Harnessing the power of polarization
Not far from where Edwin Land — the inventor of the Polaroid camera — made his pioneering discoveries about polarized light, researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) are continuing to unlock the power of polarization.
Recently, a team of researchers led by Federico Capasso, the Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering, encoded multiple holographic images in a metasurface that can be unlocked separately with differently polarized light.
This advancement could improve holograms for anti-fraud protection and entertainment, as well as offer more control over the manipulation and measurement of polarization.
The research was published in Physical Review Letters.
“The novelty of this type of metasurface is that for the first time we have been able to embed vastly different images that don’t look at all like each other — like a cat and a dog — and access and project them independently using arbitrary states of polarization,” said Capasso, the senior author of the paper.
Polarization is the path along which light vibrates. Previous research from the Capasso lab used nanostructures sensitive to polarization to produce two different images encoded in the metasurface. However, those images were dependent on one another, meaning both were created but only one appeared in the field of vision.
The metasurface made of titanium dioxide, a widely available material, consists of an array of polarization-sensitive pillars — also called nanofins — that redirect the incident light. Unlike previous arrays, which were uniform in size, these nanofins vary in orientation, height and width, depending on the encoded images.
“Each nanofin has different, precisely controllable polarization properties,” said Noah Rubin, co-first author of the paper and graduate student in the Capasso Lab. “You use this library of elements to design the encoded image.”
Different polarizations read different elements.
“This metasurface can be encoded with any two images, and unlocked by any two polarizations, so long as they are perpendicular to each other,” said Rubin. “You can also embed different functionalities. It can be a lens for one polarization and if you go to a different polarization, it can be a hologram. So, this work is general statement about what can be done with metasurfaces and enables new optics for polarization.”
It allows you to compress a number of functionalities, which would normally spread over several components, and put them all in a single optical element.Tweet This
“This is another powerful example of metasurfaces,” said Capasso. “It allows you to compress a number of functionalities, which would normally spread over several components, and put them all in a single optical element.”
The Latest on: Holograms
via Google News
The Latest on: Holograms
- From holograms to Plexiglas walls: How Santa comes to the mall during a pandemicon November 29, 2020 at 2:09 am
Technology, ingenuity and a wee sprinkle of Christmas magic are allowing some malls to find ways for children to meet Santa Claus in a time of pandemic restrictions.
- Opinion: Will holograms of our loved ones help us grieve?on November 27, 2020 at 1:00 am
The average person’s persona, imprinted across digital platforms, is not buried as efficiently as our body.
- MICE event organisers turn to holograms to make industry COVID-19 safe | Videoon November 26, 2020 at 8:02 am
MICE event organisers are taking to holograms and 3D projections to help their industry take off safely amid the COVID-19 pandemic. Those taking part in such events can have a touch and feel of ...
- This Company Wants to Put a Human-Size Hologram Booth in Your Living Roomon November 25, 2020 at 6:00 am
The person on the other end—the one appearing as a hologram, that is—just needs to have a camera and be standing against a white background.
- Holograms and Post-Mortem Rightson November 24, 2020 at 11:10 am
If you follow pop culture, you might have noticed a new trend crop up—realistic-looking holograms of public figures. From Tupac Shakur at Coachella in 2012 to Michael Jackson at the Billboard ...
- HOPE XII: Make Your Own Hologramson November 23, 2020 at 4:00 pm
Prior to this weekend I had assumed making holograms to be beyond the average hacker’s reach, either in skill or treasure. I was proven wrong by a Club-Mate box full of electronics, and an ...
- Holograms Can’t Be Too Thinon November 23, 2020 at 4:00 pm
These displays aren’t holograms, they are just showing your eyes two different images like a 3D movie or a stereopticon. However, researchers from Australia and China are hoping to change that.
- The Pitch: Tilt Five brings tabletop games to life with augmented realityon November 23, 2020 at 8:47 am
Tilt Five offers a modern twist on video and board games, bringing holograms to the table with its augmented reality (AR) glasses, wands and board. The San Jose startup recently raised a $7.5 ...
- Hulu uses OOH holograms to bring 'Animaniacs' reboot to lifeon November 23, 2020 at 6:16 am
The three-dimensional characters appeared on vehicles parked at iconic locations such as Madison Square Garden, Times Square, Rockefeller Center, Santa Monica Pier, Sunset Strip and TCL Chinese ...
via Bing News