Integrated HID reflector lamp with HID arc tube in a pressed glass reflector retained in a shell housing a ballast

An integrated, high frequency metal halide reflector lamp, comprising:

• a) a sealed reflector unit comprising
• a reflector envelope comprising a pressed glass reflector body having a basal portion, a parabolic reflector surface extending from said basal portion and terminating at a circumferential rim of said reflector body, a light reflective material on said reflector surface, said reflector surface having an optical axis and a focus on said optical axis, and a light transmissive lens hermetically sealed to said rim of said reflector body,
• a metal halide discharge device comprising a discharge vessel of ceramic material enclosing a discharge space, an ionizable fill comprising mercury, a metal halide and a rare gas within said discharge space, a pair of discharge electrodes within said discharge space and between which a discharge is maintained during lamp operation, and a respective current conductor extending from each discharge electrode to the exterior of said discharge vessel in a gas-tight manner, said discharge device having a major axis, said discharge device being positioned with said major axis transverse to said optical axis and with said discharge space between said electrodes coinciding with said optical axis, and
• b) a shell of synthetic resin material having a circumferential rim portion receiving said rim of said reflector body and a base portion for receiving a lamp base, said shell generally tapering from said rim portion towards said base portion;
• c) a lamp base on said base portion of said shell and having a pair of lamp contacts;
• and
• d) a ballast within said shell between said sealed reflector unit and said lamp base for energizing said discharge lamp to maintain a gas discharge between said discharge electrodes,
• during normal lamp operation said discharge device being free of acoustic resonances at alternating lamp currents below a lowest lamp resonant frequency, and
• the ballast circuit energizes the discharge lamp so as to have an alternating lamp current having a fundamental frequency and harmonics which are integral multiples of the fundamental frequency,
• the fundamental frequency and the lowest lamp resonant frequency are greater than about 19 kHz, and
• the harmonics above the lowest lamp resonant frequency have amplitudes which are insufficient to induce acoustic resonance.

A reflector lamp comprising a light source energizeable for emitting light, a reflector body having a reflective surface for directing light emitted by said light source, and a lamp base having lamp contacts electrically connected to a light source capsule, characterized in that:

• said light source is a high pressure gas discharge device, and
• the lamp further comprises
• a pressed glass lamp envelope sealed in a gas tight manner and enclosing the high pressure gas discharge device, the pressed glass lamp envelope including said reflector body having said reflective surface,
• (i) a shell having a first end portion carrying said lamp base and a second end portion receiving said lamp envelope;
• (ii) a ballast for energizing said discharge device to emit light, said ballast being mounted within said shell between said pressed glass lamp envelope and said first end portion, said ballast including a pair of input terminals each electrically connected to a respective contact on said lamp base and a pair of output terminals each electrically connected to a respective one of said current conductors of said discharge device;
• and
• (iii) said lamp envelope being received at said second end portion with said reflective surface positioned to reflect light and heat generated by said discharge device away from said ballast.