Is it possible to salvage a fingerprint scanner from an old and dead smartphone and use it with Arduino? I am not talking about writing an android program and send data to Arduino over Bluetooth or WiFi, I am talking about wiring up fingerprint scanner of a mobile phone to Arduino.
Long-shot, but if the phone is still functional enough to unlock with a fingerprint, try sensing the overall screen brightness when locked and when unlocked, and use that as the "Fingerprint matched" signal. Obviously this won't work with a truly dead phone.
A lot of processing goes into reading and storing or matching a finger-print. The magic is in the software, not (only in) the sensor. An Arduino (Uno class or similar) is way under-powered for the task. Perhaps one of the Arm- or other high-end Arduinos would have the capability if you had or could write the necessary software.
Short answer: No.
Possible but not directly as the arduino compatible fingerprint sensor contains image formation and saving mechanism which means that those sensors scan a fingerprint form image and send the scan status not the finger print image....
As in case of fingerprint sensor of phones, the sensor directly send the whole image...
so you have to use FPGA (Field Programming Gate Arrays) to make communication between that...
But this is a very expensive way... As FPGA are very expensive but have huge functionality means you can design any circuit any sensor any controller you want using FPGA
In general: It depends. We can only talk about the general situation, not about details, because we don't know the exact sensor type. You are facing some serious problems when doing this.
- Without a part number or something like this, we cannot say, how the sensor communicates with the phones mainboard. It might or might not be a communication interface, that the Arduino has or can be made capable of.
- The sensor and it's interface might be proprietary, which would mean, that there is no public documentation about the interface and how it works. Reverse Engineering something like this need mostly a big amount of time and experience with various electronical systems.
- As Shyam Singla already pointed out in his/her answer, most (if not all) Arduino compatible fingerprint sensors don't send the actual fingerprint image, but do the difficult image handling and recognition by themselves. The Arduino only get's status information (for example if a previously saved fingerprint was detected). On a phone, this is most likely not the case. The main processor of the phone has way enough power to do the calculation by itself. It doesn't need to offload them to an external chip like the Arduino needs to. (Also this gives the vendor the opportunity to update the recognition software later on with a simple OS update.) That means, that the sensor will most likely only send images and you would need to do the image handling and recognition on the Arduino. AVR based Arduinos (like the Uno or Nano) are totally undersized for this.
- The connection pins of the sensor will be very small and difficult to connect, especially if you are a beginner.
- You would have to use level shifters and voltage regulators to interface between the 5V devices Uno/Nano and the sensor, which will most likely work with a significantly lower voltage (at max 3.3V, most likely less).
Using FPGAs to tackle some of these problems is possible, but also very challening. If you need to ask this question, this is most likely out of scope. (A friend of mine did program a FPGA for his physics master on university. It can be very difficult.)
All in all I would say, it is not worth the effort to even try this. Instead buy an Arduino compatible fingerprint sensor.