By: Victoria Macdonald - Channel 4 News

The Swiss chemist Albert Hofmann, who described his psychedelic discovery as his 'problem child', has died aged 102.

It is a drug that has sparked debate like no other. LSD (lysergic acid diethylamide) opened the doors of perception for some, influencing music, art and psychology. Others, the so called "acid casualties", were left with irrevocable psychological damage. It was announced today that Albert Hofmann, the Swiss chemist who discovered the substance by accident , died yesterday aged 102.

He had hoped his drug would prove to be a "medicine for the soul" - but after its widespread use as a recreational drug he ended up calling it his "problem child". This report from our social affairs correspondent Victoria Macdonald contains strobe lighting.

He had hoped his drug would prove to be a "medicine for the soul" - but after its widespread use as a recreational drug he ended up calling it his "problem child". This report from our social affairs correspondent Victoria Macdonald contains strobe lighting.

Professor Albert Hofmann was the man who spawned a generation which turned on, tuned in and dropped out - whose discovery of lysergic acid diethylamide enhanced the summer of love, psychedelia and the counterculture.

Prof Hofmann was known as the father of LSD but it was a drug that he also described as his problem child. He once said, I produced the substance as a medicine, it's not my fault people abused it.

But use it and abuse it they did - in the 50s and 60s - embraced and promoted by the Harvard psychiatrist Professor Timothy Leary.

On Prof Hofmann's 100th birthday scientists gathered in Basel to celebrate his discovery. He took the drug a number of times but his first trip was a mistake - he absorbed it through his finger.

His second was the famous bicycle ride home in 1943. He described feeling terror being possessed by a demon and then being suffused with feelings of good fortune and gratitude, of every sound becoming colour and pattersns.

He wanted LSD to be used for psychiatric treatments like schizophrenia but the drug was banned.

LSD is derived from ergot, a grain fungus, and produces changes in perception and emotions. Despite its demonisation, there are no reports of anyone overdosing on the drug, though people are said to have died after falling out of windows, thinking they could fly. Heavy users have suffered permanent psychological damage.

Prof Hoffman worked for nearly four decades for the Swiss pharmaceutical company Sandoz until he retired in 1971. He died yesterday from a heart attack at the age of 102.