Flicker Free Fluorescent Lighting

By Eric Chen (http://iautistic.com)

Disclaimer: Please consult with a qualified electrician before using any of the advice below.

A common autism unfriendly feature is the common fluorescent lighting. While most people cannot see their flicker, some autistics do. It is irritating to have your room lit by high speed strobe lights.

Some people suggest using incandescent lamps. However, they use up much electricity, have a short shelf life and generate lots of heat. Some suggest buying very expensive lights that do not flicker, like [1, 2]. Using CFLs (compact fluorescent lamps) or switching to electronic ballasts may also help.

As an alternative, I suggest a system to make normal fluorescent lamps flicker-free.

		Use 3 phase current Our household AC (Alternating Current) electricity reverses itself 50 to 60 times per second, which causes flicker to occur. AC is actually transmitted to our homes, offices and factories using 3 phase current. These phases are exactly 1/3 out of phase with each other. This means that if you "combine" them together, they will cancel each other completely (refer to illustrations on the left). If we place 3 fluorescent tubes very close to each other, with each drawing power from a different phase, they will appear flicker free. Setting up the system Other than placing the tubes close together, we must also diffuse their light to ensure flicker cancellation. Placing some translucent plastic in front of the lamps can do. Alternatively, we can reflect light off a white or light colored surface (such as a wall). However, while many industrial and heavy duty equipment use 3 phase power, schools, offices and homes usually are usually wired with only 1 phase to save costs. To wire the 2 other phases into the lighting system may require a major overhaul and permission from the landlord and utility company.

Reference Materials

Last modified: Fri, 28 March 2008
Note: This may be only a minor modification (e.g. changing a spelling mistake)