Depth of Field (DOF)

DOF is a range of object distance, which the image appears to be sharp and focused.
Also a parameter describing the distance of imaging side ( sensor side) is called depth of focus. Tolerable level of blur is called Permissible Circle of Confusion, or Permissible COC.This represents the smallest diameter of a bundle of rays when being focused on an image plan. The diameter of Permissible COC will be defined by each application, pixel size of camera and the person who actually measures. The amount of DOF shown in this catalogue is given by:

Calculation of DOF
1) DOF = 2｛(Permissible COC x W.F#) / (Opt Mag.)²｝
2) DOF＝ Permissible COC / （NA x Opt. Mag）