Photonics Dictionary: E

Clear All Filters x point x E x
effective focal length -> focal length

The focal length of a lens is the distance between the lens's optical center (or principal point) and the image sensor or film when the lens is focused at infinity. In simple terms, it is the...

electro-optic modulator

An electro-optic modulator (EOM) is a device used to modulate the amplitude, phase, or polarization of light waves using an external electrical signal. Electro-optic modulation is a fundamental...

electronic band edge

The point at which short-wavelength transmission is cut off.

elliptical polarization -> polarization

Polarization refers to the orientation of oscillations in a transverse wave, such as light waves, radio waves, or other electromagnetic waves. In simpler terms, it describes the direction in which...

emission spectrum

An emission spectrum is a graphical representation or a characteristic pattern of the wavelengths or frequencies of light emitted by a source, such as an atom, molecule, or celestial object. It shows...

encoder -> optical encoder

A device designed to measure linear or rotary motion by detection of the movement of markings on a transparent medium past a fixed point of light. The encoder has a moving code plate, a glass disc...

entrance slit

The entrance slit, also known simply as the slit, is an essential component in optical instruments such as spectrometers and monochromators. It is a narrow opening or aperture through which light...

equidensities

1. A contour map of a photographic deposit consisting of lines and curves that join points of equal density. 2. The portrayal of a photograph's points of equal density in hues of yellow, cyan and...

equidensitometry

1. The use of an electronic microdensitometer to measure points of equal density on a photographic deposit. 2. A technique that simplifies a picture's density pattern by making a single isodensity...

equivalent air path

When a block of glass (prism, window, filter, etc.) is placed into a converging light bundle, it increases the physical distance to the point of focus. The equivalent air path for that block of glass...

equivalent focal length -> focal length

The focal length of a lens is the distance between the lens's optical center (or principal point) and the image sensor or film when the lens is focused at infinity. In simple terms, it is the...

Er:YAG laser

An Er:YAG laser is a type of solid-state laser that uses a crystal made of erbium-doped yttrium aluminum garnet (Er:Y3Al5O12) as the gain medium. The erbium (Er) ions are introduced into the crystal...

eutectic

The material that has the lowest possible constant melting point of any possible combination of the same components.

excitation purity

On the CIE chromaticity diagram, the distance from the achromatic point to the sample point, divided by the distance from the achromatic point through the sample point to the spectrum locus or purple...

extended source

A radiation source that, unlike the point source, can be resolved by the naked eye into a geometrical image.

extensometer

1. A strainmeter capable of measuring the change in the relationship between two reference points, provided that the points are separated by at least 20 to 30 m. 2. An instrument used to determine...

extreme ultraviolet

Extreme ultraviolet (EUV) refers to a specific range of electromagnetic radiation in the ultraviolet part of the spectrum. EUV radiation has wavelengths between 10 and 124 nanometers, which...

Photonics DictionaryE

We use cookies to improve user experience and analyze our website traffic as stated in our Privacy Policy. By using this website, you agree to the use of cookies unless you have disabled them.