In general, the longer the wavelength, the deeper it penetrates into tissues.
UVAI—400 nmArgon—488–514 nm KTP—532 nmDye—585–600 nmRuby—630 nmAlexandrite—755 nmDiode—810 nmNd:YAG—1,064/1,320 nmEr:YAG—2,940 nmCO2—10,600 nm