Remembering the old star-shaped barcode scanner glasses at supermarket checkout lanes (advance, camera)

[Pink Jazz]

I am pretty sure many of us remember seeing the star-shaped barcode scanner glasses at supermarket checkout lanes. Most supermarkets have replaced them with newer checkout counters with rectangular barcode scanner glasses, leaving very few survivors.

Which leads me to my question: what exactly was the technical reason why the barcode scanner glass was star-shaped on older supermarket check-out counters? I understand the technology wasn't as advanced at the time, however, I would think there would be some technical reason why a star-shaped barcode scanner glass would be used.

[thecoalman]

I may be wrong here but as I understand it those models used a flat beam of light in a crisscross pattern, you only need one beam to read the code however it needed to be oriented correctly.

[harry chickpea]

IIRC, the idea was to not have to worry about the orientation of the product. The "best" scan was chosen. The optical sensor was "dumb" - not a camera or array of sensors but a single sensor (photoresistor?).