X-Ray Spex came about in 1964 when Harold von Braunhut (the mastermind behind Sea Monkeys) repackaged an optical effect made popular by a device called the Wonder Tube.
Advertised in American comics, X-Ray Spex appeared to be a technological marvel.
Despite only costing a few dollars they enabled you to see the bones in your hand, the lead in a pencil, the yolk of an egg and other “blushingly funny” amazing things – which adolescent boys all over the world took to mean just one thing . . . they could be used to see through girls’ clothing!
It was, sadly, all tosh. The glasses were cheap plastic things with cardboard lenses. Each lens had a small hole in it, and across this hole was a white bird feather.
When you looked through the vanes of the feather you saw two offset images – a darker one inside and a lighter one outside -as light was refracted through the feather.
So, for example, when you looked at your hand through the specs you saw what appeared to be bones.
Sadly, when used in the playground, you simply saw through the claims in the advert and realised you’d wasted a week’s pocket money to look like a gullible pervert.
Eventually, the manufacturers discontinued the use of plastic frames and began producing X-Ray Spex entirely out of cardstock.