A unit of audio equipment maker Dolby Laboratories Inc. is suing Research In Motion Ltd. for patent infringement.

The suit alleges that RIM's Blackberry smartphones and PlayBook tablet devices use Dolby's patented digital audio compression technology without a licence.

Dolby's technology enables the playback of high-quality audio files using limited amounts of storage space.

The company is seeking financial damages and an injunction to halt the sale of RIM's products.

Dolby International filed its suits in the United States and Germany.

Research In Motion, based in Waterloo, Ont., had no comment.