New York • 3M Co., the conglomerate whose products range from Post-Its to respirators, computer arms and films for LCD TV screens, is trying to expand into the security market by buying Cogent Inc. for $943 million.

Cogent develops automated systems that read finger and palm prints, and it makes iris and face recognition systems used by government, law enforcement and border patrol agencies.

Cogent's board of directors already has agreed to the deal and is recommending that shareholders accept it. 3M said Monday it will pay $10.50 per share for Cogent, or nearly 18 percent above Cogent's closing price on Friday.

Shares of Cogent, which is based in Pasadena, Calif., rose $2.18 Monday, or 24 percent, to close at $11.09.

3M already operates a division for identification and authentication systems. Ming Hsieh, Cogent's founder and CEO, said the acquisition would help 3M compete in border control and law enforcement markets.

Nicholas Heymann, an analyst with Sterne Agee, said Cogent would complement 3M's existing business of making border-management products such as passports, visas and document readers and laminates.

As smart phones begin to replace credit cards as methods of payment, Heymann said Cogent should help put 3M supply biometric security authorization products — that is, systems that use characteristics such as palm prints or the eyes to identify people.

3M's tender offer for Cogent is expected to last 10 days. The acquisition is expected to close by year's end. Once completed, the deal should result in a charge of 9 cents to 10 cents per share during the next 12 months.