Probing the 'Glory Ring' Mystery
Ever notice bright, colored rings around a distant airplane? Researchers have described this phenomenon as a strong backscattering of light by droplets of water. While the theory was well-developed, it remained difficult to verify experimentally.
More than 50 years ago, H. Van de Hulst explained "glory" scattering in terms of waves traveling around the surface of each droplet. Each water particle radiated weak wavefronts in the direction of the observer.
A group of researchers from
Oklahoma State University in Stillwater fired electromagnetic pulses of 0.1 THz with a spectral peak at a wavelength of 1 mm at a 6.35-mm-diameter aluminum sphere. A short optical pulse from a laser directed at a dipole antenna generated the radiation. Another optoelectronic system, illuminated by a delayed laser pulse, allowed time-delayed reception of the scattered signal. By changing the time of delay, glory rays were separated from direct reflections. The scientists found the spectrum of the glory rings was consistent with theoretical models.
LATEST NEWS
- Exail Signs LLNL Contract, Partners with Eelume
Apr 26, 2024
- Menlo Moves U.S. HQ: Week in Brief: 4/26/2024
Apr 26, 2024
- Optofluidics Platform Keys Label-, Amplification-Free Rapid Diagnostic Tool
Apr 25, 2024
- DUV Lasers Made with Nonlinear Crystals Enhance Lithography Performance
Apr 25, 2024
- Teledyne e2v, Airy3D Collaborate on 3D Vision Solutions
Apr 24, 2024
- One-Step Hologram Generation Speeds 3D Display Creation
Apr 24, 2024
- Innovation Award Winners for Laser Technology Honored in Aachen
Apr 23, 2024
- Intech 2024: AI Arrives on the Shop Floor
Apr 22, 2024