Dark adaptor goggles
Encyclopedia
Dark adaptor goggles are used in the field of meteorology
Meteorology
Meteorology is the interdisciplinary scientific study of the atmosphere. Studies in the field stretch back millennia, though significant progress in meteorology did not occur until the 18th century. The 19th century saw breakthroughs occur after observing networks developed across several countries...

 for either adapting the eyes to the dark prior to an observation at night or to aid with the identification of cloud
Cloud
A cloud is a visible mass of liquid droplets or frozen crystals made of water and/or various chemicals suspended in the atmosphere above the surface of a planetary body. They are also known as aerosols. Clouds in Earth's atmosphere are studied in the cloud physics branch of meteorology...

s during bright sunshine or glare from snow. The goggles
Goggles
Goggles or safety glasses are forms of protective eyewear that usually enclose or protect the area surrounding the eye in order to prevent particulates, water or chemicals from striking the eyes. They are used in chemistry laboratories and in woodworking. They are often used in snow sports as well,...

 are made with red-tinted plastic lenses. Although the goggles are designed to be worn inside some people find walking, especially up and down stairs, to be difficult.

For use at night the observer should put the goggles on about ten minutes prior to going outside. Once the observer is outside and away from major sources of light the goggles may be removed and the observer's vision should be adapted to the dark.

To help with the identification of clouds during the day the goggles should be put on just before the observer goes outside. This will ensure the eyes are not affected by the glare
Glare (vision)
Glare is difficulty seeing in the presence of bright light such as direct or reflected sunlight or artificial light such as car headlamps at night. Because of this, some cars include mirrors with automatic anti-glare functions....

 from the sun or snow.

At no time should the goggles be used to help assess the visibility
Visibility
In meteorology, visibility is a measure of the distance at which an object or light can be clearly discerned. It is reported within surface weather observations and METAR code either in meters or statute miles, depending upon the country. Visibility affects all forms of traffic: roads, sailing...

.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK