Now a days with fairly inexpensive micro controllers available and much easier to use (compared to the old school way),
a nice representation can be built.
The "eye" itself is wide, gliding from side to side giving the impression it is mechanical.
The entire set of 5 LEDs are not blinking (on/off) as it travels.
When the leading LED goes on, the trailing one goes off so it "moves" smoothly across the eye slot, bounces off the end and returns again.
Many years ago, I made mine using a micro controller from Parallax BS2-IC (Arduino is the way to go these days).
My helmet was made to be worn with the light (never have worn it as a costume).
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Will be interested is seeing your finished result.
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