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A comment on Ultrathin business card runs a fluid simulation. Parent comment

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Re:Ultrathin business card runs a fluid simulation by hturan on Saturday August 09, 2025 @05:18AM (#44845132)
I might be wrong, but you might need need (at least) a 23x23 LED matrix to have a white border around the outside to give it the contrast needed (the "quiet zone", since QR data is black).
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Re:Ultrathin business card runs a fluid simulation by phirks on Saturday August 09, 2025 @07:20PM (#44851287)
This is why my first prototype had a white border around it. The LEDs were red back then, so I don't know exactly what I was thinking, but I was aware of the problem.

https://github.com/Nicholas-L-Johnson/flip-card/blob/main/me...

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