Matrix Terms

Depth of Field

The distance allowing acceptable image definition to be maintained without refocusing.

Distortion

Distortion is a variation in magnification across the field of view

Field

Field of view for respective camera format (normally measured diagonally).

Magnification

A measure of the apparent differences in size between the object and image.

Matching Pixel Size

Matching pixel size is that which will permit the minimum feature size to overlap two pixels.

MTF (lp/mm)

A measurement of the ability of an optical system to reproduce (transfer) various levels of detail from the object to the image, as shown by the degree of contrast (modulation) in the image.

N.A. Image (high or low mag.)

Measurement at the image point of the largest cone of light rays that are exiting the optical system.

N.A. Object (high or low mag.)

Measurement at the object point of the largest cone or number of light rays that are entering the optical system.

Object to Image Distance (O-I)

Total distance from the object to the sensor inside the camera.

Resolvable Features (microns)

Measurement of lens system’s ability to image closely spaced points, lines and object surfaces as separate entities.

Working Distance (W.D.)

Clearance between object and lowest mechanical part of the system