| 摘要 |
The need for a Time Domain Integration line scan camera to change a workpiece's height in z to relocate an ROF (Range Of Focus) of fixed excursions about a fixed POLB (Plane Of Least Blur) is removed by making the location of the POLB movable, thus making the location of the associated ROF variable, while leaving the actual z height of the workpiece unchanged. This can be accomplished by ensuring that, for a desired new location of the POLB, the rate at which the physical Deltays transpire for the motion of the workpiece (which may be a PCA) matches the rate at which the optical Deltays are clocked for the TDI image sensor. That may be achieved by varying the value for physical Deltay as function of the POLB's location in z regardless of V<SUB>scan</SUB>, but while also adjusting V<SUB>scan </SUB>if that is necessary or desirable to keep such things as sensor cell exposure levels, and contrast from moving away from their optimum values.
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