Campaigners called for more work to raise awareness, amid concerns women are not reporting incidents because they do not know about the law.
Crown Prosecution Service(CPS) statistics show 16 men have been convicted of 48 upskirting offences since April 2019 in England and Wales, including four who were given prison sentences.
Data shows the vast majority of the offences (33) took place in supermarkets and shops, with nine on public transport, five in the street and one in a school.
The law was introduced after Gina Martin lobbied the government for two years when she was unable to prosecute a man who took a picture up her skirt at a music festival.
Those convicted in England and Wales face prison sentences of up to two years, although the crime can also be punished with a fine on summary conviction.
Siobhan Blake, the CPS lead for sexual offences, said: “It has now been a year since this degrading practice became a specific criminal offence but women continue to be violated as they go about their daily lives.
“This appears to be a particular problem in shops and on public transport, where predatory men are concealing devices to take pictures up women’s skirts.
“This is a serious crime and I am very pleased to see police and prosecutors making regular use of this legislation.”
The NSPCC described the law as a “really good step forward” in offering a route to justice for victims and broadening understanding of what sexual abuse is.
But the charity said there remained the need for greater education in schools about what amounts to abuse in an effort to stop teenagers sharing harmful images.