Mixing perversion with technology led to 30 days in prison for a Downingtown man yesterday in Chester County Court.

Judge Howard F. Riley Jr. imposed the sentence on Peter Allen, 46, for invading the privacy of a female shopper at an Exton store on June 2.

According to court records, the woman was in Michael's Arts & Crafts, where Allen repeatedly bumped into her, especially every time she "went to bend down or reach up." After she saw his cell phone, she suspected he was taking photos up her dress. She subsequently recorded his license-plate number and called police.

Less than an hour later, West Whiteland Township Police Detective Sandra L. Smith confronted Allen at his home, the criminal complaint said. Allen said he had been taking similar photos for about a month, and had photographed some women's legs at the Exton Barnes & Noble bookstore earlier that day, the complaint said.

Allen gave consent for the police to seize his laptop and camera phone, the complaint said. A forensics analysis revealed more than 50 images taken up women's skirts. The victim from Michael's was able to identify 10 images of herself, the complaint said.

Assistant District Attorney Michelle E. Frei said she requested jail time "given the circumstances of the case and the prior breaks" Allen has received.

Court records show that Allen was placed into a non-jail, rehabilitative program in Montgomery County in 1989 on charges of indecent exposure and open lewdness. In 1993, he received a year's probation in Bucks County Court for another open-lewdness case.

Contact staff writer Kathleen Brady Shea at 610-701-7625

or kbrady@phillynews.com.