100,000 Dots-Per-Inch (DPI) image resolution is achieved using metal-laced nanostructures

Researchers from Institute of Materials Research and Engineering (IMRE) have developed an innovative method for creating sharp, full-spectrum colour images at 100,000 dots per inch (dpi), using metal-pattern nanostructures, without the need for inks. In comparison, current industrial printers such as inkjet and laser jet printers can only achieve up to 10,000 dpi while research grade methods are able to dispense dyes for only single colour images. This novel breakthrough using lithographic technique which can potentially revolutionise the way images are printed and be developed for use in high-resolution reflective colour displays as well as high density optical data storage.

 The inspiration for the research was derived from stained glass, which is traditionally made by mixing tiny fragments of metal into the glass. It was found that nanoparticles from these metal fragments scattered light passing through the glass to give stained glass its colours. Using a similar concept with the help of modern nanotechnology tools, the researchers precisely patterned metal nanostructures, and designed the surface to reflect the light to achieve the colour images.

The resolution of printed colour images very much depends on the size and spacing between individual nanodots. The closer the dots are together and because of their small size, the higher the resolution of the image. With the ability to accurately position these extremely small colour dots, the highest theoretical print colour resolution of 100,000 dpi could be achieved.

Instead of using different dyes for different colours, colour information is encoded into the size and position of tiny metal disks. These disks then interacted with light through the phenomenon of plasmon resonances. Nanostructure pattern, size and spacing are then correlated with the database of colour. These nanostructures were then positioned accordingly.