I know this thread is a schammer-
But for real, “photosynthesizing” lol a laser diode would be a horrible “unit” to use for horticulture lighting. I’ve been growing cannabis for over 10years now, and I’ve been building custom LED fixturz since I started in the industry. Using a unit like the OP, would probably kill the plants if not dialed in to correct PPFD levels.
1.) HEAT: Heat output would be way too much to deal with, unless using some select UV and far red and infrared diodes as supplemental lighting, which is already being done with LEDs.
2.) COSTS: the Samsung line of white diodes, which are organized
/labeled/sold via Kelvin measurements; (the LM301** diodes being the primary used diodes among the major manufacturers) typically used LEDs are 3500K, 4200K, 4500K, 5000K and sometimes 6500K, offer a large “full spectrum” bandwidth
as compared to any LD.. for example, a 3500k LED will have spectral readings from 380nm-700nm, peaking in the 550-650nm range. And as you increase Kelvin rates, the red portion of the spectrum decreases and the blue portion increases. Most manufacturers use 2-3 different white LEDs to produce a nice and full/dialed in light spectrum. Also something to note is the entire spectrum of white LEDs include small amounts of both UV-A and UV-B; 360-400nm.
Now having said that, and having built a shiz-ton of grow lights, I would definitely be Interesting in seeing the potential of using the UV, Far, Near and Infrared LD wavelengths.. the only issue would they would need reflectors to allow for a larger more even spread of the light intensity, but I wouldn’t be surprised if they showed increased yields for growers, especially making some supplemental light fixtures with just the fore-mentioned LD wavelengths. I would bet that they would provide better canopy penetration.. makes me want to build some up, if only I was still growing lol