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From: wtm@neoucom.UUCP (Bill Mayhew)
Newsgroups: misc.consumers,sci.electronics
Subject: Re: fluorescent lights and my brain
Summary: The lights blink 120 times / second
Keywords: eyes head ache electricity
Message-ID: <1143@neoucom.UUCP>
Date: 27 Apr 88 19:10:27 GMT
References: <530@scourge> <1182@ssc.UUCP> <1532@dataio.Data-IO.COM>
Organization: Northeastern Ohio Universities College of Medicine
Lines: 19


We connected a photo cell up to the input of an oscilloscope just
to be sure.  It would appear that fluorescent lights flash 120
times per second.  That is to say, one pulse of light is emitted
for each 1/2 cycle excursion of the 60 Hz waveform.

Phasing of the power leads to the lights would probably be pretty
much irrelevent.  (Even if lights in adjacent rows were phased
oppositely.)

What would help would be to obtain a solid state ballast unit as is
used in recreational vehicles.  The ballasts operate at high
frequencies, thus the flashing is less objectionable.
Unfortunaely, some people find the several KHz whine just as
annoying as the 120 buzz emitted by conventional lighting.

Ce est la vie.

--Bill