Photonics Dictionary

An atomic force microscope (AFM) is a high-resolution imaging and measurement instrument used in nanotechnology, materials science, and biology. It is a type of scanning probe microscope that...

A scanning electron microscope (SEM) is a powerful imaging instrument used in scientific research, materials characterization, and various industrial applications. Unlike traditional optical...

A two-lens arrangement intended to image light into a microscope slide sample. The primary aberrations present are red and blue rings observed around the image focus.

Image of a uniform source through the sample of a microscope image system. Light from the sample plane is reimaged by the objective into the image plane.

An achromat, in the context of optics, refers to a type of lens or lens system designed to reduce chromatic aberration. Chromatic aberration is an optical phenomenon where different colors of light...

A form of high-power microscope objective.

An antireflection coating (AR coating) is a thin film or coating applied to optical surfaces, such as lenses or windows, to minimize unwanted reflections and increase the transmission of light...

The second adjustable iris diaphragm in an optical system. In the common microscope condenser system, it usually is located beneath the substage condenser on a transmitted light microscope. When the...

Aplanatic points refer to specific points in an optical system where certain aberrations, such as spherical aberration or coma, are minimized or eliminated. In an optical system, aberrations are...

An aplanatic surface is an optical surface that is specifically designed or shaped to minimize spherical aberration and coma. Spherical aberration is an optical aberration that occurs when light rays...

An apochromat, often referred to as an apochromatic lens or apochromatic objective, is a type of optical system designed to minimize chromatic aberration. Chromatic aberration occurs when different...

An aspheric lens is a type of lens whose surface profiles deviate from the traditional spherical shape. Unlike spherical lenses, which have a constant curvature across their surfaces, aspheric lenses...

An aspheric mirror is an optical mirror surface that deviates from the shape of a perfect sphere, having a non-spherical surface profile. Unlike traditional spherical mirrors, which have a curved...

Autofluorescence refers to the natural emission of fluorescence exhibited by certain biological structures or molecules when exposed to light. Unlike fluorescence that results from the application of...

A microscope to which a beamsplitter and illuminated reticle have been added to measure the radius of curvature of a spherical surface by locating both surface and center and calculating the distance...

An axicon is a type of optical component characterized by its conical shape and its ability to transform a collimated Gaussian beam of light into a ring-shaped beam with a gradually increasing...

Azimuthal polarization refers to a specific polarization state of light where the electric field vector of the electromagnetic wave points along the azimuthal direction (around the propagation axis)....

A ball lens is a small, spherical optical component typically made of glass or other transparent materials. It is characterized by its spherical shape, with both its front and back surfaces forming...

A beam shaper is an optical device or system designed to modify the spatial profile or intensity distribution of a laser or light beam. The goal is to transform the incoming beam into a desired shape...

A beamsplitter is an optical device used to divide a beam of light into two or more separate beams, typically by reflecting a portion of the incident light while transmitting the remainder....

Device used to measure the numerical aperture of a microscope, composed of a 14-mm-thick glass block with numerical aperture gradations carved onto its lower surface.

A band of light that appears along the outer edge of a transparent material under microscopic investigation and that moves toward higher refractive indices as the microscope's focus is raised, and...

A small convergent lens, located between the objective and eyepiece of a microscope, that focuses an image of the upper focal plane of the objective in the focal plane of the eyepiece. It is commonly...

The use of a short-duration electron beam to record high-speed events that occur in microscopic objects made of materials that emit visible fluorescence during electron bombardment. The method is...

A microscope designed with two eyepieces (oculars), permitting the use of both eyes when viewing through the instrument.

Birefringence is an optical property of certain materials that causes them to exhibit different refractive indices for light of different polarizations. In other words, when light passes through a...

A blue diode laser is a type of semiconductor laser that emits light in the blue wavelength range of the electromagnetic spectrum, typically between 400 and 500 nanometers. Diode lasers are compact,...

The illumination generally used in microscopy, whereby the specimen appears dark against a light background.

Brightfield refers to a type of microscopy and imaging technique in which the specimen is illuminated with a white light source, and the image is observed or captured against a bright background. In...

The behavior of microscopic solid particles suspended in a fluid, first observed by botanist Robert Brown in 1827 as a continuous random motion.

A telemicroscope in which a negative eyepiece is used to produce erect images.

A microscope that allows examination of a small crystal and conveniently provides linearly polarized object and reference beams so that, by suitable orientation of an anisotropic crystal, the optical...

A calcium indicator is a molecule that is sensitive to changes in calcium ion (Ca2+) concentrations in biological systems. These indicators are commonly used in various fields, including cell...

In analysis, the carbon layer that is evaporation-deposited on a specimen to protect and ready it for study by electron microscopy.

An oil immersion condenser used to permit only light that has been diffracted or dispersed by a microscope specimen to enter the microscope. It is used in dark-field microscopy.

A CCD camera, or charge-coupled device camera, is a type of digital camera that utilizes a CCD image sensor to capture and record images. CCD cameras are widely used in various applications,...

A microscope that can be used to observe and magnify microscope specimens while they are being centrifuged. The objective rotates near the periphery of the centrifuge head, and the ocular is...

The field of microscopy as applied to chemical problems and analysis.

Chirped mirrors are optical devices designed to manipulate the spectral properties of ultrashort laser pulses. They consist of multiple layers of dielectric coatings deposited on a substrate, where...

Chromatic aberration is an optical phenomenon that occurs when different wavelengths (colors) of light are refracted by a lens or optical system, leading to a failure to focus all colors to the same...

Cinematography performed with the use of a microscope to film the actions of microscopic specimens.

A type of compound microscope that uses three visible wavelengths to translate details produced by invisible radiation.

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...