solar retinopathy
pho·to·ret·i·nop·a·thy
(fō'tō-ret'i-nop'ă-thē),See also: solar maculopathy.
solar retinopathy
spectrum
absorption spectrum The curve representing the relative absorption of a pigment or chemical substance as a function of the wavelength of light. Example: the absorption spectrum of rhodopsin. Syn. absorbance spectrum.
action spectrum A graphical representation of the relative energy necessary to produce a constant biological effect. Example: frequency of action potentials in a ganglion cell as a function of wavelength.
continuous spectrum A spectrum in which, over a considerable range, all wavelengths exist without any abrupt variation in intensity. Example: the spectrum of hot solids. See filament lamp.
electromagnetic spectrum The total range of all electromagnetic waves. It extends from the longest radio waves of some thousands of metres in wavelength through radar, microwave, infrared rays, visible rays (between wavelengths 780nm and 380nm) to ultraviolet rays, X-rays, gamma rays and cosmic rays with wavelengths as short as 8 ✕ 10−12mm. All these electromagnetic waves differ only in frequency (and wavelength) but have the same speed as light in a vacuum.
equal energy spectrum Spectrum in which all wavelengths have about the same amount of energy. See achromatic; white light.
fortification spectrum See scintillating scotoma.
invisible spectrum The portions of the entire electromagnetic spectrum that are made up of radiations other than those of the visible spectrum.
line spectrum Spectrum consisting of a series of discrete monochromatic lines (or narrow bands of monochromatic light) with large intensity differences and separated by intervals without radiations. Example: the spectrum emitted by an electric discharge through a gas or vapour under low pressure.
spectrum locus The representation of the spectral colour stimuli on a chromaticity diagram.
solar spectrum The spectrum formed by sunlight. It is crossed at intervals by Fraunhofer's lines.
visible spectrum The portion of the electromagnetic spectrum that can be perceived by the visual system. It is composed of radiations of wavelengths in the range between 380nm and 780nm in younger eyes. This range decreases with age especially due to lens absorption of short wavelengths becoming closer to 420nm than 380nm. See light.
| Table S4 Approximate values of the velocity, frequency and wavelength of electromagnetic radiations in a vacuum (the values represent a point within a range of radiations) | ||||||||
| wavelength | ||||||||
| radiation | velocity (m/s) | frequency (Hz) | (m) | (nm) | ||||
| AM radio | 3 ✕ 108 | 1 ✕ 106 | 3 ✕ 102 | 3 ✕ 1011 | ||||
| television | 3 ✕ 108 | 1 ✕ 108 | 3 | 3 ✕ 109 | ||||
| radar | 3 ✕ 108 | 1 ✕ 109 | 3 ✕ 10−1 | 3 ✕ 108 | ||||
| microwave | 3 ✕ 108 | 1 ✕ 1010 | 3 ✕ 10−2 | 3 ✕ 107 | ||||
| thermal infrared | 3 ✕ 108 | 1 ✕ 1013 | 3 ✕ 10−5 | 3 ✕ 104 | ||||
| near infrared | 3 ✕ 108 | 1 ✕ 1014 | 3 ✕ 10−6 | 3000 | ||||
| light | ||||||||
| red | 3 ✕ 108 | 3.94 ✕ 1014 | 7.6 ✕ 10−7 | 760 | ||||
| yellow | 3 ✕ 108 | 5.45 ✕ 1014 | 5.5 ✕ 10−7 | 550 | ||||
| violet | 3 ✕ 108 | 7.50 ✕ 1014 | 4.0 ✕ 10−7 | 400 | ||||
| ultraviolet | 3 ✕ 108 | 1 ✕ 1016 | 3 ✕ 10−8 | 30 | ||||
| X-rays | 3 ✕ 108 | 1 ✕ 1018 | 3 ✕ 10−10 | 0.3 | ||||
| gamma rays | 3 ✕ 108 | 1 ✕ 1021 | 3 ✕ 10−13 | 0.0003 | ||||