Printed lasers that are so cheap that they could be disposed of after every use have been developed by a team of French and Hungarian researchers.
The technology is made possible with organic lasers, which amplify light with carbon-containing materials.
Organic lasers are not as common as inorganic lasers, like those found in laser pointers, DVD players, and optical mice, but they offer benefits such as high-yield photonic conversion, easy fabrication, low-cost and a wide range of wavelengths.
Organic lasers have failed to become commonplace because they degrade relatively quickly, but the new project could see them manufactured at such low cost they could be disposed of when they failed.
“The low-cost and easiness of laser chip fabrication are the most significant aspects of our results,” said Sébastien Sanaur, who worked on the project.
The team produced their ultra-low-cost organic laser using what is effectively an inkjet printer.
Inkjet printing is a relatively inexpensive manufacturing process that works by squirting small jets of fluid onto an underlying material.
Although consumers are more familiar with the kind of inkjet printers found in offices, the technology can be adapted to print electronic circuits, pharmaceutical drugs and even biological cells.
“By piezoelectric inkjet printing, you print ‘where you want, when you want,’ without wasting raw materials,” Sanaur said. The technique doesn’t require masks, can be done at room temperature and can print onto flexible materials.
The researchers tested a variety of possible inks, before settling on a commercial ink variety called EMD6415, which they mixed with dyes. The ink was printed in small square shapes onto a quartz slide.
The dyed ink acted as the core of the laser, called a gain medium. A gain medium amplifies light and produces the characteristically narrow, single-color laser beam.
A laser also requires mirrors to reflect light back and forth through the gain medium and an energy source, called a pump, to keep the light amplification going.
The disposable part of the new laser is the printed gain medium, which the researchers call the “lasing capsule.” They estimate it could be produced for only a few pence. Like the replaceable blades in a razor, the lasing capsule could be easily swapped out when it deteriorates.
The research team used two different types of dyes to produce laser emission ranging from yellow to deep red. Other dyes could cover the blue and green part of the spectrum, they predict.
With further development, the inexpensive inkjet-printed laser could send data over short plastic fibers and serve as a tool for analysing chemical or biological samples.
In March, South African journalists demonstrated a new type of laser that is able to output twisted beams for optical communication, laser machining and medicine technologies.