how to read banknote of sensor? price<10$

Using Arduino Project Guidance
#1

how to read banknote of sensor? price<10$

:o :o

#2

Are you asking what kind of sensor to use to read bank notes? For what purpose? To distinguish one denomination from another? Or to distinguish a valid note from a counterfeit note?

For under $10?

#3

PaulS:
Are you asking what kind of sensor to use to read bank notes? For what purpose? To distinguish one denomination from another? Or to distinguish a valid note from a counterfeit note?

For under $10?

Value

#4

Camera and PC or Android phone, plus number recognition software.

#5