The policeman shot and blinded by Raoul Moat has asked to take part in trials of a revolutionary machine which could restore his eyesight.

The experimental device would allow Pc David Rathband, 43, to "see" using 400 electrodes on his tongue.

He has already been offered a conditional place by researchers but must now raise the £16,000 required to take part.

The BrainPort technology, which was developed in the US, uses sunglasses equipped with an inch-long camera to send images to a hand held controller.

These are converted into low resolution black and white pictures which pulsate on a postage stamp size grid of electrodes, according to the light level in each area of the picture. The user then "feels" shape and movement on the tongue, which the brain learns to "see", interpreting the sensations as a visual image.

"I'd love to be able to see some shadows or a bit of light," the father-of-two told The Daily Mail. "Anything is better than nothing. It keeps me going as a bit of hope, but I'm careful not to put all my eggs in that basket.

"I've gone from a man who did things when I wanted to, to a man who has to depend on others to do things with me and for me."

On July 4 2010, Pc Rathband, from Cramlington, Northumberland, was shot in the face and shoulder from point blank range with a shotgun as he sat in his marked police car. The attack, which nearly ended his life, left him completely blind, while he still has more than 200 shotgun pellets lodged in his skull.

Pc Rathband now wears prosthetic eyes with bright-blue irises. His family is raising funds so he can take part in the BrainPort trial. His son, Ashley, 19, has set up a web campaign for donations. It has raised £1,823 so far.

To donate, go to http://www.davidrathband.co.uk/brainport.html