For questions about Deflectors, devices used on Starships in Star Trek: Manipulatable energy forcefield or shield that can be generated around space vessels and other facilities for protection from natural hazards and enemy weaponry. Always use in conjunction with the [star-trek] tag.
In The Outrageous Okana, it is described that lasers are ineffective against the Enterprise:
WORF: Still no response. Captain, they are now locking lasers on us.
WORF: Yes, sir.