Entrepreneur Neil Abbott, 32, was told "all sentencing options are available" by magistrate Colin Bateman-Jones when he pleaded guilty to one charge of outraging public decency at Westminster Magistrates' Court on Friday.
The court heard Abbott, of Maxwell Road in Romford, East London, was on a drunken night out with friends last summer when he pushed through a queue and brazenly took a picture up a woman's skirt at Liverpool Street Station in London.
An eyewitness informed the victim, who alerted station staff, and they apprehended the intoxicated defendant.
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Prosecutor Jennifer Fadaka told the court the victim was "repulsed" by Abbott's actions and was left "extremely distressed, with a shaky voice".
She said: "It was clear he (Abbott) was drinking - he was unsteady on his feet.
"He said: 'Can I not just delete the picture? I've learnt my lesson'."
Ms Fadaka said police seized Abbott's phone after which several other upskirting images were discovered.
Defence counsel Claire McGrath said her client - who spent eight years working as a project manager in banking and finance before setting up his own business - found upskirting photos "attractive", but said there was no evidence he had taken them himself.
She said Abbott, who graduated from Loughborough University with a 2:1 degree in industrial design and technology, had shown genuine remorse for his actions.
She said: "Although we of course accept that it is a serious and unpleasant matter, it is a one-off, and there is no evidence that can be put forward that Mr Abbott has acted in this way before.
"I can honestly say that he has - in his own words to police - learned his lesson. This has had an extreme impact on him.
"It clearly was not targeted in any way. It was done when he was intoxicated, he was not acting like he usually would.
"It was done in the most obvious fashion. There was no sense of sophistication or trying to hide what he did. He pushed into the queue (to take the picture) and was seen straight away."
Ms McGrath said her client understood the impact the incident had on his victim, and said he was "very remorseful".
She said: "I can't tell you how many times he has telephoned me. He has expressed genuine remorse.
"I'm sure he will never be anywhere near the police station or the courts ever again."
Abbott, who was accompanied to court by his girlfriend of nearly three years, was released on bail ahead of sentencing.
He was not charged with a specific upskirting offence because the offence occurred in August 2018 - eight months before the new law came into being.