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Spatial frequency conversion

Author:admin   Date:2016-11-02   Hits:

The spatial frequency conversion table

  LW/PH LP/mm L/mm Cycles/mm Cycles/pixel LP/PH
LW/PH * 1 * picture / [2Height] / pictureHeight * picture / [2Height] Vert. pixels / [2 * #] /2,0
LP/mm * [2 * pictureHeight] * 1 * 2,0 * 1 * pixel pitch * [picture height]
L/mm * picture height * 0,5 * 1 * 0,5 [pixel * pitch / 2] * [pictureHeight/2]
Cycles/mm * [2 * pictureHeight] * 1 * 2,0 * 1 * pixel pitch * [picture height]
Cycles/pixel # vert. * [2 * pixels] Pixel / pitch * [2 / pixelPitch] Pixel / pitch * 1 [# * vert. pixels]
LP/PH * 2,0 / pictureHeight 2 / pictureHeight Picture / height # / vert. pixels * 1

NOTE 1 The pixel pitch in the direction is not the 45 diagonal same as in the vertical and horizontal directions. Therefore, the diagonal pixel pitch is used when applying this table to measurements in the diagonal directions.

NOTE 2 The pixel pitch is the pitch of pixels in the image file. The picture height and pixel pitch, in millimetres, used should be for the same magnification at which the lines per millimetre was determined, or vice versa.