And those developing the machine, called computer tomography laser mammography (CTLM), stress that it could remove much of the discomfort associated with breast screening.

The laser, a concentrated and closely targeted beam of light, is fired through the breast tissue, but does not cause any burning or bruising.

It works by reacting differently to healthy breast tissue and cancerous tumour tissue.

Breast cancer cells are more dense than healthy cells

The cancer tissue is more densely packed with cells, meaning that less of the laser light will pass through to be picked up by a sensor on the other side.

The machine spins around the breast and, by covering each spot from a variety of different angles, builds up a highly accurate three-dimensional image which should highlight any worrying areas.

While X-ray mammography requires the breast to be pushed hard against the machine to ensure the X-rays penetrate better, CTLM requires only that women lie face down and ease the breast through a hole in the table.

The company has proved to US safety officials that the laser moves too fast to cause any burning or bruising to the flesh, and their invention has now been set up for full trials to measure its effectiveness.

About 400 women will be screened using existing methods, and the new machine, and the success rate at spotting tumours compared.

The company believes that it will eventually become a back-up for conventional mammography.

The UK currently screens all women between the ages of 50 and 64, once every three years.