Microscope types

Confocal

Uses a single photon to illuminate one plane of a specimen of at one time.

Two-Photon

Uses two photons to illuminate a specimen.

Super Resolution Light Microscopy

Uses two lasers lights to illuminate one nanometer at a time.

Scanning Acoustic

Uses a sound wave of specific frequency that travels through the specimen with a portion being reflected when it hits an interface within the material.

Transmission

Uses a beam electrons instead of light; electrons pass through the specimen; because of the shorter wavelength of electrons, structures smaller than 0.28um can be resolved. The image is two dimensional.

Brightfield

Uses visible light as a source of illumination; cannot resolve structures smaller than 0.2um; specimen appears against a bright background inexpensive and easy to use.

Darkfield

Uses a special condenser with an opaque disk that blocks light from entering the objective lens directly; specimen appears against a black background.

Differential interface contrast

Uses differences in refractive indexes to produce images. Uses two beams of light separated by prisms; the specimen appears colored as a result of the prism effect. NO staining requirws.

Fluorescence

Uses an ultraviolet or near-ultraviolet source of illumination that causes fluorescent compounds in a specimen to emit light.

Scanning

Uses a beam of electrons instead of light; electrons are reflected from the specimen; because of the shorter wavelength of electrons, structures smaller than 0.2um can be resolved. Image appears three dimensional.

Scanning tunneling

Uses a thin metal probe that scans a specimen and produces an image that reveals the bumps and depressions of the atoms on the surface of the specimen.

Atomic force

Uses a metal-and-diamond probe that is gently forced down along the surface of the specimen. Produces a three-dimensional image. No special prep.