Prior art is of huge importance to the open-hardware movement. It prevents that certain markets become locked for 20 years by patent law.

Let's generate some prior art with patents. I claim all the claims generated by rewriting all patents in the world which use the concept of scanning mirror and do not mention the concept of scanning prism. I make these claims by rewriting the scanning mirror patent but now using the concept of scanning prism. I think these new claims would be obvious for a Person Having Ordinary Skill in the Art (PHOSITA), familiar with my work and familiar with the patent. The total of these claims and other prior art describe the legal application limits of transparent polygon scanning.

Let's provide some examples;

Example 1: US7892474

This is an interesting patent it describes something like Continuous 3D printing. Could explain why Carbon didn't outline the figure 3 option.

Claim 1 reads  "... comprising the step of solidifying a photo-polymerizable material by means of mask exposure of a build area or partial build area in a building plane via electromagnetic radiation from a digital light processing/digital micromirror device projection system ..."

using transparent prism creates prior art not under patent let's reformulate

"... comprising the step of solidifying a photo-polymerizable material by means of refraction exposure of a build area or partial build area in a building plane via electromagnetic radiation from a transparent polygon scanner device projection system ..."

Example 2: US9079355B2

The first reflective polygon scanner in photo-polymerization was described by the Institute of Physical and Chemical Research (RIKEN) in 1997. 
RIKEN did, however, not describe the combination of a laser diode and reflective polygon scanner.
Shuji Nakamura of Nichia discribed the blue diode laser in 1996.  Envisitontec patented the combination of polygon scanner, laser diode and 3D printing in 2011. This was a smart legal move.

Claim 1 reads:

 "... and deactivatable ultraviolet laser diode and a rotating polygonal mirror ..." 

using transparent prism creates prior art not under patent let's reformulate

" ... and deactivatable ultraviolet laser diode and a tranparent polygon scanner ..."

Example 3:  EP3233499B1

Laser induced forward transfer can be used to generate droplets with laser light. The earliest description I could find date back to 2004.
Poeitis patented this process for bio-printing in 2015. In this video, it is describes how laser-assisted bioprinting works.  The process is also shown in figure 1 and 2 of the patent.
From the video it can be concluded that a transparent polygon scanner can be used to shoot with a laser pulse on a disk so a droplet is emitted. This can be used in bioprinting, 3D printing or used in the semiconductor industry to deposit resist,  glue, polymer or ink etc.
A microfluidic chips with multiple channels could be made and the transparent polygon could be used to send a laser pulse to the disk and  select the channel from which the droplet is emitted.

Example 4:  US900887
Compact, low dispersion, and low aberration optics scanning system. I claim the same in this patent but then with a moving transparent prism.

Example 5: US6850363
Arthur Ashkin, nobel laureate, invented the optical tweezer with Gerard Monrou and Donna Strickland.
This patent describes optical tweezer in a laser scanning microscope using a scanning mirror. I claim an optical tweezer made by a scanning transparent prism or galvo transparent prism.