mm long, 60 mm wide and significantly more narrow at the base.
However, the lamp only has a rated life of 56 000 hours, compared with 10 000 for a standard, quality CFL. This fact is disguised by the information provided on the package that the lamp will last for 5 years under normal residential use.
The current retail price in Germany is about DEM 20 (~US$1012).