Photonics Dictionary

A memory system composed of a stack of holographic plates, a mode-locked laser and a rapid detector array. Ultrashort laser pulses are used to extract information from the stack. In this way, storage...

Extraction of three-dimensional measurements from a stereo pair of photographs.

1. A stereoscope that has adjustable scales to allow the determination of distances and dimensions from stereoscopic photographs. 2. A device used to view pictures of the same section of the night...

A method of creating real three-dimensional models by using lasers driven by CAD software. In contrast to the normal practice of removing material, this process polymerizes a liquid to quickly...

Technique that provides two stereographic views of an object that are larger than the object itself, by means of mutually inclined lens axes or nominal separation of axes of parallel lenses.

The imaging of two photographs of a stereo pair, in complementary colors, for the preparation of contour maps.

An exaggerated depth appearance in stereo photographs caused by the lenses in the camera being farther apart than the eyes of the viewer.

The photographing of a scene from positions corresponding to the locations of both eyes. A viewing device is used to present one picture to each eye for fusion of the retinal images, giving a...

A motion-picture camera that can be advanced one frame at a time, either randomly or at set intervals. Used in animation and time-lapse photography.

A term referring to the pre-exposed hologram of the subject used in holographic interferometry.

A streak camera is a specialized instrument used to capture and analyze ultrafast phenomena, such as extremely short pulses of light or rapidly changing events. Unlike traditional cameras that...

The basic process of color photography whereby colors are subtracted from white light by means of filters, making all colors and intensities available.

An instrument consisting essentially of a photoelectric cell filtered to respond to a specified wavelength region, an amplifier of sufficient gain to provide power enough to control movement of a...

Supercontinuum refers to a broad spectrum of light that spans a wide range of wavelengths, typically from the visible to the near-infrared or even mid-infrared regions of the electromagnetic...

Swept-source optical coherence tomography is an imaging technique used in medical diagnostics, particularly in ophthalmology, to visualize and analyze the internal structures of biological tissues,...

A swept-source laser, also known as a wavelength-swept laser, is a type of laser that rapidly and continuously changes its emission wavelength over time. This continuous wavelength tuning is achieved...

A synchrotron is a type of particle accelerator that uses magnetic fields to steer charged particles, typically electrons or positrons, in a closed, circular or elliptical path. The name synchrotron...

An imaging technique in which an object moving through an interference field formed in space scatters light and is spatially recorded on a photographic film as a hologram. If the interference field...

1. A method of photographing distant objects with a lens of long focal length. 2. The reproduction of photographs over a distance by means of electricity.

An instrument used to measure the luminance (brightness) of a distant object. The object is viewed through a small telescope, and a mirror in the focal plane reflects an internal illuminated surface...

A method of taking radiographs at a distance from the object being photographed to decrease distortion.

The graph of the oscillating variations composing the wave of a video signal.

A contraction for "texture element." A base unit used in computer graphics that defines the surface of three-dimensional objects. Texels are obtained from texture memory and represent color to be...

A technique for detecting free radicals by their electronic spectra. The material to be studied is placed in a temperature-controlled furnace through which radiation is propagated onto a...

A term referring to various processes for forming visible images outside of a camera to be photographed on ordinary film. Unlike regular infrared photography, thermal photography is an indirect...

Also known as analog thermogram. The resultant photograph, illustrating, in tones ranging from black to white, the spatial relationship of the infrared radiation temperatures of the different details...

The instrument used to collect thermal radiation information on an object by scanning. It consists basically of a detector, a photoconductive element that converts incident radiation to an electrical...

Thermography is a technique that involves the use of an infrared imaging device, called a thermal camera or infrared camera, to detect and visualize the infrared radiation emitted by objects. This...

A type of holographic film widely used for industrial applications because it is inexpensive and erasable.

Multiple exposures of holograms, one for each position of a vibrating image, that are used for vibration analysis and that yield a record of the time-averaged irradiance distribution at the hologram...

Although low in sensitivity (approximately 10-7 m for helium-neon lasers), this holographic technique permits quantitative assessment of entire vibratory patterns of given structures in a single...

Time-lapse optical coherence tomography (OCT) refers to a medical imaging technique that captures a series of sequential OCT scans over time, allowing for the dynamic observation and monitoring of...

Technique that defocuses activity from surrounding planes by means of the relative motions at the point of interest.

A variation of tomography in which several photographs of a patient are taken at different angles, and back-projection of the resulting radiographs produces light distribution in a chosen...

A method of measuring total hemispherical emissivity of the plane surface of a solid that consists of thermally isolating a specimen of the material inside a vacuum, preheating it slightly above the...

A transmission electron microscope (TEM) is a powerful microscopy technique that uses a beam of electrons to create high-resolution images of extremely thin samples. In a TEM, electrons are...

An image affixed to a transparent photographic film or plate by photographic, printing or chemical methods. It may be viewed by transmitted light.

Imaging materials that generally consist of a polyester base, a transparent electrically conductive layer and an organic photoconductive top coating. When charged and exposed to light, an...

Photographic recording of rapid events at a rate exceeding 106 frames per second.

The process of microphotography that involves the reduction of the original at a ratio greater than 100 to 1. The process is usually accomplished by the use of a reduced-scale negative, which, in...

A highly accurate cathode-ray tube used to display information with the utmost efficient stability and resolution. The information is viewed as a series of points, particularly suited for...

Ultrasonic refers to sound waves with frequencies higher than the upper audible limit of human hearing, typically above 20,000 Hz. These waves are termed ultrasonic because they are beyond the range...