Precursors Inuit snow goggles function by reducing exposure to sunlight, not by reducing its intensity Antoine Lavoisier conducting an experiment related to combustion generated by amplified sun light. In prehistoric and historic time, Inuit peoples wore flattened walrus ivory "glasses" , looking through narrow slits to block harmful reflected rays of the Sun .Inuit hero 'Nanook' from the silent documentary film Nanook of the North (1922) wearing whale bone snow-goggles Retrieved December 5, 2014 In many different forms and with many different materials, the indigenous peoples of North America and northern Asia crafted highly efficient equipment to protect their eyes against the damaging effects of strong sunlight in snowy circumstances.Thompson, Clive, These Snow Goggles Demonstrate Thousands of Years of Indigenous Ingenuity, Smithsonian, January, 2020 The most widespread protection is against ultraviolet radiation, which can cause short-term and long-term ocular problems such as photokeratitis , snow blindness , cataracts, pterygium, and various forms of eye cancer. Medical experts advise the public on the importance of wearing sunglasses to protect the eyes from UV; for adequate protection, experts recommend sunglasses that reflect or filter out 99\% or more of UVA and UVB light, with wavelengths up to 400 nm. Sunglasses that meet this requirement are often labeled as "UV400". This is slightly more protection than the widely used standard of the European Union (see below), which requires that 95\% of the radiation up to only 380 nm must be reflected or filtered out.Siegfried Hünig, in consultation with Albert J. Augustin (Oct. 2007). Sehschaden im Alter vorbeugen und mildern. Informationen und Empfehlungen zur altersbedingten Makuladegeneration und zum grauen Star. [Preventing and Alleviating Vision Damage at Higher Age. Information and Recommendations for Age-Related Macular Degeneration]{{cbignore|bot=medic}}]. Manuscript hosted on the website of Klinikum Karlsruhe (retrieved 21 September 2009)Siegfried Hünig (2008). Optimierter Lichtschutz der Augen. Eine dringende Aufgabe und ihre Lösung. Teil 1: Beschaffenheit des Lichts, innere und äußere Abwehrmechanismen. [Optimized protection from light-inflicted eye damage. A pressing problem and a simple solution]{{dead link|date=November 2016 |bot=InternetArchiveBot |fix-attempted=yes }}. Zeitschrift für praktische Augenheilkunde, 29, pp. 111-116.Siegfried Hünig (2008). Optimierter Lichtschutz der Augen. Teil 2: Sehprozess als Risikofaktor, Lichtschutz durch Brillen [Optimized protection from light-inflicted eye damage. A pressing problem and a simple solution]{{dead link|date=November 2016 |bot=InternetArchiveBot |fix-attempted=yes }}. Zeitschrift für praktische Augenheilkunde, 29, pp. 197-205. Sunglasses are not sufficient to protect the eyes against permanent harm from looking directly at the Sun, even during a solar eclipse. Special eyewear known as solar viewers are required for direct viewing of the sun. This type of eyewear can filter out UV radiation harmful to the eyes.
Precursors Inuit snow goggles function by reducing exposure to sunlight, not by reducing its intensity Antoine Lavoisier conducting an experiment related to combustion generated by amplified sun light. In prehistoric and historic time, the Inuit wore flattened walrus or caribou ivory Snow goggles , looking through narrow slits to block harmful reflected rays of the sun .Inuit hero 'Nanook' from the silent documentary film Nanook of the North (1922) wearing whale bone snow-goggles Retrieved December 5, 2014 In many different forms and with many different materials, the indigenous peoples of North America and northern Asia crafted highly efficient equipment to protect their eyes against the damaging effects of strong sunlight in snowy circumstances.Thompson, Clive, These Snow Goggles Demonstrate Thousands of Years of Indigenous Ingenuity, Smithsonian, January, 2020 The most widespread protection is against ultraviolet radiation, which can cause short-term and long-term ocular problems such as photokeratitis (snow blindness) , cataracts, pterygium, and various forms of eye cancer. Medical experts advise the public on the importance of wearing sunglasses to protect the eyes from UV; for adequate protection, experts recommend sunglasses that reflect or filter out 99\% or more of UVA and UVB light, with wavelengths up to 400 nm. Sunglasses that meet this requirement are often labeled as "UV400". This is slightly more protection than the widely used standard of the European Union (see below), which requires that 95\% of the radiation up to only 380 nm must be reflected or filtered out.Siegfried Hünig, in consultation with Albert J. Augustin (Oct. 2007). Sehschaden im Alter vorbeugen und mildern. Informationen und Empfehlungen zur altersbedingten Makuladegeneration und zum grauen Star. [Preventing and Alleviating Vision Damage at Higher Age. Information and Recommendations for Age-Related Macular Degeneration]{{cbignore|bot=medic}}]. Manuscript hosted on the website of Klinikum Karlsruhe (retrieved 21 September 2009)Siegfried Hünig (2008). Optimierter Lichtschutz der Augen. Eine dringende Aufgabe und ihre Lösung. Teil 1: Beschaffenheit des Lichts, innere und äußere Abwehrmechanismen. [Optimized protection from light-inflicted eye damage. A pressing problem and a simple solution]{{dead link|date=November 2016 |bot=InternetArchiveBot |fix-attempted=yes }}. Zeitschrift für praktische Augenheilkunde, 29, pp. 111-116.Siegfried Hünig (2008). Optimierter Lichtschutz der Augen. Teil 2: Sehprozess als Risikofaktor, Lichtschutz durch Brillen [Optimized protection from light-inflicted eye damage. A pressing problem and a simple solution]{{dead link|date=November 2016 |bot=InternetArchiveBot |fix-attempted=yes }}. Zeitschrift für praktische Augenheilkunde, 29, pp. 197-205. Sunglasses are not sufficient to protect the eyes against permanent harm from looking directly at the Sun, even during a solar eclipse. Special eyewear known as solar viewers are required for direct viewing of the sun. This type of eyewear can filter out UV radiation harmful to the eyes.
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Inuit peoples
the Inuit
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ivory "glasses"
or caribou ivory Snow goggles
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Sun
sun
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, snow blindness
(snow blindness)