# REV Color Sensor V3
This sensor is emits light and then analyzes the reflected light that it sees. It is capable of measuring:
* raw distance up to 10cm (but most effective under 2cm)
* Alpha
* Hue
* Red
* Blue
* Green
Full Guide from REV Robotics:
Color Sensor Class Documentation:
Distance Sensor Class Documentation:
Supporting Images:
### Useful code:
Add your sensor object with the rest of your robot objects:
Hardware map it!:
Add some code like this to your main loop to read the values on your sensor:
Try something like this to drive until your sensor sees a red line:
```
while( color.red() < 100){
backLeft.setPower(.5);
backRight.setPower(.5);
frontLeft.setPower(.5);
frontRight.setPower(.5);
}
backLeft.setPower(0);
backRight.setPower(0);
frontLeft.setPower(0);
frontRight.setPower(0);
```
\*Note, this code is not intended to work right off the bat… this is just an idea of how you could use a color sensor to control your robot!\*
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