Little light with Distance Captor

Hi everyone,
this is my first post here, hope my thread will captive you

I m a beginner in electronic stuff and use to be "one day" a JAVA developper
I'm working on a small robot gadget i try to teach about distance and color.

I want a "base", placed in position A, this position is fixe.
My gadget, can move to the right and to the left from my captor.
First step :
- when the gadget go to the right of the captor, a BLUE light will turn ON.
- when the gadget go to the left of the captor, a REDlight will turn ON.

Second step : Include distance captor.
- when the gadget go to the right of the captor,
-- from a distance between 0cm and 20cm = light OFF
-- from a distance from 20cm and more = light ON



What kind of captor can i use in my "base" and my gadget to spread and get the signal to switch on/off the light ?

Thanks for you help !!
primobobi

Welcome.

Have a look at this it might do the job:
https://www.ebay.co.uk/itm/TCS230-T...m=282725977417&_trksid=p2045573.c100505.m3226

If your using an arduino check arduino playground there may well be a library for it.

Thx dr Pepper !
'll check that