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A comment on Two ways to use an LED as a light sensor with Arduino. Parent comment

Re:Two ways to use an LED as a light sensor with Arduino by anfractuosity on Thursday June 20, 2024 @01:18PM (#40741016)
Have you come across https://en.wikipedia.org/wiki/Quartz_crystal_microbalance re. the piezoelectric effect, you can apparently measure very small masses.

(It sounds like you do need to apply an alternating current for this though)

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Re:Two ways to use an LED as a light sensor with Arduino by antirez on Friday June 21, 2024 @05:58AM (#40747925)
Cool. Yep, piezos only produce current while the mechanical stress changes its shape, but if the load is stable, no current is performed, so I guess that's the reason why you need to apply an alternating current to it in order to use it that way. Thanks.
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