Photonic-crystal-based spectrometer is small and simple

Feb. 1, 2010
Although photonic crystals (PCs) are inherently intricate, they can result in optical devices of great simplicity.

Although photonic crystals (PCs) are inherently intricate, they can result in optical devices of great simplicity. For example, a spectrometer created by engineers at Columbia University and the Cooper Union for the Advancement of Science and Art (both in New York, NY) consists merely of various PC patterns on a glass substrate, with a camera focused on the patterns. Different patterns correspond to different wavelengths; light introduced into the edge of the substrate gets coupled out at wavelength-dependent locations seen by the camera. The device works well for measuring broadband light sources used for illumination.

In the prototype, nine PC patterns with different lattice constants ranging from 300 to 420 nm were fabricated in a square grid in polymer film on glass; each PC pattern was 30 × 30 µm in size. The USB camera, which had a 4x objective, was first characterized with a programmable light source. The spectrometer was used to test a 5 mm white LED; the recovered spectrum matched well with measurements made with a standard commercial spectrometer. Increasing the number of different PC patterns will increase the accuracy and resolution of future versions of this device. Contact Nadia Pervez at [email protected].

More Laser Focus World Current Issue Articles
More Laser Focus World Archives Issue Articles

Sponsored Recommendations

Advancing Neuroscience Using High-Precision 3D Printing

March 7, 2025
Learn how Cold Spring Harbor Laboratory Used High-Precision 3D Printing to Advance Neuroscience Research using 3D Printed Optical Drives.

From Prototyping to Production: How High-Precision 3D Printing is Reinventing Electronics Manufacturing

March 7, 2025
Learn how micro 3D printing is enabling miniaturization. As products get smaller the challenge to manufacture small parts increases.

Sputtered Thin-film Coatings

Feb. 27, 2025
Optical thin-film coatings can be deposited by a variety of methods. Learn about 2 traditional methods and a deposition process called sputtering.

What are Notch Filters?

Feb. 27, 2025
Notch filters are ideal for applications that require nearly complete rejection of a laser line while passing as much non-laser light as possible.

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!