Showing posts with label optical computing. Show all posts
Showing posts with label optical computing. Show all posts

Thursday, July 4, 2024

More Advances in Vision Tech


Nanostructured flat lens uses machine learning to 'see' more clearly, while using less power
Jan 2024, phys.org

Meta Imager - a lense that processes the image on the front-end, so it can be thinner and process more efficiently.

Vanderbilt University: Hanyu Zheng et al, Multichannel meta-imagers for accelerating machine vision, Nature Nanotechnology (2024). DOI: 10.1038/s41565-023-01557-2

Image credit: AI Art - What Does Sadness Look Like - 2022


Lab-grown retinas explain why people see colors dogs can't
Jan 2024, phys.org

Just Retinal Organoids - By tweaking the cellular properties of retinal organoids, the research team found that a molecule called retinoic acid (an offshoot of vitamin A) determines whether a cone will specialize in sensing red or green light. Only humans with normal vision and closely related primates develop the red sensor.

via Johns Hopkins University: Retinoic acid signaling regulates spatiotemporal specification of human green and red cones, PLoS Biology (2024). DOI: 10.1371/journal.pbio.3002464. 


A camera-based anti-facial recognition technique
Jan 2024, phys.org

Anti-Facial Recognition - obfuscating, synthesizing or changing images to increase the privacy of users

CamPro - whereas most techniques use post-processing to modify images after they were captured, this    technique works at the camera sensor level to produce images that can protect users' facial privacy without influencing other applications

Using a very simplified explanation - the team manipulated certain parameters at the signal processing layer of the camera, right after the sensor, to take away personal identifying information from the picture, but while leaving the other information like person detection and pose estimation. It works by adjusting the existing processing parameters, but without requiring redesigning the camera, and it's called "privacy-preserving by birth" (why not by design?).

What's more is that because the resulting image may not be "human readable", they put some code in there to make the face back into something that humans can see pretty good, yet doesn't have the data that a computer needs to see it. This is like how a stop sign with a picture of a banana on it can brick your self-driving car; it looks like a banana to you, or a mess of dots, or whatever, but to the computer it looks like something completely different and in fact makes the stop sign itself invisible.

via USSLAB at Zhejiang University: Wenjun Zhu et al, CamPro: Camera-based Anti-Facial Recognition, arXiv (2024). DOI: 10.48550/arxiv.2401.00151


Science fiction meets reality as researchers develop techniques to overcome obstructed views
Feb 2024, phys.org

Using an ordinary digital camera - "We're turning ordinary surfaces into mirrors to reveal regions, objects, and rooms that are outside our line of vision"

via University of South Florida: Robinson Czajkowski et al, Two-edge-resolved three-dimensional non-line-of-sight imaging with an ordinary camera, Nature Communications (2024). DOI: 10.1038/s41467-024-45397-7

AI Art - Vase of Golden Threads in Impossible Geometries by Escher and Lalique - 2022

Using 3D printing to make artificial eyeballs more quickly and accurately
Feb 2024, phys.org

Artificial eyeballs thought you knew

via Fraunhofer Institute for Computer Graphics Research at Technical University Darmstadt, NIHR Biomedical Research Centre for Ophthalmology at Moorfields Eye Hospital, UCL Institute of Ophthalmology: Johann Reinhard et al, Automatic data-driven design and 3D printing of custom ocular prostheses, Nature Communications (2024). DOI: 10.1038/s41467-024-45345-5


Pushing back the limits of optical imaging by processing trillions of frames per second
Mar 2024, phys.org

Femtophotography - trillions of frames per second, used for femtosecond laser ablation, shock-wave interaction with living cells, and optical chaos 

Optical Chaos - chaos generated by laser instabilities using different schemes in semiconductor and fiber lasers

via Énergie Matériaux Télécommunications Research Centre at INRS Institut National de la Recherche Scientifique, the Advanced Laser Light Source Laboratory, Institut Jean Lamour at the Université de Lorraine, and Huazhong University of Science and Technology: Jingdan Liu et al, Swept coded aperture real-time femtophotography, Nature Communications (2024). DOI: 10.1038/s41467-024-45820-z

 
AI-powered 'sonar' on smartglasses tracks gaze, facial expressions
Apr 2024, phys.org

Both use speakers and microphones mounted on an eyeglass frame to bounce inaudible soundwaves off the face and pick up reflected signals caused by face and eye movements. One device, GazeTrak, is the first eye-tracking system that relies on acoustic signals. The second, EyeEcho, is the first eyeglass-based system to continuously and accurately detect facial expressions and recreate them through an avatar in real-time.

via Cornell Smart Computer Interfaces for Future Interactions: Ke Li et al, GazeTrak: Exploring Acoustic-based Eye Tracking on a Glass Frame, arXiv (2024). DOI: 10.48550/arxiv.2402.14634


Advance in light-based computing shows capabilities for future smart cameras
Apr 2024, phys.org

A tiny array of transparent pixels could produce a fast, broadband, nonlinear response from low-power ambient light.

