The drawback to LED based night vision illumination systems is that they are not really useable at distances of more than 100 feet no matter how many LEDs you use in the array. Filter based night vision illuminators that change visible light into infrared light are capable for much greater distances, but they suffer from huge energy losses due to massive heating of the filter material and because of this, require massive amounts of current and are only suitable for outdoor use. A laser on the other hand, is capable of extremely long distance illumination and is probably the most energy efficient source of bright light possible.
The main problem with using infrared lasers to create night vision illuminations systems is that there are safety issues that must be addressed, especially when using lasers with a rating higher than Class IIIa, or lasers that have an output power of more than 5mW (milliwatts). Class IIIb and Class IV lasers can output as much as 500 mW, and they are certainly not eye safe, especially when highly focused. A laser that outputs only 50 mW may seem like nothing, but be aware that instant eye damage could occur if you hit your retina with a focused beam. Using infrared lasers makes this situation so much more dangerous because you cannot see the beam, and your blink reflex will not help save your vision in the event of an accidental exposure to the laser beam.
Do not continue with any of these experiments unless you are well aware of the dangers involved and have proper laser safety equipment and experience in using higher powered lasers. You can still create a useable short range laser illuminator using a lower power 5mW infrared laser diode or module, so consider starting with a Class IIIa laser if you want to experiment with laser night vision illumination.