The devices made by Gary Bolton, 47, at his Kent home and company offices, were nothing more than boxes with handles and antennae, the Old Bailey was told.
He ran Global Technology Ltd, a thriving company with a 3 million pound annual turnover. The company sold fake bomb detectors for up to 10,000 pounds each, claiming they could detect explosives, tobacco, ivory and even cash.
While sentencing Bolton, Judge Richard Hone described the equipment as "useless" and "dross".
"You were determined to bolster the illusion that the devices worked and you knew there was a spurious science to produce that end," the judge said.
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"They had a random detection rate. They were useless.
"Soldiers, police officers, customs officers and many others put their trust in a device which worked no better than random chance.
"The jury found you knew this but you carried on. Your profits were enormous," the judge said.
One purchaser X-rayed a device and found nothing inside the box, the court was told.
Jurors found Bolton guilty of a charge of making an article for use in the course of fraud and one of supplying an article for use in the course of fraud, between January 2007 and July last year.
The prosecution told the court Bolton had another fraudster's fake bomb detector in his house.
In a separate case, McCormick, 57, of Langport, Somerset, was jailed for 10 years in May for selling more than 7,000 fake detectors, the report said.