Two Source Laser Interference in 2D (Young's double slit experiment)

Demonstration of how I created a two dimensional interference pattern with a red laser.
Two double slits are arranged perpendicular to each other (one horizontal and the other vertical) to produce a grid-like arrangement of bright dots on a screen.
I did this as an experiment to make it easier for students to understand the interference pattern produced in the electron diffraction experiment. Until now I've only been able to draw upon their previous knowledge of two source interference in one dimension (Young's double slit experiment).
Relevant concepts: wave interference, coherent sources, and superposition.

[@julesm3576]

Well done. I was thinking to try the same thing. Glad you did this work and what fun science is!

[@PhysicsHQ]

Yeah it’s great. Well worth doing if you get the opportunity.

[@rustyosgood5667]

Any ideas about why the horizontal band is more pronounced? I assume the "dots" come from the shape of the source? Have you tried 2 perpendicular lasers (on the same plane)? Ideally of different colors and of the same color. It would be interesting to see if the perpendicular laser interferes and at what interval based on the frequency. It would also be interesting to see if a single beam (vs. split) can cause interference with another split source or single beam...if this makes sense.

[@PhysicsHQ]

Hi. The only reason I can think of for the prominence of the horizontal band is if I split horizontally before vertically. I’ve not tried separate lasers. That would be an interesting investigation. I wonder if phase difference would come into play 💭 . But even that would be an interesting factor!!

[@safwanakhtar2528]

Next try to find the eigen value of an inverted Möbius strip just like in marvel avengers endgame