A laser pointer was aimed at a Calgary police helicopter, impairing the flight crew's vision, said police. (CBC)

A man was arrested early Tuesday morning after a laser pointer aimed at a police helicopter impaired the vision of the flight crew, Calgary police say.

The chopper was patrolling above the Franklin LRT station when it was hit by the green beam, said acting Insp. Keith Cain.

The crew immediately put on protective eyewear as the pilot took evasive action. The helicopter was targeted at least twice more during the search, police said.

Officers on the ground traced the laser beam back to a home in the 7800 block of Martha Haven Park N.E. in Martindale.

They arrested a man without incident, confiscating a "class 3B laser," which can damage an eye instantly, police said.

Jason John McConnell, 34, faces numerous charges including obstructing a peace officer, mischief and "projection of a bright light source at an aircraft," an offence under the Aeronautics Act.

"It's a big concern for us because it affects the ability of the helicopter to operate, and they don't know exactly what it is that's being pointed at them," said Cain.

"A lot of firearms could have a laser attached that they use for a sighting mechanism."