Do I need an additional fingerprint sensor?

Question

Sensors

There is a fingerprint scanner gtm-5110c31 .
To scan a fingerprint, you need to perform 3 functions:

1. Turn on backlight - just turns on the backlight
   
2. Check if finger is applied - returns whether the finger is applied or not
   
3. Scan fingerprint - scans the fingerprint and checks it against the database
   

The essence of the question is whether it is possible to turn on the backlight and, using the function of checking that the finger is attached, wait for the finger, for example, if this sensor is used in a smart lock, then it can wait tens of hours, in the documentation (attached above), I did not find anything about it.
Perhaps someone has already worked with similar modules and knows?
Or do I need to put an additional proximity sensor and only when the finger approaches, turn on the backlight and check?