Ultrasonic cleaning laser lens

[Pat PJ Johnson]

Would cleaning laser lens with ultrasonic cleaner work.

[Dan Hintz]

I would suggest against it. First, cleaning agents are often water-based, and the anti-reflective coatings are hygroscopic... not a good combination. You also run the risk of beating up the AR coating by scratching it with the debris (though to be fair, if you're at the point where you need to use an ultrasonic cleaner to get it clean, your lens is probably shot).

[Rodne Gold]

Not only what dan said , but US cleaners work by cavitation , exploding bubbles remove dirt and also erode the surface of hard materials = not good for a lens.