Arduino - Photo Resistor Example - KY-018

About: Hello world! I make simple & Advanced projects for people who want to learn programming and electronics. Most of my Instructables are about arduino and the wide range of sensors you can use with it. I ma...

Hello World!

I made another example for one of my sensors. Now we are using the KY-018 Photoresistor Sensor as a switch

to turn on light when shining some light on it, in the video i turn the light on with a laser, a flashlight, a candle, and a lighter, it doesnt matter what kind of light you use.

See the next step for the Schematic Code & parts list.

Step 1: Schematic Code & Parts List.

Parts List.

  1. Arduino uno, I used the RobotDyn Uno.
  2. KY-019 1 channel Relay
  3. 1 Led of any color. I used blue.(Don't really need this)
  4. KY-018 Photoresistor sensor.
  5. Lamp + socket and power cable (optional) You can an add any device!

Good luck!



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    2 Discussions


    2 years ago

    nice and simple project!! can we use ky-009(3 color led module) as a led/lamp? pls answer, i'll add auto light switch in my robot :D thank you,..

    1 reply

    Reply 2 years ago

    if we can, how to connect the pin? and what code i must change? i'm new in arduino, but i'll try to make an useful robot, i've visit this web every day for learning, but it's my first comment, i hope u'll answer it, thank you :)