Projector Lamp FAQ

Projector Lamp Anatomy

A projector lamp is made up of several components including the ARC tube, ultra-high pressurized mercury vapor, electrical wiring, a quartz globe or reflector, a fastener, a spoke, a bolt, a screw and finally the black plastic housing itself.

ARC Tube - The ARC tube is a piece of blown quartz measuring about 2 inches in length that protrudes up from the base of the quartz globe. The ARC tube is positioned by highly-accurate machines and then set with extra strength plaster.

Mercury Vapor - The mercury vapor inside most projector lamp ARC tubes is ultra-high pressurized. The mercury vapor is sensitive to the amount of current running through it and so projectors have electrical ballasts inside them to regulate electricity flow. The ballasts ignite the mercury vapor at a high voltage and then bring the voltage level down to the apropriate running voltage required to sustain the projector lamp.

Electrical Wiring - The electrical wiring on a projector lamp is fused inside the quartz ARC tube and runs out the top of the tube through the side of the reflector. Electricity from the projector and regulated by the ballast runs in a circuit from the back of the projector lamp through the side and back into the projector.

Quartz Globe - The quartz globe or reflector as it is sometimes called, is the hard exterior skeleton of a projector lamp. The quartz globe is usually lined with a highly reflective metal material on the inside that reflects light generated by the ignition of the mercury vapor inside the ARC tube. The quartz globe also holds the ARC tube in place and is usually filled with extra strength caulking in its base to complete this task.

Fasteners, spoke, bolt and screw - Projector lamps are connected to wiring that runs current to and from the projector. The wiring is attached to the projector lamp by way of a fastener, a spoke, a bolt and a screw.

The fastener is a small metal piece that is either glued, sodered or clamped onto the side of the projector lamp. The fastener receives the screw that in turn holds one of the wires in place against the fastener .

A spoke is connected to the ARC tube and is usually cemented in place at the back of the lamp. The spoke usually protudes about an inch and a half and receives the bolt which holds the second wire in place, enabling the projector lamp to complete the circuit.

Plastic Housing - The plastic housing is the piece of molded plastic that holds the projector lamp in place when it is sitting inside the projector. Projector lamps are usually locked into the plastic housing using a retaining clip. The attached wiring easily screws into a slot at the back of the plastic housing.

For more information about projector lamps, please do not hesitate to call or email us.