Optiland: Open-Source Optical Design Software in Python

Optiland (Harrison, 2026b) is an open-source optical design package written in Python.It offers a comprehensive platform for the design, analysis, and optimization of complex optical systems, catering to a wide audience from professional engineers and researchers to students and educators.Optiland handles a broad range of optical systems, from classical refractive and reflective designs to advanced freeform and computational optics.Core features include sequential ray tracing, a rich library of surface types (spherical, aspheric, freeform), optimization and tolerancing support, and a suite of analysis tools for evaluating optical performance (e.g., spot diagrams, wavefront analysis, modulation transfer function).A key feature of Optiland is its dual-backend architecture, which allows users to switch between a NumPy (Harris et al., 2020) backend for fast CPU computations and a PyTorch (Paszke et al., 2019) backend for GPU acceleration and automatic differentiation.This enables the integration of Optiland with machine learning workflows and gradient-based optimization, as all calculations are differentiable.Optiland also includes a graphical user interface (GUI) for interactive design and analysis.Further documentation is available online (Harrison, 2026a).