Optics Glossary Of Terms

Front 1

Angle of incidence

Back 1

The angle formed between a ray of light striking a surface and the normal to that surface at the point of incidence

Front 2

Angle of Reflection

Back 2

The angle formed between the normal to a surface and the reflected ray. This angle lies in a common plane with the angle of incidence, and is equal to it.

Front 3

Angle of Refraction

Back 3

The angle formed between the reflected ray and the normal to the surface. This angle lies in a common plane with the angle of incidence.

Front 4

Aperature

Back 4

An opening or hole through which radiation or mater may pass. Aperture stop – A physical restraint that limits the diameter of the bundle of light allowed to pass through a lens

Front 5

apochromatic

Back 5

Describing a lens or optical system with very little chromatic aberration. In an apochromatic lens (also known as an apochromat) the chromatic aberration is completely cancelled out at three or more wavelengths, compared with two for a typical achromatic lens. Apochromats usually have at
least three optical elements, made from different types of glass

Front 6

Beam

Back 6

A bundle of light rays

Front 7

Beamsplitter

Back 7

An optical device for dividing a beam inot tow or more seperate beams

Front 8

Binocular

Back 8

An instrument having a pair of lenses, one for each eye that focuses on a single object as a magnifier

Front 9

Chromatic aberration

Back 9

The lens aberration resuting from the normal increase in the refractive index of all common materials toward the blue end of the spectrum

Front 10

C-mount

Back 10

This is an adapter used with various types of video or digital cameras. The C-mount adapter drops into the trinocular port of the microscope and has lenses built into it. The C-mount adapter is microscope-specific, meaning that the brand of the microscope and the brand of the C-mount adapter should match - this is because each C-mount adapter is created specifically for a microscope in order to
have the correct focal length for the camera. The C-mount adapter has threads on the end of it and connects directly to either a video or microscope digital camera.

Front 11

Diopter

Back 11

A unit of measurement used to describe the degree of refractive error with respect to nearsightedness, farsightedness, and astigmatism.

Front 12

Eyepiece

Back 12

Lens (or lens system) with which the eye observes the image formed by the microscope.  The eyepiece provides a magnification, a diopter correction, and an eyecup setting.

Front 13

Field of View

Back 13

Sometimes abrreviated FOV, this is the diameter of the circle of light that you see when looking into the microscope.  As the power increases, the field of view decreases.

Front 14

Interpupilliary Adjustment

Back 14

When using a stereo or binocular microscope, there must be an adjustment for the distance between the viewers eyes.

Front 15

Intermediate Image

Back 15

An image formed in space by a lens

Front 16

Parfocal

Back 16

This is a focus issue.  When changing from one viewing system or magnification to another, the new image should be either in focus or close enought so that you can refocus with only minor adjustments.   Most microscopes are parfocal.

Front 17

Resolution

Back 17

The ability of a lens system to show fine details of the object being observed

Front 18

T-mount

Back 18

A type of adapter used to mate still cameras (usually 35mm) to microscopes.  These are often used with SLR cameras and are used in combination with an SLR adapter for a microscope.