Philips Infraphil PAR38F and PAR38E heat lamp
Around 1980 the pressed glass heat lamp
13379F was replaced by a modernised
version, the PAR38F. A few years later
the bayonet sockets of the Infraphil
armatures were replaced by E27 screw
sockets which had been common for
normal incandescent lamps since the
early 1920s. The E stood for Edison, the
original inventor of the system and 27
was the diameter of the screw in
millimeters. The corresponding Infraphil
lamp with an E27 screw base received
type number PAR38E. The print on the
PAR-lamps was of the type C version with the three Philips shield emblems, the
operation voltage, the wattage (150W), the type number, a production code, the
country of origin and both the trademark Philips and brand name Infraphil. There were
PAR38E heat lamps where the brand name Infraphil was replaced by the code IR but
these were heat lamps for general heating purposes. PAR38E lamps without reflector
and Fresnel lens also existed but these were for illumination purposes only and not
suitable for medical applications.