The UB Office of Science, Technology Transfer and Economic Outreach (STOR) has submitted a provisional patent application detailing the production process to the U.S. Patent and Trademark Office.
To create the rainbow material, Liu and Xu sandwiched a photosensitive pre-polymer syrup between two glass slides. (A photosensitive substance is one whose physical properties change upon exposure to light.)
Next, they directed a laser beam through a curved lens placed above the pre-polymer solution. The lens divided and bent the laser beam into light of continuously varying wavelengths.
As this light hit the solution, monomers in the solution began joining into polymers, forming a continuous pattern of ridge-like polymer structures. Larger ridges rose where the light struck with more intensity.
The resulting structure is a thin filter that is rainbow-colored when viewed under white light. This is because the periodic polymer layers reflect a continuous spectrum of colors, from red on one end to indigo on the other.
The single-step fabrication method -- shining a laser light through a curved lens -- is affordable and relatively simple.
The filter the researchers created was about 25 millimeters long, but the technique they used is scalable: It's possible to create filters of different sizes by shining the laser through lenses of different sizes.
Gan said the next step for the researchers is to improve the quality of the rainbow filter. The team is also beginning to explore ideas for incorporating the technology into handheld devices.
|Contact: Charlotte Hsu|
University at Buffalo