Automatic Beam Blocker

A beam blocker (BB), also known as "beam shutter", is a device used to block / unblock a light beam while the source power stays on.

Here I present a way to implement an extremely cheap and simple Automatic Beam Blocker (ABB) that can be used to block a low power laser beam.

The beam blocker is composed of a shutter that is open or closed by pressing a push button connected to an Arduino Uno board.

Materials

• 3D printed beam blocker (STL files available on Thingiverse repository)
• Servo motor (Tower Pro SG90 9G Mini servo)
• Push-button
• 1 Kohm resistor
• Connection cables
• Arduino UNO board

Implementation

To build the beam blocker, first, download and print the files automatic_beam_blocker_1of2.STL and automatic_beam_blocker_2of2.STL. Afterwards, mount the pieces according to the figure.

In principle the Automatic Beam Blocker requires only a 1/2" optical post to be mounted on any experiment. Notice, however, that the component is compatible with Thorlabs cage system. I also provide a SCAD file (automatic_beam_blocker.SCAD) that allows to change different parameters in order to make the ABB compatible with cage systems from other manufacturers.

For more information on the circuit implementation and the Arduino code, visit the page in my blog dedicated to the automatic beam blocker.

Once the beam blocker is assembled, mount the circuit, upload file beam_blocker.ino in the Arduino UNO, and start using the Automatic Beam Blocker in your experiment!