Tim Shearon wrote:
> It would seem to be a vibratory frequency that there would not be
> natural occurances of and thus our visual system isn't prepared, so to
> speak, for what the jiggling means. i.e., it is a combination of the
> resonance of the LEDs (a pretty slow refresh rate) and the speed at which
> the visual system "updates" incoming information.
>
The only kind of LED (light-emitting diode) I know about is a DC device and
doesn't have a refresh rate -- it stays on. It sounds like you're talking about
a CRT (?)
Using an elbow-powered toothbrush, I've not seen the jiggle under discussion,
but the fact that it happens with both digital clocks and televisions seems
important. If you put an oscillating magnetic field near a CRT the whole screen
will jiggle at 60Hz. But an LED can't jiggle; there's nowhere for it to go. It
could pulse, but the point is that it can't do what the tv can do, which
suggests that either there are two mechanisms that create the same perceived
jiggle, or that the perceived jiggle depends on something either common to or
independent of both devices.
(How) do we know that the toothbrush is affecting the clock/tv rather than the
perceiver?
Original question:
> >Does anyone here know why it is that the numbers on a digital clock (and
> >some images on a television screen) appear to jiggle when a person is
> >using an electric toothbrush?
> >
--------------------------------------------------------------------------------------
Ben Miller
Dept. of Psychology
Salem State College
[EMAIL PROTECTED]
