Introduction

Lentil is a Python library for modeling the imaging chain of an optical system. It was originally developed at NASA’s Jet Propulsion Lab by the Wavefront Sensing and Control group (383E) to provide an easy to use framework for simulating point spread functions of segmented aperture telescopes.

Lentil provides a framework for defining optical planes and combining them to model diffraction and other imaging effects. It can be used to create models with varying levels of complexity - from simple prototypes to extremely high-fidelity models of ground or space telescopes.

Lentil uses one or more Plane objects to numericlly model an optical system. A Wavefront object representing a discretely sampled monochromatic plane wave is then propagated from plane to plane using one of the available numerical diffraction propagation routines. The resulting complex field can be visualized, analyzed, or further propagated through an optical model. Finally, Lentil includes a number of additional tools for representing common imaging artifacts, modeling focal plane arrays including many common noise sources, and working with radiometric quantities.