I have a bunch of related questions so I will drop them all here:
* You mentioned focusing the spectrum on humans, but I have always wanted to have light that works well for both humans and plants (e.g. houseplants) as they are also beneficial for human spaces. Why not do both?
* Exposure to near IR has significant health benefits and seems like it should be included in an ideal lighting fixture that attempts to replicate the sun: https://pmc.ncbi.nlm.nih.gov/articles/PMC9855677/
What do you mean when you say IR can be produced in other ways more efficiently?
* How does your product compare with the Yuji Skyline?
For broadband IR, using a gas IR heater will give you the cheapest output - followed by an electric heater. Hard to compete with devices design specifically for heating when you are trying to do fancy optics in a compact form factor at the same time.
Yuji is similar to a lot of Chinese brands doing something similar which is a backlit Raileigh Scattering panel. The show images of the sun in their marketing and sharp sunbeams on the wall, but these are complete fiction. The also advertise color tuning, but the only natural color they can produce is a blue because Rayleigh Scattering doesn't allow very good color control. Still, for some applications like wall washing if you don't need a dynamic sky color and you can hide the view of the sun it could be a reasonable option.
We haven't researched plants a ton, but did some test to confirm they can grow under this light. Here is a cool time lapse video showing this in action: https://www.youtube.com/watch?v=2TDIVnXfE9I