A father with Asperger's syndrome is reeling from a judge's decision that the time he spent with his children was so poor it should be cut from 30 hours to four hours a fortnight.

The man, who was given the pseudonym "Mr Bratsch" by the Federal Circuit Court, previously spent every second weekend with his children, but their mother sought orders requesting sole parental responsibility and for his time to be reduced to six hours a fortnight.

She said his Asperger's syndrome meant he lacked empathy, misread the children's emotions and there was " no fun, joy or humour" in the relationship between them.

He believed that after-school activities were a waste of time that took them away from their homework, and read them books that were beyond their years, such as The Magic of Reality by biologist Richard Dawkins.

Many hours were spent trying to improve his 11-year-old daughter's maths skills, and his son, 9, felt hurt and rejected when he was left to his own devices.