Photonics Dictionary: O

A method for characterizing a fiber wherein an optical pulse is transmitted through the fiber, and the resulting light scattered and reflected to the input is measured (by an optical time-domain...

A surveying device used to measure vertical displacement of target centers of scale lines from a horizontal plane generated by up to 360° of sweep around its precision vertical axis.

Sets of paired lines carefully designed to give the most accurate pointing possible for various lengths of sight.

Optical tweezers refer to a scientific instrument that uses the pressure of laser light to trap and manipulate microscopic objects, such as particles or biological cells, in three dimensions. This...

A material that can rotate the polarization of light that passes through it. An optically active material exhibits different refractive indices for left- and right-circular polarizations (circular...

One of a class of crystalline substances belonging to triclinic, monoclinic and orthorhombic systems that have two optic axes. Two polarizations are allowed for any given direction of propagation,...

A transparent crystalline substance that displays the same optical properties (i.e. refractive index) in all directions such that all light rays behave the same in all directions of propagation and...

A laser in which stimulated emission is triggered by the absorption by electrons of light from an auxiliary source such as a flash lamp, or another laser. See optical pumping.

A transparent crystalline substance in which the refractive index of the optic axis (extraordinary axis) is different from the other two crystal axes. Two polarization directions are allowed for any...

Optics is the branch of physics that studies the behavior and properties of light, including its interactions with matter and its manifestation as both particle and wave phenomena. It encompasses the...

The area of optics that deals with the interaction of light with a given material. The optical properties of material are generally described by the absorption, transmission, reflection, and...

Optoacoustic, or photoacoustic, refers to a phenomenon and related techniques that involve the generation of acoustic waves in a material induced by the absorption of light. The term "optoacoustic"...

Pertaining to a device that responds to optical power, emits or modifies optical radiation, or utilizes optical radiation for its internal operation. Any device that functions as an...

Optoelectronics is a branch of electronics that focuses on the study and application of devices and systems that use light and its interactions with different materials. The term "optoelectronics" is...

Optofluidics is an interdisciplinary field that combines principles from optics and fluidics to create devices and systems that integrate the manipulation of light and fluids. This field focuses on...

A discipline that combines optics and genetics to enable the use of light to stimulate and control cells in living tissue, typically neurons, which have been genetically modified to respond to light....

An optical coupling device that uses light to bridge the gap between incompatible wire communications systems. It contains an input amplifier, a light-emitting diode, a photodiode and an output...

Optomechanical refers to the integration of optical and mechanical systems or components. In optomechanical systems, optics (related to the manipulation of light) and mechanics (related to the...

An instrument designed to measure the refractive power and range of accommodation of the eye. See ophthalmic instruments.

In the context of imaging, particularly digital imaging and printing, "orange peel" refers to a texture or visual distortion that resembles the surface of an orange peel. This texture can result from...

The ray that has an isotropic speed and maintains a uniform polarization in all propagation directions when traveling in a doubly refracting (birefringent) crystal. It obeys Snell's law upon...

Any organic substance, that when dissolved in appropriate liquid based solvents will absorb and emit electromagnetic radiation in the near ultraviolet, visible and near infrared spectral regions....

A laser having a lasing material that is a fluorescing organic dye. Depending on the dye used, it can produce emission in any part of the visible spectrum into the near-infrared and ultraviolet, and...

An organic light-emitting diode (OLED) is a type of light-emitting diode (LED) technology that utilizes organic compounds to produce light. OLEDs are commonly used in display technologies, such as...

A crystal having the axes of its grains aligned so that they have directional magnetic characteristics.

A lenticular screen having the lenticules tipped about 20° to compensate for off-normal projection.

A television camera tube in which a low-velocity electron beam scans a photoactive mosaic that has been created by an optical image. Once scanned by the electron beam, the electrical storage capacity...

A camera designed with a telecentric optical system and a narrow field of view; the telecentric optical system (placement of the system's stop at its focal point) ensures that the principal image...

Corrected for distortion.

An instrument used to record rapidly varying currents or voltages. An oscillograph may consist of a cathode-ray tube oscilloscope with a camera attachment, or a mirror galvanometer with a lamp and...

A system in which a supplied signal causes the deflection of the electron beam in a cathode-ray tube, thus forming a visible trace on the phosphor screen of the tube and providing for examination of...

Opsins are a group of light-sensitive proteins found primarily in the retinas of vertebrate and invertebrate eyes, as well as in other light-sensitive tissues. These proteins play a crucial role in...

The system of color classification and description produced by Wilhelm Ostwald.

An otoscope is a medical device used by healthcare professionals, particularly ear, nose, and throat (ENT) specialists, primary care physicians, and pediatricians, to examine the ear canal and...

The approximate dimension of the refractive-index correlation length in a given medium.

The emission of gas or de-aeration due to thermal variations and often occurring in a vacuum. In a cleanroom, contamination from the spontaneous emission of absorbed particles.

The direct computation of the Fourier transform of the space variant system output of an optical processor with a single spherical lens. The one-dimensional output spectrum appears along a 45°...

A layer of material applied to a coated surface to protect it from physical or chemical action.