Matrix.trace

raytracing.Matrix.trace(self, ray)

The ray matrix formalism, through multiplication of a ray by a matrix, will give the correct ray but will never consider apertures. By “tracing” a ray, we explicitly consider all apertures in the system. If a ray is blocked, its property isBlocked will be true, and isNotBlocked will be false.

Because we want to manage blockage by apertures, we need to perform a two-step process for elements that have a finite, non-null length: where is the ray blocked exactly? It can be blocked at the entrance, at the exit, or anywhere in between. The aperture diameter for a finite-length element is constant across the length of the element. We therefore check before entering the element and after having propagated through the element. For now, this will suffice.

Parameters:: ray (object of Ray class) – A ray at height y and angle theta
Returns:: rayTrace – A list of rays (i.e. a ray trace) for the input ray through the matrix.
Return type:: List of ray(s)

Examples

>>> from raytracing import *
>>> # M is an ABCD matrix of a lens (f=10)
>>> M= Matrix(A=1,B=0,C=-1/10,D=1,physicalLength=0,label='Lens')
>>> # R1 is a ray
>>> R1=Ray(y=5,theta=20)
>>> Tr=M.trace(R1)
>>> print('the height of traced ray is' , Tr[0].y,  'and the angle is', Tr[0].theta)
the height of traced ray is 5.0 and the angle is 19.5