There's some history to laser availability, but right now, it's because you can make all those readily available colors from a light emitting diode. LED's are the same way where the only available yellows use phosphorescence to convert blue to yellow, which you can't do for a laser, and doesn't work all that well comparatively. If someone invents a yellow diode, they will get very, very rich because it is something the biomedical field needs as well as for displays and lighting.
ohtochooseaname t1_j7gr2fg wrote
Reply to Why are green and red laser pointers so cheap and available, but yellow ones not so much? by SurprisedPotato
There's some history to laser availability, but right now, it's because you can make all those readily available colors from a light emitting diode. LED's are the same way where the only available yellows use phosphorescence to convert blue to yellow, which you can't do for a laser, and doesn't work all that well comparatively. If someone invents a yellow diode, they will get very, very rich because it is something the biomedical field needs as well as for displays and lighting.