Why would this need to be a laser?
You could just use a broad spectrum tungsten lamp and then sweep across wavelengths with a prism or a grating to find the ideal visibility for whatever diagnostic you want (assuming there is such a wavelength), then see if there is a light source that emits that particular wavelength. Maybe it's an LED or it could be any type of lamp.
As much as I love lasers, they are not the most economical light source for just any application. If you don't care about the light being coherent, and you also need to focus the beam into a large area, then a laser would seem like an awful lot of increased expense and increased red tape.
You could just use a broad spectrum tungsten lamp and then sweep across wavelengths with a prism or a grating to find the ideal visibility for whatever diagnostic you want (assuming there is such a wavelength), then see if there is a light source that emits that particular wavelength. Maybe it's an LED or it could be any type of lamp.
As much as I love lasers, they are not the most economical light source for just any application. If you don't care about the light being coherent, and you also need to focus the beam into a large area, then a laser would seem like an awful lot of increased expense and increased red tape.