The design, by consultancy Webb deVlam, uses a Fresnel lens
to give the illusion of large embossed bubbles on the carton without affecting the dimensions of the pack.
The best performing concentrators were the 46 cm acrylic Fresnel lens
and thin-film parabolic reflector, having concentration ratios of 92 and 58, respectively.
Judging that the student was reacting well to his instructions and using the Fresnel lens
cut-and-wave-off lights as a backup, Lt.
The optical quality acrylic is the most widely applicable material for a concentrator Fresnel lens
, and is a good general-purpose material in the visible.
A new request-to-exit sensor from GE Security of Bradenton, Florida, combines Doppler Range Controlled Radar motion sensing and Fresnel lens
passive infrared (PIR) technologies.
One example is a two-page illustration that is an engineering record of the Block Island, Rhode Island southeast light from 1874, which provides descriptions of the simple Piano-Convex lens, the Buffon lens (circa 1748) and the now popular Fresnel lens
, which was developed by Frenchman Augustin-Jean Fresnel in 1821.
Some historians say the Fresnel lens
sparked a Union Army invasion of Tampa, but whether that's true or not, the lens was long gone when the soldiers arrived.
The goggles use a stereoscopic Fresnel lens
to break down normal sight and create blurred double-vision.
An excellent interpretive center has exhibits on local ecology as well as the lighthouse's history If you visit on weekends or during the summer, expect to wait up to an hour to climb the tower (110 stairs) for a glimpse of the Fresnel lens
, which was shipped in sections from New York, across Panama, and up the Pacific coast.
Whereas an ordinary lens must become thicker as it gets larger to accumulate a phase shift of many times 2[pi], a Fresnel lens
has a maximum thickness.
A museum on the island houses the original crystal and brass Fresnel lens
from the lighthouse.
The ship also has the Improved Fresnel Lens
Optical Landing System, IFLOLS.