After a two-day surge in its stock price and volume, the Ann Arbor-based advanced electronics maker Advanced Photonix Inc. (NYSE Amex: API) Friday said it was company policy not to comment on "unusual market activity."

Some 2.2 million of the company's shares changed hands Thursday as the price jumped from $2.05 a share to close at $2.63, trading as high as $2.66.

The company's average trading volume over the past 30 days is 253,000 shares.

Over the past year, the company's shares have traded for as little as 41 cents.

The stock cooled a bit in trading Friday, falling to $2.50 a share on volume of 1.6 million shares.

A Web site called insidercow.com reported Friday that API CEO Richard Kurtz bought 1,000 shares of the stock on the open market on Thursday at prices between $2.08 and $2.10.

Advanced Photonix manufactures optoelectronic equipment, high-speed optical receivers and terahertz instrumentation. Products include patented silicon indium phosphide and gallium arsinide based photodetectors; high-speed optical receivers; and the T-Ray 4000 terahertz product platform.

More at www.advancedphotonix.com.