Fresnel Lensprice

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Scalable, additive process solutions to directly replicate advanced all-inorganic optics with high-quality, high-refractive index, high-transmission, and optically stable materials.  ​

Fresnel LensSheet

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Myrias platform technology can be implemented for a wide range of advanced optics with reduced size, weight, and part count as compared to traditional, curved, refractive optics in complex assemblies. ​

Although the mirror could effectively concentrate the light into an intense beam, it was necessary to rotate it to make it visible from any direction. This produced the now familiar revolving lighthouse beam, with the light appearing as a series of flashes. Mariners were not favourably disposed to these early flashing lights, contending that a fixed steady light was essential for a satisfactory bearing. However, the greatly increased intensity and the advantage of using a pattern of flashes to identify the light gradually overcame their objections. The first revolving-beam lighthouse was at Carlsten, near Marstrand, Sweden, in 1781.

With the advent of the Argand burner, a reliable and steady illuminant, it became possible to develop effective optical apparatuses for increasing the intensity of the light. In the first equipment of this type, known as the catoptric system, paraboloidal reflectors concentrated the light into a beam. In 1777 William Hutchinson of Liverpool, England, produced the first practical mirrors for lighthouses, consisting of a large number of small facets of silvered glass set in a plaster cast molded to a paraboloid form. More generally, shaped metal reflectors were used, silvered or highly polished. These were prone, however, to rapid deterioration from heat and corrosion; the glass facet reflector, although not as efficient, lasted longer. The best metallic reflectors available in 1820 were constructed of heavily silvered copper in the proportion of 6 ounces (170 grams) of silver to 16 ounces (454 grams) of copper (compared with the 0.5 ounce [14 grams] of silver to 16 ounces of copper commonly used for plated tableware of the period). With such heavy plating, cleaning cloths were kept for subsequent recovery of the silver. These mirrors could increase the intensity of an Argand burner, nominally about five candlepower, almost 400 times.

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Down-stream treatment options offer refractive index tuning from 1.9 to 2.3 and transparency in the visible and IR, providing benchmark field of view and numerical aperture. ​

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Myrias’  approach produces meta-optics and AR/VR waveguides rapidly, balancing cost, quality, design flexibility and materials stability.​

Prior to Fresnel’s invention the best mirror systems could produce a light of about 20,000 candlepower with an Argand burner. The Fresnel lens system increased this to 80,000 candlepower, roughly equivalent to a modern automobile headlamp. With the pressure oil burner, intensities of up to 1,000,000 candlepower could be achieved. For a light of this order, the burner mantle would measure 4 inches (100 mm) in diameter. The rotating lens system would have four large Fresnel glass lens panels, 12 feet high, mounted about four feet from the burner on a revolving lens carriage. The lens carriage would probably weigh five tons, about half of it being the weight of the glass alone. The rotating turntable would float in a circular cast-iron trough containing mercury. With this virtually frictionless support bearing, the entire assembly could be smoothly rotated by weight-driven clockwork. If the illuminant was acetylene gas, the lens rotation could be driven by gas pressure.

How does aFresnel lenswork

In 1821 Augustin Fresnel of France produced the first apparatus using the refracting properties of glass, now known as the dioptric system, or Fresnel lens. On a lens panel he surrounded a central bull’s-eye lens with a series of concentric glass prismatic rings. The panel collected light emitted by the lamp over a wide horizontal angle and also the light that would otherwise escape to the sky or to the sea, concentrating it into a narrow, horizontal pencil beam. With a number of lens panels rotating around the lamp, he was then able in 1824 to produce several revolving beams from a single light source, an improvement over the mirror that produces only a single beam. To collect more of the light wasted vertically, he added triangular prism sections above and below the main lens, which both refracted and reflected the light. By doing this he considerably steepened the angle of incidence at which rays shining up and down could be collected and made to emerge horizontally. Thus emerged the full Fresnel catadioptric system, the basis of all lighthouse lens systems today. To meet the requirement for a fixed all-around light, in 1836 English glassmaker William Cookson modified Fresnel’s principle by producing a cylindrical drum lens, which concentrated the light into an all-around fan beam. Although not as efficient as the rectangular panel, it provided a steady, all-around light. Small drum lenses, robust and compact, are widely used today for buoy and beacon work, eliminating the complication of a rotating mechanism; instead of revolving, their lights are flashed on and off by an electronic code unit.

Want to pilot test a product, but don’t want to invest in new tooling?​Myrias has access to facilities for wafer scale manufacturing.​

Installations of this type entered common use, although many were converted to electric lamps with electric motor drives. Modern lens equipment of the same type is much smaller, perhaps 30 inches (75 cm) high, mounted on ball bearings and driven by an electric motor. Lens panels can be molded in transparent plastic, which is lighter and cheaper. Drum lenses are also molded in plastic. In addition, with modern techniques, high-quality mirrors can be produced easily and cheaply.