Soo Ee Hock captured 201 images of women's undergarments over a period of five months at various locations, including Ang Mo Kio Hub, Compass Point and Junction 8 shopping centres.
The 36-year-old sales manager would clip a black camera pen to the side of his laptop bag and place the bag under the skirts of women standing in front of him as they went up escalators from November 2008 and March 2009.
The married man would transfer the videos onto his company-issued laptop before copying selected clips onto a CD.
The Straits Times reported that his offences came to light in July last year, after an unknown woman at Junction 8 in Bishan approached a cleaning staff member to tell her that a "male Chinese pervert" was trying to record images of women's undergarments.
He was then tailed by two security officers and was arrested by the police. The pen, which has a USB port and contains a pinhole camera that can capture videos and sounds, and a disk were found on him.
Yesterday, Soo pleaded guilty to 12 charges of intruding on the privacy of women by video-recording upskirt images. He also admitted he would always target and aim the camera pen at women wearing mid- to short-length skirts.
He originally faced 201 such charges, but 189 were taken into consideration.
According Channel News Asia, Soo's lawyer Jeffrey Beh told the court his client had committed the offences when he was going through a stressful time at work and at home.
But Deputy Public Prosecutor Anamika Bagchi said that Soo had repeatedly taken videos of unsuspecting victims and the acts were pre-planned and not committed at the spur of the moment.
Soo will be sentenced on December 14.
District Judge Lee Poh Choo postponed sentencing to Dec 14.
The maximum penalty is a year's jail and a fine on each charge of insulting modesty.
