The laser linewidth is determined by the quality factor of the resonator, the higher the quality factor of the cavity, the narrower the laser linewidth. After considering the gain of the laser medium, the theoretical limit of the linewidth of the laser is determined by the spontaneous radiation of the gain medium.

Do not be directly targeted by any laser beam under any circumstances!Care should also be taken to prevent the laser beam from reflecting into the eye.Therefore, it is necessary to wear laser protective goggles when laser work, in order to reduce the instantaneous accidental or chronic laser damage to glasses.