Fresnel lenses: High contrast and efficient focusing

October 5, 2012
Carbon nanotube Fresnel lens

The first Fresnel lens was installed in 1823 in the Cordouan lighthouse, where its beam was visible for 32 km. Since then, this lens design has been used in lighthouses, traffic lights, automobile headlights, magnifying glasses, cameras, and more. Compared to a conventional lens design of comparable aperture and focal length, a Fresnel lens requires less mass and volume, allowing it to be thinner and flatter, capturing more oblique light from a light source.

Reflections from the opaque zones in a Fresnel lens can degrade the focusing and lensing properties, however. Tim Wilkinson and colleagues Ranjith Rajasekharan, Haider Butt, Qing Dai and Gehan Amaratunga, at the Department of Engineering overcame this limitation by using the darkest man-made material ever—low-density, vertically aligned carbon nanotube arrays.

Tim and his colleagues created arrays of carbon nanotube Fresnel lenses, each 77 micrometers in diameter and with fifteen zones. These lenses have exceptional optical properties, with high contrast and efficient focusing.

Their findings are published in an article in the journal Advanced , Volume 24, Issue 23, dedicated to breakthrough discoveries and fundamental research in the field of light-matter interactions. It includes communications, full papers, and reviews.

The authors say these fabricated carbon nanotube Fresnel lenses offer new possibilities in designing highly flexible and efficient interconnection networks with massive parallelism. Potential applications include efficient focusing, deflecting and collimating tasks in optical sensor systems, , optical data transfer, , and even integration into 2D source arrays for neural network architectures.

Explore further: World' First Transparent Ceramic Lens

More information: onlinelibrary.wiley.com/doi/10.1002/adma.201200296/abstract

The news above was originally posted by Dave Flanagan on www.advopticalmat.de/bright-idea-carbon-nanotube-fresnel-lenses

Related Stories

World' First Transparent Ceramic Lens

August 2, 2004

CASIO, Inc., in conjunction with its parent company, CASIO COMPUTER CO., LTD., Tokyo, Japan today announced that using its proprietary optical technology, CASIO COMPUTER CO., LTD., has developed the world’s first lens using ...

Liquid lens creates tiny flexible laser on a chip

May 11, 2009

(PhysOrg.com) -- Like tiny Jedi knights, tunable fluidic micro lenses can focus and direct light at will to count cells, evaluate molecules or create on-chip optical tweezers, according to a team of Penn State engineers. ...

Next generation lens promises more control

December 20, 2009

(PhysOrg.com) -- Duke University engineers have created a new generation of lens that could greatly improve the capabilities of telecommunications or radar systems to provide a wide field of view and greater detail.

Nanowire lens can reconfigure its imaging properties

October 11, 2011

(PhysOrg.com) -- By taking advantage of the unique optical properties of nanoscale materials, researchers have designed a lens made of nanowires that can reconfigure its imaging properties without any electronic or mechanical ...

Recommended for you

Magnetism at nanoscale

August 3, 2015

As the demand grows for ever smaller, smarter electronics, so does the demand for understanding materials' behavior at ever smaller scales. Physicists at the U.S. Department of Energy's Ames Laboratory are building a unique ...

Study calculates the speed of ice formation

August 3, 2015

Researchers at Princeton University have for the first time directly calculated the rate at which water crystallizes into ice in a realistic computer model of water molecules. The simulations, which were carried out on supercomputers, ...

Small tilt in magnets makes them viable memory chips

August 3, 2015

University of California, Berkeley, researchers have discovered a new way to switch the polarization of nanomagnets, paving the way for high-density storage to move from hard disks onto integrated circuits.

Scientists bring order, and color, to microparticles

August 3, 2015

A team of New York University scientists has developed a technique that prompts microparticles to form ordered structures in a variety of materials. The advance, which appears in the Journal of the American Chemical Society ...

2 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

PPihkala
not rated yet Oct 05, 2012
Are these small enough to have an individual lens for each pixel of digital camera? That could allow more efficient light capture, but might need the half pixel shift for every second row of pixels to pack the lenses more optimally.
Blakut
not rated yet Oct 06, 2012
^ With this technology could one make lensless cameras? Just a CMOS/CCD chip coated with these things? Hard to tell...

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.