if you reflect a lazer will it loose some of its energy?

Question: if you reflect a lazer will it loose some of its energy?
- Keywords:
  energy,
  reflect
Asked by funkypigeondotcom to Mike, Pip, Tianfu, Tim, Tom on 28 Jun 2012.
- Tom Lister answered on 28 Jun 2012:
  
  Some of the energy will be absorbed by the mirror, and small amounts will scatter off in different directions on even the smoothest mirror. Polished metal mirrors can be pretty efficient though, and not much energy is lost.
- Tim Stephens answered on 28 Jun 2012:
  
  What Tom said, but there are also things called ‘dielectric mirrors’ which are made up of very thin layers of material stacked onto a glass plate. They can be very nearly 100% efficient.

Question: if you reflect a lazer will it loose some of its energy?