Weeell, traditionally guitar fretboards stop at 21 or 22 frets because halfway along the string is where the first harmonic sounds, and if you put a pick-up there you get a full, rounded sound. There's no physical law stopping you from putting one there and many shredder-type guitars have 24 frets. The only practical reason for stopping around 22 is that the frets get stupidly close together. The 25th fret on this guitar will be 8mm from the previous fret which, if jumbo frets are used, gives you about 6mm to press down on. I was surprised this uses a relatively short scale length: if you really wanted to show off you'd use a longer scale length. A 28-inch baritone neck for example would allow you 28 frets before you hit the 8mm spacing.
Optical pickups are nothing new, and this "guitar" looks like it was made by special needs kids during a one-day workshop. Hoag, the inventor, invented these back in 1968 and first showed them at NAMM in 1969. As you can see, they're catching on.
Note that the actual bridge is under the pickup cover. That bit of rectangular metal you see below it is a name plate. Palm muting is almost impossible.
Also, external power is required for the light guitar... Less than optimal.
Having tried them, they work well. The tone is a bit sterile but clean.