Composition of Fluorescent Lamp

Fluorescent lamp structure and role: fluorescent lamp at both ends have a lamp, the tube is filled with trace of argon and thin mercury vapor, the lamp wall coated with phosphor, the two filament gas conduction between the ultraviolet light, the phosphor Emits a soft visible light.

Fluorescent lamp features: When the lamp begins to ignite need a high voltage, the normal light-emitting only allow small current, then the voltage across the lamp voltage is lower than the supply voltage.

Fluorescent tube ends are equipped with filament, the glass tube wall coated with a layer of uniform thin phosphor, the tube was drawn into a vacuum 10-3-10-4 mm Hg later, filled with a small amount of inert gas, but also into a trace of liquid mercury. Inductance ballast is a core inductance coil, the inductance of the coil is the nature of the current changes, the coil will cause a change in magnetic flux, resulting in induced electromotive force, the direction of the current and the opposite direction, thus hindering The current changes.

Fluorescent Lamp Starter in the circuit from the switch, which consists of a neon discharge tube and a capacitor in parallel, the role of the capacitor to eliminate the electromagnetic interference with the power supply and the formation of oscillation circuit with the ballast to increase the starting pulse voltage amplitude. Discharge tube in an electrode with bimetal composition, the use of neon bulb discharge heating, so that bimetal in the opening and closing, causing the ballast current mutation and produce high-voltage pulse to the lamp at both ends.

When the fluorescent light into the circuit, the starter between the two electrodes began to glow discharge, the bimetal thermal expansion and contact with the static contact, so the power supply, ballast, filament and starters constitute a closed loop, current So that filament preheat, when the heating time of 1-3 seconds, the starter between the two electrodes glow discharge is extinguished, followed by cooling of the bimetal and the static contact is disconnected, when the two electrodes off the moment , The current in the circuit suddenly disappeared, so the ballast to produce a high-voltage pulse, it is superimposed with the power, added to the lamp at both ends, so that the lamp inert gas ionization caused by arc discharge, the normal light-emitting process, the town The self-inductance of the flow cell also serves to stabilize the current in the circuit.