Dark adaptor goggles, also called red adaptation goggles, are used in the field of
meteorology
Meteorology is a branch of the atmospheric sciences (which include atmospheric chemistry and physics) with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did no ...
and
astronomy
Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, g ...
for
adapting the eyes
to the dark prior to an observation at night. They also aid with the identification of
cloud
In meteorology, a cloud is an aerosol consisting of a visible mass of miniature liquid droplets, frozen crystals, or other particles suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may ...
s during bright sunshine or glare from snow. The
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 ...
are made with red-tinted plastic lenses. Such goggles or glasses are often used by pilots and weather observers to preserve their natural
night vision.
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 from the sun or snow. 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. Although the goggles are designed to be worn indoors, some people find walking around inside, especially up and down stairs, to be difficult.
At no time should the goggles be used to help assess the
visibility
The visibility is the measure of the distance at which an object or light can be clearly discerned. In meteorology it depends on the transparency of the surrounding air and as such, it is unchanging no matter the ambient light level or time o ...
.
Concept
Dark adaptor goggles were invented by
Wilhelm Trendelenburg in 1916.
Red Goggles (ca. 1940s)
/ref>
The concept is based on the work by Antoine Béclère on dark adaptation of the eye, where it is noted that fluoroscopy
Fluoroscopy () is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope () allows a physician to see the internal structure and function ...
relies on the use of the retinal rods
Rod cells are photoreceptor cells in the retina of the eye that can function in lower light better than the other type of visual photoreceptor, cone cells. Rods are usually found concentrated at the outer edges of the retina and are used in p ...
of the eye.
Since retinal rods are insensitive to long wavelengths of light, such as red light, while retinal cones
Cone cells, or cones, are photoreceptor cells in the retinas of vertebrate eyes including the human eye. They respond differently to light of different wavelengths, and the combination of their responses is responsible for color vision. Cone ...
are not, the 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 ...
enabled the physician
A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...
s to adapt their eyes in preparation for the fluoroscopic procedure while still being able to perform other work. Prior to the invention of these goggles, physicians were required to sit in the darkened room where the procedure would be performed for extended periods to adapt their eyes to the low lighting conditions.
See also
* Purkinje effect
The Purkinje effect (; sometimes called the Purkinje shift, often incorrectly pronounced ) is the tendency for the peak luminance sensitivity of the eye to shift toward the blue end of the color spectrum at low illumination levels as part of da ...
References
* Environment CanadaAtmospheric Environment Services, Manual of Surface Weather Observations (MANOBS), 7th Edition, January 1977.
{{Eyewear
Meteorological instrumentation and equipment
Goggles