The best replacement for ir sensor is pir sensor.

The best alternatives to ir sensor are rated as following:
★★★★★  pir sensor

Your alternative for ir sensor is not listed? Suggest!
Speaking about ir sensor, one probably shouldn't forget about arduino.

Other search terms related to ir sensor and their ratings are:
★★★★★ arduino
★★ pic16f877a
★ lm324
You have in mind a companion for ir sensor and it is not yet here? Propose!



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ir sensor
pir sensor