Introduction: Laser Diode Module Tutorial


This 100mW laser module emits a small intense focused beam of visible red light. The module can be used with an Arduino and photo resistor module to perform basic remote signaling.

Warning: This is a low power laser device, however as with all laser devices care should be taken when in use. You should never look directly in to its beam or point the laser at another person. Doing so may cause permanent eye damage. This item is not suitable for children.


Input voltage: 5V DC

Input current: 30mA

Wavelength: 650nm

Step 1: Materials Preparation

In this tutorial, we will show you how the Laser Diode Module works with Arduino together. The materials needed are listed as below:

  1. Arduino Uno
  2. Female to male jumper wire
  3. USB Cable Type A to B

Step 2: Hardware Installation

Diagram above shows the Laser Diode Module pinout, which contains Signal (labeled as S), GND (labeled as -) and the middle pin indicates +5V. The connection between Laser Diode Module and Arduino Uno is described in detailed way as below:

  1. Signal -> Pin 8
  2. GND -> GND
  3. +5V -> 5V

Step 3: Source Code

  1. Download the source code attached here and open it via Arduino software or IDE.
  2. Choose the correct board and port before uploading the code into the board.
  3. Upload the source code into Arduino Uno.

Step 4: Results

From the source code, "delay (1000)" means that the duration goes for 1 second. Both "digitalWrite (LaserPin, HIGH)" and "digitalWrite (LaserPin, LOW)" indicates when the input voltage is high or low, which light up or fade out the Laser Diode respectively. The expected outcome should be:

  1. The Laser Diode light up for 1 second.
  2. The Laser Diode fade out for 1 second.
  3. Repeat the 2 steps above until stop supplying the voltage into Laser Diode Module.