NEW YORK (AP) — Shares of Universal Display Corp. returned some of their gains Friday, the second day after the company reported fourth-quarter results that surpassed Wall Street estimates.

Universal Display posted its quarterly earnings Wednesday afternoon. The Ewing, N.J., company makes ingredients for displays that use organic light-emitting diodes, or OLEDs. Its key customer is Samsung Electronics Co.

In the fourth quarter, its revenue surged 51 percent to $28.1 million and topped analyst estimates as license fees nearly tripled to $15.4 million. The company's net income slipped to $5.4 million, or 12 cents per share, from the prior year, which was lifted by a tax benefit. Universal Display shares jumped 12.5 percent on Thursday.

Cowen & Co. analyst Robert Stone said Thursday that the OLED industry should grow about 60 percent in 2013, and Universal Display's outlook is conservative. He said sales of green emitters should start to pick up after Samsung launches its new Galaxy S IV phone. Stone kept an "Outperform" rating on Universal Display shares, although he lowered his expectations for the company's license payments and said costs will be higher than he expected.

The company gets most of its revenue from red emitters, but said it has high expectations for new green light emitters that should be more efficient.

Universal Display shares fell as much as 4.8 percent Friday morning, but recovered some of those losses and were down 4 cents to $31.34 in midday trading.

Universal Display's net income more than tripled in 2012, reaching $9.7 million, or 21 cents per share. Revenue rose 36 percent, to $83.2 million. The company said it believes sales will be between $110 million to $125 million in 2013. Analysts were expecting $122.5 million in revenue on average.