Photonics Dictionary: O

An electro-optical infrared tracker consisting of a beamsplitter, an illuminating source, an image dissector tube and an electronics unit, that automatically acquires and tracks particular eye...

An instrument for measuring opacity.

See eye test apparatus; ophthalmic instruments.

An instrument used to measure backscatter as well as optical return loss and reflectance within an optical fiber system by measuring the reflected light when a continuous wave is transmitted through...

A small low-power microscope or magnifier with a scale that is used to measure the exit pupil diameter and eye relief on visual instruments. Optical dynameters are often used to measure the...

An instrument that measures several optical parameters, such as optical power and wavelength, with a single measurement input.

An instrument for determining the temperature of a hot object by examining the color spectrum of the visible light it gives off and comparing it to the known temperature and wavelength spectrum of...

An optical time-domain reflectometer (OTDR) is a specialized instrument used in optical fiber communications to characterize and analyze the optical fibers' characteristics, including attenuation,...

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

A device that uses a photoelectric cell to determine the level of oxygenation in the blood.

A family of specialized instruments used by ophthalmologists and optometrists to study a patient's eyes and prescribe spectacles. It includes the ophthalmoscope to observe and photograph the retina;...

The capacity of a chiral substance such as a crystal or molecule to rotate the plane of polarized light that is transmitted through it. Any substance that cannot be superimposed onto it's mirror...

Optical artifacts refer to undesired or unintended effects that can occur in optical systems, such as microscopes, cameras, telescopes, and other optical instruments. These artifacts can distort or...

An optical assembly refers to a collection of optical components that are carefully arranged and aligned to perform a specific function within an optical system. These components may include lenses,...

A device for measuring linear dimensions. The optical caliper generally consists of two circularly mounted mirrors whose angular positions are monitored by an autocollimator, and that are capable of...

An optical channel monitor (OCM) is a device used in optical communication systems to monitor and analyze the performance of individual channels within a wavelength-division multiplexing (WDM)...

An optical clock is a highly precise and advanced timekeeping device that relies on the oscillations of electromagnetic radiation in the optical or ultraviolet part of the electromagnetic spectrum....

Optical coherence tomography (OCT) is an imaging technique used in medical diagnostics and biomedical research to obtain high-resolution, cross-sectional images of biological tissues. An OCT imaging...

Optical coherence tomography (OCT) is a non-invasive imaging technique used in medical and scientific fields to capture high-resolution, cross-sectional images of biological tissues. It provides...

Optical design and engineering services involve the development, customization, and optimization of optical systems and components to meet specific performance requirements and application needs....

Optical design software refers to specialized computer programs used by optical engineers, physicists, and designers to simulate, model, analyze, and optimize the performance of optical systems and...

An optical gate typically refers to a device or system that controls the transmission of light, allowing it to pass through or be blocked in a manner analogous to an electronic gate controlling the...

Optical glass refers to a type of glass specifically engineered and manufactured for use in optical components and systems, such as lenses, prisms, mirrors, and filters. Optical glass is...

A device for measuring diffraction grating efficiency at any angle of incidence, consisting of a reflectometer wherein the detector rotates around the grating at a specific distance and is attached...

Optical manufacturing tools and machinery encompass a wide range of equipment, instruments, and systems used in the fabrication, shaping, finishing, and testing of optical components and systems....

Also known as a white-light interferometer. Measures surface texture and shape from nanometer-scale roughness to millimeter-scale step heights. A standard arrangement includes an illumination source,...

A measure of image quality produced by an optical system. May be specified in terms of cycles per millimeter, referencing a repeating bar pattern; or angular resolution, referencing the angle...

An optical testing instrument is a device or system used to evaluate and measure the performance, quality, and characteristics of optical components, systems, and devices. These instruments play a...

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...

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...

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...

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...

The condition of the numerical aperture or beam diameter of the laser, LED, or other optical source being larger than the optical fiber core or other driven source. Also called overfilled launch...