Photonics Dictionary

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.

A form of high-power microscope objective.

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...

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...

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...

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...

A microscope eyepiece designed for use with apochromatic objectives. Since apochromatic objectives are undercorrected for lateral color, these eyepieces are overcorrected for that aberration.

A coverslip, also known as a cover glass or cover slip, is a thin and flat piece of transparent material typically made of glass or plastic. It is used in microscopy to cover a specimen mounted on a...

A microscope objective designed to be used without liquid between the cover glass and the objective, or, in the case of metallurgical objectives, between the objective and the specimen.

1. The focal point. 2. To adjust the eyepiece or objective of a telescope so that the image is clearly seen by the observer. 3. To adjust the camera lens, plate, or film holder so that the image is...

A form of a stereoscopic microscope having paired objectives, prisms and eyepieces, and invented by H. Greenough.

A microscope designed so that the specimen is located face down above the objective.

A Michelson-type interference microscope used to produce interference patterns of reflective specimens through the interference between light reflected by the specimen and that reflected by a...

In a microscope, the physical distance between the focal points of the objective lens and the eyepiece. The standard tube length for a microscope is typically 160 mm).

A specially designed microscope for observing the etched surface of a polished metal specimen. The specimen is often laid face down on a horizontal stage and observed from beneath, the illumination...

An instrument consisting essentially of a tube 160 mm long, with an objective lens at the distant end and an eyepiece at the near end. The objective forms a real aerial image of the object in the...

The liquid used in microscopy to fill the space between the high-power objective lens and the microscope slide in order to increase the numerical aperture (NA) or collecting power in object space of...

The lens located at the object end of a microscope tube. A wide range of objectives is available, including simple achromats, the color-corrected apochromats and the flat-field objectives. Objectives...

The optical element that receives light from the object and forms the first or primary image in telescopes and microscopes. In cameras, the image produced by the objective is the final image. In...

A form of high-power microscope objective where the space between the object and the first element is filled with an oil having the same index as that element. This form reduces losses, increases the...

A microscope equipped with a polarizer, an analyzer and a Bertrand lens to focus on the upper focal plane of the objective. It is used chiefly by mineralogists and crystallographers for...

Phase contrast microscopy is an optical microscopy technique that enhances the contrast of transparent and colorless specimens, making it possible to visualize fine details and internal structures...

A microscope that has an annular stop in the lower focal plane of the condenser, and a quarter-wave retarding and absorbing ring in the upper focal plane of the objective that just fills the image of...

A microscope that uses a reflecting objective; often used with ultraviolet or infrared radiation.

An image-forming system that uses mirrors rather than lenses. Such objectives are frequently used for astronomical telescopes and in ultraviolet microscopes.

In a microscope, the optical assembly that focuses light on the specimen and into the objective.

Wide-field fluorescence microscopy uses either naturally occurring structures or staining with fluorescent tags that are activated by specific wavelengths of light and then emits a different...