Demystifying the Ferrocell: Specular Reflection

in MES Science2 months ago

In my previous posts I had posted about the amazing visualizations and geometry present in a ferrocell as well as several possible explanations as to what causes the unique holographic colored lines. Recently, however, the YouTuber AB science may very well have cracked the actual explanation, which is specular reflection.

Recap that the ferrocell comprises the following:

  • 2 thin glass sheet with a 10 um gap.
  • Nano-sized ferromagnetic particles mixed in with a lubricating oil.

Previous theories about what the lines represent included the magnetic field lines or magnetic field isopotential lines. However, those don't actually describe most of the colored lines observed in real life. On the other hand, specular reflection provides very accurate simulations for many, if not most, effects of the ferrocell.


The above image compares the ferrocell lines with light sources spread all around the cell vs. a simulation modeling the specular reflection off the nanoparticles as they align along the magnetic field of the permanent magnets. The ferrocell and simulation match up very well.

Note that the simulation on above appears to have the light sources a bit misplaced. Here is another example but with the magnetic pole perpendicular to the ferrocell.


The same software can be used to predict the ferrocell geometry of very complex configurations, such as this comparison between the simulation (left) and the 12 magnets configuration (bottom right).


Image source:
Note that the top right (a) image is the magnetic isopotentials or lines of equal magnetic field strength.

Specular Reflection

Specular reflection is just simply the phenomenon that occurs when incoming light reflects such that the angle of incidence is the same as the angle of reflection and as illustrated in the image below.


Looking in the mirror is an example of specular reflection.

Diffuse Reflection

In real life, however, not every surface acts as a perfect specular reflector, thus there will be some diffuse reflection. The incoming light may be scattered across many different angles besides just the specular reflection angle.


The ferrocell is predominantly specular reflection but some diffuse reflection is to be expected.

Ferrocell Tutorial Videos

Lori Gardi aka Fractal Woman goes over several tutorials illustrating the concept of specular reflection and the simulation modeling of the ferrocell.

Demystifying the Ferrocell: Parts 1 to 3

Part 1:

What the Ferrocell Shows

The Ferrocell: Demystifying the Misconceptions

Demystifying Reflection and Scattering (and the Ferrocell Once and for All)

Ferrocell and Simulation Videos

Here are several videos comparing the ferrocell real life optical geometry with that of the specular reflection simulations.