Computer-guided alignment III: description of inter-element alignment effect in circular-pupil optical systems.

We present an analytic description of the inter-element alignment effect of misaligned optical systems with circular pupils. The description shows that decenter and tilt produce lateral displacement of the field and pupil coordinates, whilst a despace directly modifies the aberration coefficients by perturbing paraxial distances and scale factors of the two coordinates. This reveals that a misaligned surface not only changes its aberration characteristics, but also affects those of subsequent surfaces, which is the essence of the inter-element alignment effect.

Computer-guided alignment II :Optical system alignment using differential wavefront sampling.

We present a differential wavefront sampling method for the efficient alignment of centred optical systems. Using the inter-element effects reported in our previous study, this method generates a linear symmetric matrix that relates the optical wavefront to misalignments within the system. The solution vector of this matrix equation provides a unique description of decentre and tilt misalignments of the system.

Computer-guided alignment I : Phase and amplitude modulation of alignment-influenced optical wavefront.

As the first part of a development programme on computer-guided alignment (CGA), we model the alignment influence on the optical wavefront in terms of the phase and amplitude modulation. This modulation is derived from the interaction between alignment parameters and influence functions, both expressed in complex form. The alignment influence model is used to approximate the ray-traced target wavefront of a randomly mis-aligned multi-element system.