Photonics West: Monday

25 Jan 2005

French researchers build an inkjet printer that can cut paper as it prints, thanks to an infrared laser diode.

A desktop printer that uses a built-in laser to cut out images as it prints could soon be heading to the market, according to scientists from the CEA in France. Presenting the idea to a packed conference hall at Photonics West, Olivier Acher says the printer could make anything from business cards and address labels to tear-off slips and trimmed photos.

“With the boom in digital photography, people are now printing photos at home,” Acher told the audience. “This printer would allow them to get their photo to an exact size or even cut out an outline of a person or an object in the photo.”

Cut as you print

Carbon dioxide lasers are a well-established technology when it comes to cutting reams of paper. But according to Acher, there is no way to scale this technology down to a price and speed suitable for desktop applications.

The French team chose a near-infrared diode laser as it offered a cost-effective solution, but there was a catch. “Laser diodes are not good at cutting white paper,” explained Acher. “Conventional paper absorbs less than 5% of light in the 450 – 1400 nm range.” To overcome this problem, Acher’s team has developed an invisible ink that penetrates deep into the paper and absorbs the light from the diode.

tear off strips

Acher’s idea integrates the diode laser and an extra ink cartridge containing the invisible ink into a conventional inkjet printer. The document is printed normally, followed by the invisible ink where cuts are required.

Using a 1 W 840 nm diode, standard paper can be cut at speeds up to 75 cm/minute with a 30 µm spot. To create perforations instead of cuts, the laser speed is simply increased. Crucially, Acher says the laser only interacts with the invisible ink and leaves no trace of burning on the paper.

Having demonstrated the idea, Acher and co-workers now hope to commercialize it. “We are looking for a licensing partner in the printing industry,” he said. “We are also looking for a high power single emitter diode laser maker to help us assess different powers.”

Author
Jacqueline Hewett is technology editor on Optics.org and Opto & Laser Europe magazine.