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Source divergence specification

pupil editor

Each field point emits a bundle of rays whose divergence is specified by selecting one of the following options from the Pupil editor:

Entrance pupil diameter
Specify the diameter of the entrance pupil, which is the paraxial image of the stop as viewed by the on-axis field point.
Float by stop size
No need to specify a number. The source divergence will be chosen automatically based on the stop size. Specify a semidiameter on the surfaces page.
Object space numerical aperture (N.A.)
Specify the numerical aperture on the object side. This is the sine of the half angle of the source, multiplied by the index of refraction at the source.
Object cone angle (degrees)
Specify the angle in degrees between the real marginal ray and the system axis, for the on-axis field point.
Infinite conjugate image space focal ratio (f/#)
Specify the focal ratio or f-number of the lens assuming the object is at infinity. The focal ratio is the of the diameter of the exit pupil to the focal length of the lens.
Paraxial working focal ratio (f/#)
Specify the focal ratio of the lens with the object at working conjugate. This is the ratio of the diameter of the exit pupil to the distance between the exit pupil and the image plane.

See also