Light Sensor

Introduction

The Light Sensor measures the brightness of light reflected from or shining on an object. It outputs an analog value that represents how much light is detected.

This page uses light_sensor as the example Light Sensor name. Replace it with your own configured name as needed.

Below is a list of available methods:

• brightness – Returns the amount of light detected by the Light Sensor as a percent.

• changed – Registers a function to be called whenever the Light Sensor’s brightness value changes.

Constructor – Manually initialize a Light Sensor.

• Light – Create a Light Sensor.

brightness

brightness returns the amount of light detected by the Light Sensor as an integer. This can be used to check if an object is bright enough to accurately report other visual data.

Usage:
light_sensor.brightness(units)

Parameter	Description
units	Optional. The unit to return the brightness with: PERCENT (default).

changed

changed registers a function to be called whenever the Light Sensor’s brightness value changes.

Usage:
light_sensor.changed(callback, arg)

Parameters	Description
callback	A previously defined function that executes when the Light Sensor’s brightness value changes.
arg	Optional. A tuple containing arguments to pass to the callback function. See Functions with Parameters for more information.

def my_function():
  brain.screen.print("Brightness changed")

# Call my_function whenever the brightness changes
light_sensor.changed(my_function)

Constructor

Constructors are used to manually create Light objects, which are necessary for configuring a Light Sensor outside of VEXcode.

Light

Light creates a Light Sensor.

Usage:
Light(port)

Parameter	Description
port	The 3-Wire Port that the Light Sensor is connected to: On the V5 Brain – brain.three_wire_port.x where x is the number of the port. On a 3-Wire Expander – expander.a where expander is the name of the expander instance.

# Create a Light Sensor in Port A
light_sensor = Light(brain.three_wire_port.a)