Many people are familiar with facial recognition systems that unlock smartphones and game systems or allow access to our bank accounts online. But the current technology can require boxy projectors and lenses. Now, researchers report in Nano Letters a sleeker 3D surface imaging system with flatter, simplified optics. In proof-of-concept demonstrations, the new system recognized the face of Michelangelo’s David just as well as an existing smartphone system.
3D surface imaging is a common tool used in smartphone facial recognition, as well as in computer vision and autonomous driving. These systems typically consist of a dot projector that contains multiple components: a laser, lenses, a light guide and a diffractive optical element (DOE).
The DOE is a special kind of lens that breaks the laser beam into an array of about 32,000 infrared dots. So, when a person looks at a locked screen, the facial recognition system projects an array of dots onto most of their face, and the device’s camera reads the pattern created to confirm the identity. However, dot projector systems are relatively large for small devices such as smartphones. So, Yu-Heng Hong, Hao-Chung Kuo, Yao-Wei Huang and colleagues set out to develop a more compact facial recognition system that would be nearly flat and require less energy to operate.
To do this, the researchers replaced a traditional dot projector with a low-power laser and a flat gallium arsenide surface, significantly reducing the imaging device’s size and power consumption. They etched the top of this thin metallic surface with a nanopillar pattern, which creates a metasurface that scatters light as it passes through the material.
In this prototype, the low-powered laser light scatters into 45,700 infrared dots that are projected onto an object or face positioned in front of the light source. Like the dot projector system, the new system incorporates a camera to read the patterns that the infrared dots created.
In tests of the prototype, the system accurately identified a 3D replica of Michelangelo’s David by comparing the infrared dot patterns to online photos of the famous statue. Notably, it accomplished this using five to 10 times less power and on a platform with a surface area about 230 times smaller than a common dot-projector system. The researchers say their prototype demonstrates the usefulness of metasurfaces for effective small-scale low-power imaging solutions for facial recognition, robotics and extended reality.
More information: Wen-Cheng Hsu et al, Metasurface- and PCSEL-Based Structured Light for Monocular Depth Perception and Facial Recognition, Nano Letters (2024). DOI: 10.1021/acs.nanolett.3c05002
Journal information: Nano Letters
News
UCLA Scientists Uncover a “Hidden Weakness” in Some of the World’s Deadliest Cancers
A new study has uncovered an unexpected vulnerability in some of the deadliest cancers. Researchers at UCLA have identified a previously hidden weakness in some of the most aggressive cancers, pointing to a possible new way [...]
AI-designed universal coronavirus vaccine clears first human trial
Key Takeaways Super-Antigen Technology: Uses AI and machine learning to analyze viral genomes, creating a single vaccine that targets essential features across entire virus families, including coronaviruses and Ebola. Human Trials & Safety: Phase [...]
Researchers Discover a Hidden Vitamin D Problem That Persists Year-Round
A new study suggests that some groups may not experience the expected seasonal boost in vitamin D levels, even during the sunniest months of the year. Many people assume that spending more time outdoors [...]
Researchers Solve the Mystery Behind a Billion-Dollar Dental Implant Disease
Researchers have uncovered why a common and costly dental implant infection often resists antibiotics. Dental implants have helped tens of millions of people regain a full set of stable, functional teeth, something traditional dentures [...]
Nanoparticles inspired by lung fluid improve therapies targeting respiratory system
The CIC biomaGUNE Center for Cooperative Research in Biomaterials has developed pulmonary surfactant nanoparticles (the blend of lipids and proteins that line the alveoli and enables breathing), which are encapsulated [...]
Scientists Finally Uncover How a “Forever Chemical” Causes Birth Defects
PFDA, a PFAS “forever chemical,” can cause craniofacial birth defects by disrupting retinoic acid regulation during fetal development, revealing the first clear molecular mechanism behind the link. Researchers have long linked perfluoroalkyl and polyfluoroalkyl substances (PFAS), [...]
Scientists Have Discovered These Deadly Parasites Are Secretly Swapping DNA
Leishmania parasites appear to evolve through widespread genetic exchange, reshaping assumptions about how they adapt and spread. A parasite long thought to spread mostly by cloning itself may be far more genetically dynamic than [...]
Stanford’s Revolutionary New Microscope Reveals Living Cells in Stunning Detail
Stanford researchers have developed a microscope that can show how nanostructures interact inside living cells at the highest resolution achieved so far. The view into living cells just got better. Stanford researchers have merged [...]
What Bundibugyo Ebola vaccines and treatments are under development
By Mariam Sunny and Jennifer Rigby May 29 (Reuters) – Global health authorities are racing to identify medical options to help contain an Ebola outbreak in eastern Democratic Republic of Congo, linked to the [...]
Why More People in Their 30s Are Suddenly Getting Colon Cancer
A major Swiss study found that colorectal cancer is becoming increasingly common in adults under 50, even as rates decline in older age groups. Researchers in Switzerland have identified a concerning trend: while colorectal [...]
Researchers Compare MS Models to Human Tissue in Search for Better Therapies
Researchers identified key differences between two widely used multiple sclerosis models, showing how each can better study myelin damage, immune responses, and repair. The findings may improve efforts to develop treatments that restore lost [...]
Scientists Discover Genetic “Off Switch” That Supercharges CAR T Cells Against Cancer
A new study reveals a possible way to make CAR T-cell therapy more durable and effective by targeting a single gene-regulating protein. CAR T-cell therapy is widely seen as a breakthrough in personalized cancer [...]
New Vitamin B12-Based Therapy Could Change How Brain Cancer Is Treated
Researchers have identified a vitamin B12–based compound that appears capable of crossing the blood–brain barrier and selectively accumulating in glioblastoma tissue. For decades, one of the biggest problems in brain cancer treatment has had [...]
Simple Fiber Supplement Cuts Knee Arthritis Pain in Just 6 Weeks, Study Finds
A daily inulin supplement may help reduce knee osteoarthritis pain while revealing a possible link between gut health, muscle function, and pain sensitivity. For millions of people living with knee osteoarthritis, managing chronic pain [...]
This Common Vitamin May Help Stop Prediabetes From Turning Into Diabetes
Vitamin D may help prevent type 2 diabetes in people with specific genetic variations, offering a possible path toward personalized diabetes prevention. More than 40% of U.S. adults have prediabetes, a condition in which [...]
Ebola, hantavirus: Is the world prepared for the next pandemic?
Funding cuts to health research and a growing antivaccine movement are making it harder than ever to respond to viruses. The World Health Organization (WHO) has declared that an Ebola outbreak in Uganda and [...]















