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Note

This is the documentation for Finesse 3, which is in a alpha stage of development.

We are currently doing a major reorganisation and rewrite of the documentation. The current version may lack some information. Please refer to previous versions if needed.

Previous version of the documentation

• 3.0a33 (2025-05-15)

• 3.0a32 (2025-03-20)

• 3.0a31 (2025-01-23)

• 3.0a30 (2025-01-23)

• 3.0a29 (2024-11-14)

• 3.0a28 (2024-09-19)

• 3.0a27 (2024-07-23)

• 3.0a26 (2024-07-10)

• 3.0a24 (2024-06-16)

• 3.0a23 (2024-04-29)

• 3.0a22 (2024-04-03)

• 3.0a21 (2023-11-20)

• 3.0a20 (2023-11-15)

• 3.0a19 (2023-08-19)

• 3.0a18 (2023-08-17)

• 3.0a17 (2023-08-02)

• 3.0a15 (2023-07-24)

• 3.0a14 (2023-07-20)

• 3.0a12 (2023-07-18)

• 3.0a11 (2023-07-17)

• 3.0a10 (2023-07-17)

• 3.0a9 (2023-07-17)

• 3.0a8 (2023-06-02)

• 3.0a7 (2023-06-02)

• 3.0a6 (2023-03-11)

Overview

Finesse is a fast and easy to use Python-based interferometer simulation program. It uses frequency-domain optical modelling to build accurate quasi-static simulations of arbitrary interferometer configurations.

For convenience, a number of standard analyses can be performed automatically by the program, namely computing modulation-demodulation error signals, transfer functions, quantum-noise-limited sensitivities, and beam shapes. The optical system can be modelled using the plane-wave approximation or Hermite-Gauss modes, allowing the computation of optical systems like telescopes or the effects of mode matching and mirror angular positions.

Finesse is based on an object-oriented design and provides a large set of utility functions for ease of use when handling complex simulation tasks, for example:

• chained simulations,

• advanced plotting of outputs,

• automated simulations,

• the use of Jupyter notebooks to document simulation tasks,

• and much more!