The increased inter-layer bonding using laser scanners has my attention.
Materialise filed for patent in 2015, WO2016049621A1. It abandoned the application.
Siemens, the owners of Hackaday, filed for  (WO2018188757A1), where they take into account correction parameters by looking at the previous layer. It seems not directly related.
There are many more HP,   Epson US11498266B2 etc.

I view patents as the Sport of Kings.  Given my experience, I decided to
create prior art. There are downsides, but less costs upfront.

Previously, I outlined that the laser line is orthogonal to the direction of the last extruded line.
A possible challenge, is that the laser line does not cover all possible motions of travel.
It should be obvious for a PHOSITA, that with a single line immediately after the extruder your direction of movement is limited to 180 degrees with an orthogonal scan line.

I therefore claim the following;
   two laser lines are projected to cover both sides, depending upon the motion one would
   heat up after extrusion and the other prior. Or one side would heat up both prior and after
   extrusion.

In additive manufacturing it is often beneficial, to execute the printing process at an elevated temperature via for example a heated build chamber.
This creates problems as lasers and electric motors function better at a low temperature.

I therefore claim the following;
  the PCB board which forms the basis of the laser prism scanner is placed on top
  of a thermoelectric (TEC) cooler. This cools down the side of the laser and the PCB
  motor. It heats up the side which is in contact with the heated build chamber.

Earlier, I outlined that a combination of two cylindrical lenses can be used to reduce the cross scan error distortion and create a circular spot.
It might be beneficial to elongate the laser bundle orthogonal to the scan line.
As this increases the area which is heated, whilst still using one laser or led.

I therefore claim the following;
     a cylindrical lens or other lens is used after the prism which elongates the laser / led bundle
     orthogonal to the prism.  This is done to increase the area that is exposed by the optical bundle.

One could use a plurality of emitters but I doubt that the heating process has to be so accurate.
It should be noted that the quartz prism and lenses can be made of another plastic material i.e. acrylic given its low absorption in the infrared range.
This has the advantage that costs would drop.

As such, I claim the following;
   The infrared emitter is a light emitting diode, all optical elements for the scanner are manufactured
   using acrylics.

The control system would need to use data to optimize the heating process.
I imagine that an infrared sensor or camera is present that collects the light emitted from the heated area.
It might be possible to collect this information in the laser scanner using the laser microscope configuration outlined earlier. The information is than used to optimize the image formed by the laser or led scanner.  Epson claimed this in US11498266B2, however it outlines that information of a temperature sensor is used for the nozzle heater.

As such, I claim the following;

   I claim that a temperature sensor is used with the relation outlined by Epson.
   but that this is used to control the settings of the lasers and not the nozzle heater as outlined by
   Epson.

It might be beneficial to use multiple wavelengths.  The extruder could extrude a thermoplastric material in combination with a resin. In these cases, it might be beneficial to combine the infrared laser with a UV laser.