The thinness of the material makes it transparent, while it retains qualities that enable incoming photons to efficiently regulate electrical conductivity. The research team coupled the 2D semiconductor with a layer of liquid crystal and made it functional with an array of electrodes. The result is a smart filter comprising 10,000 pixels, each able to selectively and quickly darken in a nonlinear way when exposed to broadband ambient light.

"An inexpensive device measuring a couple of centimeters could make a low-powered camera work like a super-resolution camera"

via California NanoSystems Institute at UCLA: Dehui Zhang et al, Broadband nonlinear modulation of incoherent light using a transparent optoelectronic neuron array, Nature Communications (2024). DOI: 10.1038/s41467-024-46387-5

Wednesday, June 16, 2021

On Quantum Updates and the Photon Revolution


Quantum things are a big deal these days, but you know what's even more of a big deal? Photons. Just wait, you'll be getting upgraded from the Verizon Quantum plan to the Verizon Photon plan in like 2 years tops. Photons, i.e., light, is the electricity of the 21st century. 

^That image btw: "Stimulated Photon Emission" -- Illustration of a gold-covered probe tip injecting electrons into a carefully located imperfection in an atomically thin material. The energy from each electron causes the highly localized emission of a single photon, which may then be guided to a detector. Credit: Ignacio Gaubert, 2020.

Time-reversal of an unknown quantum state
Aug 2020, phys.org

Stochastic baths, who can say no?
Abstract - In the present work, the scientists propose using a thermodynamic reservoir at finite temperatures to form a high-entropy stochastic bath to thermalize a given quantum system and experimentally increase thermal disorder or entropy in the system. 
-A. V. Lebedev et al. Time-reversal of an unknown quantum state, Communications Physics (2020). DOI: 10.1038/s42005-020-00396-0
-Seth Lloyd et al. Quantum principal component analysis, Nature Physics (2014). DOI: 10.1038/nphys3029
-Gonzalo Manzano et al. Quantum Fluctuation Theorems for Arbitrary Environments: Adiabatic and Nonadiabatic Entropy Production, Physical Review X (2018). DOI: 10.1103/PhysRevX.8.031037
An electrical trigger fires single, identical photons
Oct 2020, phys.org

First time we're seeing "memory" used as an analogy for quantum coherence.

Also, "photons on demand"; wait for it.

via: Bruno Schuler et al, Electrically driven photon emission from individual atomic defects in monolayer WS2, Science Advances (2020). DOI: 10.1126/sciadv.abb5988

Quantum entanglement demonstrated aboard orbiting CubeSat
Jun 2020, phys.org

Quantum computing in outer space.
In a critical step toward creating a global quantum communications network, researchers have generated and detected quantum entanglement onboard a CubeSat nanosatellite weighing less than 2.6 kilograms and orbiting the Earth.
The coldest computers in the world
Aug 2020, BBC News

Also in outer space.

The world's first integrated quantum communication network
Jan 2021, phys.org

Yes they have; via the University of Science and Technology of China.

Using drones to create local quantum networks
Jan 2021, phys.org

This is what it will be like:
A team of researchers affiliated with several institutions in China has used drones to create a prototype of a small airborne quantum network. In their paper published in the journal Physical Review Letters, the researchers describe sending entangled particles from one drone to another and from a drone to the ground.
Robots learn faster with quantum technology
Mar 2021, phys.org
"We are just at the beginning of understanding the possibilities of quantum artificial intelligence" says Philip Walther, head of an international collaboration of experimental physicists, "and thus every new experimental result contributes to the development of this field, which is currently seen as one of the most fertile areas for quantum computing."
Fertile, indeed.

Photon Avalanche, Mikołaj Łukaszewicz at Polish Academy of Sciences, 2021

'Multiplying' light could be key to ultra-powerful optical computers
Feb 2021, phys.org

Using polaritons - which are half-light and half-matter

Heat-free optical switch would enable optical quantum computing chips
Mar 2021, phys.org

Molybdenum disulfide ushers in era of post-silicon photonics
Mar 2021, phys.org

Study suggests that silicon could be a photonics game-changer
Apr 2021, phys.org

In addition to being good for controlling electronic information, silicon is also good for controlling light, which will be integral to quantum computing. 

Discovered by mistake of course:
"Our finding was lucky because we weren't looking for it. We were trying to understand how a very small number of phosphorus atoms in a silicon crystal could be used for making a quantum computer and how to use light beams to control quantum information stored in the phosphorus atoms.

"We were astonished to find that the phosphorus atoms were re-emitting light beams that were almost as bright as the very intense laser we were shining on them. We shelved the data for a couple of years while we thought about proving where the beams were coming from. It's a great example of the way science proceeds by accident, and also how pan-European teams can still work together very effectively."

via University of Surrey: Nils Dessmann et al, Highly efficient THz four-wave mixing in doped silicon, Light: Science & Applications (2021). DOI: 10.1038/s41377-021-00509-6

Wafer-scale production of graphene-based photonic devices
Feb 2021, phys.org

It's here, graphene chips to the rescue.

via Graphene Flagship: Marco A. Giambra et al, Wafer-Scale Integration of Graphene-Based Photonic Devices, ACS Nano (2021). DOI: 10.1021/acsnano.0c09758