(Reuters) - Japan's Canon Inc said it plans to buy security camera maker Axis AB for about 23.6 billion Swedish crowns ($2.83 billion) to expand into the surveillance products market amid weak sales of its cameras.

Canon said it was launching a tender offer to buy all of Axis shares for 340 crowns per share, a premium of nearly 50 percent to their closing price of 226.90 on Monday.

The Swedish company said its board of directors unanimously supported the offer.

Canon already sells surveillance cameras and sees it as a growing market, although it has not disclosed how much it earns from such products.

The deal comes after Canon late last month reported a slight increase in its fourth-quarter profit, as a weaker yen and rising sales of office equipment offset weakness in its camera division.

Axis reported a fourth-quarter operating profit of 199 million crowns, slightly below analysts' forecasts but up from 166 million a year ago. Around half of its sales come from the Americas, 40 percent from Europe, the Middle East and Africa and the rest in Asia.