Dynamic range of Shack Hartmann sensor

The equation of dynamic range of Shack Hartmann sensor is:

\[\theta_{max} = \frac{\Delta s_{max}}{F} = \frac{d/2}{F} \] \(d\) is the lenslet diameter. \(F\) is the focal length of lenslet. Measurement sensitivity is \[ \theta_{min} = \frac{\Delta s_{min}}{F}\] The trade-off between the dynamic range and measurement sensitivity of a SHWS is: Increasing the dynamic range results in a decrease in measurement sensitivity and vice versa. \(\Delta s_{min}\) is the minimum detectable spot displacement. Typically it is determined by the pixel size of the photodetector, the accuracy of the centroid algorithm and the signal-to-noise ratio of the sensor.

In [1]:
import numpy
d = 63e-6 # in meter; pitch of micro lens array
F = 2.002e-3 # in meter; focal length of micro lenslet

DyRange = d/2/F
display(DyRange)
0.015734265734265736
In [ ]:
 

Leave a Reply

Your email address will not be published. Required fields are marked *