function [df] = FOVtof(dFOV, dSensorSize)
Description: Returns the focal length given the FOV and the sensor size. Remember that DAR = ImageSizeH/ImageSizeV, NOT FOVh/FOVv.
Out parameters:
- df = Focal lentgh [long units] (Col vector).
In parameters:
- dFOV = Field of view (horizontal or verical) [degree] (Col vector)
- dSensorSize = Size of image sensor (horizontal or verical) [long units] (Col vector)