The Application Gallery features COMSOL Multiphysics® tutorial and demo app files pertinent to the electrical, structural, acoustics, fluid, heat, and chemical disciplines. You can use these examples as a starting point for your own simulation work by downloading the tutorial model or demo app file and its accompanying instructions.

Search for tutorials and apps relevant to your area of expertise via the Quick Search feature. Note that many of the examples featured here can also be accessed via the Application Libraries that are built into the COMSOL Multiphysics® software and available from the File menu.

Ray Optics Modulex

Double Gauss Lens Image Simulation

This example demonstrates how to import a bitmap which can be used to simulate an image using ray tracing. The example is based on the Double Gauss Lens tutorial from the Ray Optics Module Application Library. The first study has been modified so that the Spot Diagram "auto-focus" tool ... Read More

Two-Mirror Laser Cavity

In this model, two concave mirrors are placed at a distance and a ray is released from a point inside the cavity. Then the ray is traced for a predefined time period that is sufficiently long. Ray tracing continues until the predefined computation time has passed if the laser cavity is ... Read More

Sagnac Interferometer

This is a model of a simple Sagnac interferometer consisting of two mirrors and a beam splitter arranged in a triangle. The entire modeling domain rotates; as a result, the rays propagating in opposite directions in the triangle have different optical path lengths due to the Sagnac ... Read More

Newtonian Telescope

Newtonian telescopes, first invented in 1668 by Isaac Netwon, are still used today because of their low cost and simple design. Rays of light propagate from sources located at infinity, into the telescope. The rays reflect off a parabolic mirror, onto a flat mirror, and into the focal ... Read More

Total Internal Reflection Thin-Film Achromatic Phase Shifter (TIRTF APS)

The capability to alter the polarization of light is crucial to a wide variety of optical devices. For example, the polarization of light has a significant effect on the performance of optical isolators, attenuators, and beam splitters. By assigning a specific polarization to light, most ... Read More

Annular Ultraviolet Reactor with Particle Tracing

In this example, a simple ultraviolet (UV) water purification reactor is modeled using a combination of ray tracing, computational fluid dynamics, and Lagrangian particle tracking. First, the volumetric fluence rate is accumulated along rays released from the surface of the UV lamp using ... Read More

Newtonian Telescope Structural Analysis

This tutorial demonstrates a structural analysis of a simple telescope. The deformation of the telescope structure under gravity is examined and the effect on image quality is demonstrated. Read More

White Pupil Échelle Spectrograph

Échelle spectrographs are commonly used in astronomy for high-resolution analyses of stellar atmospheres and for precision Doppler velocimetry. This tutorial simulates a "white pupil" form of this instrument. It makes use of several parts from the COMSOL Part Library and demonstrates the ... Read More

The Penrose Unilluminable Room

An interesting question was raised in the 1950s by the mathematician Ernst Straus that, in an arbitrarily shaped empty room with side walls made of perfect mirrors, will a point light source always illuminate the whole room? This question was answered by the Nobel Prize-winning ... Read More

Bow-Tie Laser Cavity

This type is one of the most popular laser cavities. In particular, it is often used for the Ti-doped sapphire femto-second laser. The stability of the laser cavity is analyzed by releasing a ray inside the cavity and is traced for a predefined time period that is sufficiently long. ... Read More