Photonics Dictionary: O

A common technique in microscopy, oblique illumination is one in which the object is illuminated by a light source that is at an oblique angle (on the side) to the optical axis. This technique is...

Off-axis paraboloid and ellipsoid mirrors are specialized optical components used in various optical systems, particularly in applications requiring precise focusing, collimation, or imaging of...

Oleophobic is a term used to describe substances or materials that repel or resist oils. The word oleophobic comes from the Greek words "oleo," meaning oil, and "phobos," meaning fear. Oleophobic...

A term describing a substance that is impervious to light; the characteristic of a substance that has no luminous transmittance.

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;...

Ophthalmology is a branch of medicine that focuses on the anatomy, physiology, and diseases of the eyes and visual system. Ophthalmologists are medical doctors who specialize in the diagnosis,...

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,...

The use of retroreflective projection technology (RPT) to project a background image onto a masked object, such as a vehicle or overcoat, thereby making the masked object appear invisible....

Optical cements and adhesives are specialized materials used in the assembly and bonding of optical components in optical systems. These materials are designed to provide secure and durable bonds...

Transparent glassy and or crystalline structured materials engineered from inorganic, non-metallic materials via various methods that include heat or specific chemical reactions. Optical ceramics...

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)...

Optical character recognition (OCR) is a technology that is used to convert printed or handwritten text into machine-readable text. OCR software and systems are designed to recognize and extract...

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...

The storage of information via optical means, primarily employing a low-power laser to inscribe data on a photosensitive surface as pits or phase differences and to read such data via reflected light...

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...

Mathematically defined as the product of etendue (or throughput) and the square of the refractive index, the optical extent is the quantitative value that describes the geometrical limit to how much...

Optical fiber optic switches are devices used in optical fiber communication systems to selectively route optical signals from one input fiber to one or more output fibers. They play a crucial role...

Optical fiber is a thin, flexible, transparent strand or filament made of glass or plastic used for transmitting light signals over long distances with minimal loss of signal quality. It serves as a...

The amount by which an optical surface deviates from its ideal design value, expressed in wavelengths of light. Optical manufacturers use this value to determine two common characteristics of an...

An optical filter is a device that selectively transmits or blocks specific wavelengths, or colors, of light. Optical filters are used to control the spectral content of light in various...

The fluorographic method whereby the visible image (as opposed to the x-ray image) is photographed by mounting a camera in front of the fluorescent screen.

The optical Fourier transform is a mathematical operation applied to optical signals that involves transforming a spatial domain representation of an image into its corresponding frequency domain...

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...

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....

Optical materials refer to substances or compounds specifically chosen for their optical properties and used in the fabrication of optical components and systems. These materials are characterized by...

Laser-powered telephone device for analog communications that employs a vibrating plastic membrane as a transmitter to modulate laser light piped via optical fibers from a central exchange, omitting...

Optical noise refers to undesirable fluctuations or disturbances in an optical signal that can affect the quality or integrity of the transmitted information. This type of noise is particularly...

A laser-pumped crystal with nonlinear optical properties inside of an optical resonator in which the output generates coherent light whose output can be tuned continuously over a variety of infrared...

The relative path difference (or phase shift) traveled between two rays that pass through different mediums from the same object point. For a perfect optical system, the optical path, or distance,...

Optical phase distortion refers to a phenomenon where the phase of an optical wavefront is altered as it propagates through a medium. This distortion can result from variations in the refractive...

Also known as the Wiener spectrum or the noise power spectrum, the optical power spectrum is a fundamental quantity in film-screen image quality evaluation. It is a means of describing image content...

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...

In an optical fiber or waveguide communications system, an optoelectronic device or module that receives an optical signal, converts this optical signal to an electrical signal which is then...

1.) Generally, the electromagnetic spectrum within the wavelength region extending from the vacuum ultraviolet at 40 nm to the far-infrared at 1 mm. 2.) The wavelength or color distribution...

Optical strain sensors are devices that utilize optical principles to measure the deformation or strain experienced by a material under mechanical stress. These sensors convert changes in strain into...

Optical switching refers to the process of controlling the routing or transmission of optical signals within a network using various techniques to selectively switch or redirect optical paths. This...

An optical table, also known as an optical bench or an optical breadboard, is a specialized platform used in optics laboratories for mounting and aligning optical components. These tables provide a...

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...

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,...

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...