Microscope Terms and Definitions | College Biology Lab I

Light microscope

type of microscope that commonly uses visible light and a system of lenses to generate magnified images of small objects

Total magnification

the magnifying power of the objective multiplied by the magnifying power of the objective lens

Resolution

the smallest distance between two points that can still be distinguished as separate entities

Light source

the source of light that illuminates the specimen being viewed

Condenser lens

lens system in a microscope that focuses light from the microscope's light source onto the specimen being viewed

Contrast

the ability to distinguish between a sample and its background

Condenser iris diaphragm

controls the amount of light that passes through the condenser and into the specimen. It's located below the stage of the microscope, above the condenser

Ocular

the part of a microscope that magnifies the image produced by the objective lens so that it can be seen by the human eye

Objective lens

a lens or group of lenses that creates the first magnified image of a sample

Stage

the flat surface where a specimen is placed for observation

Field of view

the total circular area you can see through the microscope. Usually expressed as the diameter of the field of view

Ocular micrometer

a glass disk with a calibrated ruler etched on it that is used to measure the size of microscopic objects under a microscope. It's placed in the eyepiece of the microscope

Depth of field

resolution in the z-plane. The range of depth that is in focus

Wet mount

a glass slide with a specimen suspended in a drop of liquid, usually water, that is used for microscopic examination

Dissecting microscope

a microscope that produces a magnified, three-dimensional image of a specimen or sample. It's used for examining or dissecting biological specimens

Working distance

the distance between the front of the objective lens and the specimen surface when the specimen is in focus