Skull. 3D printed quasi-holography

The continuation of my optical searches - 3D printed “holographic” images, which arise due to a slight displacement of the linear structure. Although we see the relief, the object itself, unlike lithophany, has no protrusions and dents. I call it "flat sculpture". When you tilt a shape or light source, the image appears and disappears, its shapes light up or darken.
Everything is printed without post-processing with one material on an FDM or SLA printer.
The image is best seen in contrasting backdrop material or in lighting from the top or bottom of the back.

Photos do not convey the effect well, it is better to watch the video:

You can also see the head of Darth Vader made on this principle https://www.prusaprinters.org/prints/31527-darth-vader-3d-printed-quasi-holography

And head of David: https://www.prusaprinters.org/prints/31544-david-3d-printed-quasi-holography

For the convenience of turning the figure, I used a rotating table, which can be downloaded here: https://www.prusaprinters.org/prints/31458-motorized-mini-turntable

Print instructions

Model size 100x63 mm, but I printed about 80 percent of the real size. Nozzle 0.4 fits well, but other sizes can be chosen. With an increase in overall dimensions, the thickness (in this case, depth) can be increased to a lesser extent, in my experience 4 mm is quite enough.
In my experience, it is possible to print in light colors, transparent gives less effect, like black. The presented model is printed in white plastic.