Aug 29 (Reuters) - Chipmaker Omnivision Technologies Inc forecast current-quarter adjusted profit largely below expectations as rising competition and a slowdown of U.S. smartphone sales led to an inventory pile-up, sending its shares down 10 percent in extended trading.
The company, which pioneered imaging sensors that use both sides of a chip to deliver better quality in a smaller-sized camera, forecast second-quarter adjusted earnings of 36 cents to 53 cents per share.
Analysts on average were expecting 49 cents, according to Thomson Reuters I/B/E/S.
The company said it expects revenue of $375 million to $410 million. Analysts were expecting $406.6 million.
LG Innotek Co Ltd, Cowell Electronics Co Ltd and Foxconn Technology Group, which supplies to Apple Inc, are Omnivision's largest customers.
Forecast for some of the company's products was hurt by intensifying competition, Chief Executive Shaw Hong said in a statement.
Gross margin fell to 17.4 percent in the first quarter from 19.1 percent a year earlier.
Net income rose to $23.1 million, or 42 cents per share, in the first quarter from $2.3 million, or 4 cents per share, a year earlier.
Excluding items, the company earned 55 cents per share.
Revenue rose 45 percent to $373.7 million.
Analysts had expected earnings of 43 cents per share on revenue of $376.6 million.