Infrared Light sensing with PIC16F877

[emufambirwi]

In scenario where I am supposed to detemine if two rectangular planar objects are aligned exactly, I decide to use an infrared led and phototransistor on each of two diagonally opposite corners on the two rectangular objects.

what will be effect of the width of the beam on the resulting signal into the PIC?


Will it not show alignement before fully aligning?

 

[DJ_ReL@X!]

The phototransistor won't give you a 5 V output. So you may want to use a comparator and adjust it to give 5 V when the objects are fully aligned.

You could use an external LM311 or one of the comparators included in 16F877A.