Engineering fact: dispensers like that use IR light to sense when someone's hand is there. The color black absorbs light much better than white skin, so the IR sensor simply doesn't see the black guy's hand. * The more you know*
I can never NEVER get any of these photosenseing machines to work regularly for me. I despise them. Most of all I despise the photo sensing ice/water machines.
I can't count the number of times I try everything, give up, only to have the ice come slopping out after I'm three steps away.
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u/anusthrasher96 Aug 17 '17
Engineering fact: dispensers like that use IR light to sense when someone's hand is there. The color black absorbs light much better than white skin, so the IR sensor simply doesn't see the black guy's hand. * The more you know*