Photonics Dictionary

An optical instrument consisting of a well- corrected objective lens or mirror with a light source and or object/image (i.e. illuminated slit or retical) at its focal plane. Collimators are used to...

A color center, in the context of materials science and condensed matter physics, refers to a specific type of crystallographic defect in a crystalline structure that introduces color to the...

Equipment for testing an observer's color vision. Some tests require the identification or ordering of colored samples. The commercially available examples include: the Ishihara plates, on which...

A colorimeter is a device used to measure and quantify the color characteristics of an object or a light source. It provides objective and standardized color information, typically expressed in terms...

A lens aberration, resulting from different magnifications in the various lens zones, that occurs in that part of the image field that is some distance from the principal axis of the system....

1. An eyepiece or magnifier with a scale at its image plane. That scale is placed in contact with an object, permitting direct measurement of its size. 2. Also called traveling stage and traveling...

A computer-generated hologram (CGH) is a holographic image produced using computational methods and algorithms, rather than traditional optical techniques. CGHs are generated entirely in digital form...

Concave and convex spherical mirrors are types of curved mirrors that have surfaces shaped like segments of spheres. These mirrors are commonly used in optics for various applications, including...

A confocal resonator, also known as a confocal cavity or confocal laser resonator, is a type of optical resonator configuration used in laser systems. The term confocal in this context refers to the...

Hardware installed on fiber cable ends to provide cable attachment to a transmitter, receiver or other cable. Usually a device that can be connected and disconnected repeatedly.

The apparent difference in brightness between light and dark areas of an image. For a light target against a dark background, contrast is computed as follows: where Lt is the luminance of the...

The simplest lens in which all primary aberrations may be corrected. It consists of two positive crown elements on either side of, and spaced away from, a negative flint element.

A compound prism formed by cementing together two 30° prisms, one of right-handed and one of left-handed quartz. It has good ultraviolet-transmitting qualities and no double refraction.

Law relating the illuminance (or irradiance) of a surface to the cosine of the angle, q, between the normal to the surface and the direction of the incident wave.

The least angle of incidence at which total internal reflection takes place. The angle of incidence in a denser medium, at an interface between the denser and less dense medium, at which the light is...

Illumination in which the light source is imaged at the object.

The axes of symmetry in a crystal structure. See also biaxial crystal; uniaxial crystal.

A lens aberration that causes a flat object surface to be imaged onto a curved surface rather than a plane.

A lens aberration in which the focal length varies radially outward from the center of the field. It has the effect of making a straight tangential line in the object appear curved in the image,...

Custom lapping and polishing services involve specialized processes used to improve the surface finish and dimensional accuracy of components to meet specific requirements or standards. These...

A custom optic refers to an optical component that is designed, manufactured, and tailored to meet specific requirements or applications. These optics can include lenses, mirrors, prisms, filters, or...

A cylindrical lens is an optical component that has different curvatures along its two orthogonal axes, resulting in a shape resembling a cylinder. Unlike spherical lenses, which have the same...

A system incorporated into fiber optic data communications characterized by several spatially distributed terminals that are served with the same multiplexed signal.

A quantitative measurement of the coherence of a light source; equal to the visibility (V) of the fringes of a two-beam interference test: where Imax equals the intensity at a maximum of the...

The number of unique ways in which a part can move in an alignment system. In static alignment, there are six: one in the direction of and one in rotation about each of the X, Y and Z axes. In...

The range of image distances that corresponds to the range of object distances covered by the depth of field.

Design and engineering consulting services refer to professional services provided by specialized firms or individuals to assist clients in various aspects of product development, system design, or...

A detector array refers to a collection of individual detector elements arranged in a two-dimensional grid or matrix format. Each element within the array is capable of detecting electromagnetic...

A detector-Dewar assembly typically refers to a combination of a detector and a Dewar flask used in scientific instruments, particularly in the field of infrared spectroscopy or other applications...

Diamond turning, also known as diamond machining or diamond cutting, is a precision machining process used to produce high-quality optical surfaces and components with extremely tight tolerances. It...

Diamond turning refers to a precision machining process used to produce complex optical components, particularly lenses and mirrors, from materials such as metals, plastics, and crystalline materials...

A dichroic coating, also known as a dichroic filter or dichroic mirror, is an optical coating designed to selectively transmit or reflect certain wavelengths of light while simultaneously absorbing...

Dichroism refers to the property of certain materials to exhibit different colors or absorbance of light depending on the direction of light propagation or polarization. The term is commonly used in...

As a wavefront of light passes by an opaque edge or through an opening, secondary weaker wavefronts are generated, apparently originating at that edge. These secondary wavefronts will interfere with...

A diffraction grating is an optical component consisting of a surface with a periodic structure of equally spaced, parallel grooves or rulings. These rulings act as an array of closely spaced slits...

Optical elements that use diffraction to control wavefronts. Diffractive optical elements include diffraction gratings, surface-relief diffractive lenses, holographic optical elements and...

A digital camera is a device that captures and records still images or video in digital format. Unlike traditional film cameras, which use photographic film to capture and store images, digital...

A diode laser is a type of laser that uses a semiconductor diode as the active medium to generate coherent light. Semiconductor diodes are electronic devices that conduct electricity primarily in one...