Build a Michelson Interferometer in Minutes with OpenUC2

Introduction

In the age of Raspberry Pi and Arduino, electronics projects have become accessible to everyone. Yet, optics and advanced experiments like interferometry often remain somewhat closed-source mostly due to their missing availability. What if you could build a Michelson interferometer (the experiment that told us we are not leaving in the ether and measures the speed of light!!) using modular components and just a few simple tools? That’s where OpenUC2 comes in: a modular optical toolbox designed to make experiments in optics as approachable as building circuits with a breadboard.

In this tutorial, we’ll show you how to create a Michelson Interferometer using OpenUC2’s modular cube system. By the end, you’ll not only visualize interference patterns but also understand how this setup can measure tiny changes, like surface roughness, with remarkable precision.

What is a Michelson Interferometer?

The Michelson Interferometer splits a light beam into two paths using a beam splitter. The beams reflect off mirrors, reunite, and interfere constructively or destructively depending on the path difference. These interference patterns reveal precise changes—down to nanometers—in alignment, surface angles, or displacements.

With OpenUC2, the complexity of such setups disappears. Instead of expensive and bulky optical benches, we use 3D-printed cubes, kinematic mirror holders, and accessible electronics.

Why OpenUC2?

OpenUC2 (“You-See-Too”) is a modular platform inspired by open-source principles, much like the Lego of optics. Here’s why it’s ideal for learning and tinkering:

Modular: Build, adjust, and reconfigure optical setups easily.

Affordable: Leverages 3D-printed and off-the-shelf components.

Expandable: Add components like cameras, motors, or LEDs to enhance functionality.

Open-Source: Everything—from CAD files to software—is openly available.

Materials Needed

We make an exception and skip the step of printing the parts and buy the ready-to-use OpenUC2 Discovery Interferometer Kit and start right away. This includes cubes, mirror holders, and beam splitter mount and most importantly, the 520nm laser pointer. Some additional information:

• Link to the kit and instructions
• Product link

Optional Add-ons:

Translational stage for fine mirror adjustment

Camera module for capturing interference patterns

The kit contains:

• Laser diode
• Hikrobot Camera (MV-CE060-10UC) with USB cable (Hikrobot Camera Software installation)
• Stage with gear with mirror
• Three kinematic mirrors (in cubes)
• Beam splitter in cube
• Sample holder (in cube)
• One empty cube
• 16 base plates
• Screen
• Pinhole in cube
• Screwdriver to adjust alignment (1, 5x60)

Diagram: ​

Instructions for assembling the Michelson's Interferometer: ​

Step 1: Build a four base plate

Build a four base plate as shown. This will be used to connect the laser diode, pinhole, the beamsplitter, and an empty cube. Add the base plates to fix them.

Note: At this point the laser diode should be turned off the whole time. Don't look at the laser directly. Always use screens to look for the laser light.

Step 2: Place the pinhole

Place the pinhole such that it is as far as possible to the laser diode.

Step 3: Close the diaphragm

Close the diaphragm as much as possible to end up with a small hole.

Step 4: Place the screen and align the laser

Place the screen after the pinhole and turn the laser on. The alignment is most likely off. So to align the laser you should use the screwdriver and adjust the laser mount screws so that the beam is centered on the pinhole. Turn the laser off.

Step 5: Replace the pinhole with a kinematic mirror

Without touching the screws of the laser, remove the pinhole from the group of cubes and add a kinematic mirror instead.

Step 6: Align the beam with the pinhole

Using the top and bottom base plates, place the pinhole after the beamsplitter connecting the pinhole and the kinematic mirror in a straight line. Place the screen after the pinhole, turn the laser on and align the beam to the center of the pinhole as shown. Turn the laser off.

Step 7: Set the Michelson interferometer arms

Remove the pinhole and set other base plates as shown. These are the variable and reference arms of the Michelson interferometer. Place the reference and movable mirrors as shown. Place the pinhole in the detection spot. Fix everything with base plates.

Step 8: Align and observe the interference

Place the screen after the pinhole, turn the laser on. You will see two beam spots, one from each mirror. Adjust the movable mirror angles with the screwdriver so that you can see an improvement in brightness of one of the spots and look for the maximum.

Step 9: Adjust the reference mirror

Adjust the screws of the reference mirror so that the two beams overlap as much as possible.

Step 10: Observe the interference pattern

Remove the pinhole and place the screen only. You will see two extended beams. Adjust the reference mirror screws to overlap the beams perfectly. You will see the interference pattern emerging. Then try to center the pattern on the screen. Turn the laser off.

Step 11: Set up the camera

Place the camera and fix it with the base plates. Connect it to the computer and open the MV Software. To check the MVS tutorial click (here).

Step 12: Adjust the camera exposure

Adjust the exposure time of the camera. You should see a fringe pattern. Try to adjust the reference mirror screws finely to bring the center of the interference pattern to the center of the camera.

Experimental Data ​

This is the fully assembled UC2 interferometer with a green laser diode, a camera representing a scree and to digitize the inteference, a beamsplitter, a kinematic mirror and a mirror that can be translated along Z.

If you bring the two beams on top of each other, you will be able to observe the interference pattern, which in case of one beam exactly overlaying the other will be a ring pattern. These rings are also called Newton rings and come from the fact that we interfere two divergent beams, leading to a super position of two spherical caps/waves.

Using the ESP32 camera, we can quantify the motion of the beams and e.g. measure distances or angles.

Conclusion ​

Congratulations! You have successfully built a Michelson Interferometer using the UC2 modular microscope toolbox. This device allows you to explore the interference properties of light and perform fascinating experiments. As you move one of the arms, you will observe constructive and destructive interference patterns on the camera, demonstrating the wave-like nature of light. Have fun experimenting with different setups and learning more about the wave-particle duality of light!