PARIS (Reuters) - French eyewear company Essilor, which is in the process of merging with Italian peer Luxottica, reported a dip in first-quarter sales on Friday as currency swings impacted its business.

Sales fell by 5.8 percent to 1.825 billion euros (1.58 billion pounds) from a year ago, hurt by the weakness of the dollar, Brazilian real and Chinese yuan currencies against the euro.

A rising euro can make products more expensive for overseas buyers, and also impact revenues earned in dollars when they are translated back into euros.

"After this sound start to the year, notably thanks to good performances in sunwear and e-commerce, we are confident that we will meet our full-year targets as the rollout of new products gathers pace over the next few months," said Essilor Chairman and Chief Executive Hubert Sagnières.

In March, European and U.S. competition regulators approved the 48 billion euros merger of Luxottica and Essilor.

The proposed tie-up between Luxottica, whose brands include Ray-Ban, and Essilor - which sells lenses under the Varilux brand - is aimed at taking advantage of an expected strong demand for prescription spectacles and sunglasses as populations age globally.

(Reporting by Sudip Kar-Gupta; Editing by Gopakumar Warrier)