Cardiff and Merthyr crown courts were two of the first in Wales and England to "go digital" as part of a Â£700m Ministry of Justice initiative.
Recorder of Cardiff, Judge Eleri Rees, said the move is saving court time.
It also means defence barristers are in a better position to advise their clients much sooner.
"We can all look at the screens and we can all talk about the same information," the judge told BBC Radio Wales.
"For example, in a trial if you wanted to refer the judge to an exhibit or a witness statement, we could all go immediately to that document instead of having to dig about and have something copied and handed up to the judge."
She added the move would also prevent victims of crime waiting weeks or months to find out if they have to go to court.
"My understanding is that even in these first few months, there has been a significant increase in the rate of guilty pleas coming in at an earlier stage."
Merthyr has been trialling the system since October 2015 and Cardiff started three months ago.
The judge's claim is backed up by the Crown Prosecution Service in Wales but it added more data is needed to confirm a trend.
And barrister Lucy Crowther, from Apex Chambers in Cardiff, has welcomed the new system.
"We're going to be able to get rid of the bad backs, the bad shoulders and the wheelie trolleys," she said.
"It's certainly far more efficient, we're certainly saving time and resources but I think we've still got quite a long way to go in terms of finishing the project off properly and implementing the teething problems we've had so far."
Courts that have swapped paper files for computers have seen a higher number of defendants entering early guilty pleas, a judge has claimed.