A web app for creating and simulating 2D geometric optical scenes. Our goal is to make it easy for students to build physical intuition by "playing around", for teachers to do dynamical demonstrations, and at the same time also include tools for more advanced usage.

• Simulate various light sources: ray, parallel/divergent beam, and point source
• Simulate reflection in linear or curved mirrors, which can be defined by a custom equation
• Simulate beam splitters and dichroic mirrors
• Simulate refraction in linear or curved interfaces, which can be defined by a custom equation
• Simulate ideal lens/mirror, which obey the lens/mirror equation
• Simulate spherical lens defined by front/back focal distances
• Simulate gradient-index material defined by a custom refractive index function
• Simulate mixture of colors, color filtering, and chromatic dispersion
• Simulate diffraction gratings.
• View extensions of rays to see if they converge to a virtual image
• View real images, virtual images, and virtual objects directly
• View images that can be observed from some given position
• Distance, angular, energy flow, and momentum flow measurements
• Draw irradiance map and export as CSV data
• Export as SVG diagram
• Create modularized combinations of optical elements with custom parameters.
• Use the simulator as a node module in your own project.

• Launch the Web App
• Gallery
• Documentation
• About

If you use this project in your research, please cite it using the metadata in the CITATION.bib file.

You can also include the URL https://phydemo.app/ray-optics in the citation. The URL will not change in the foreseeable future (at least until 2032).

Contributions are welcome. For the following types of contributions, no (or little) programming knowledge is required:

• New items in the gallery
• New translations
• New modules (as in Tools -> Other -> Import Modules)

See CONTRIBUTING.md for the tutorial.

To contribute code, you need to have some knowledge of JavaScript and module bundling. The code is written in ES6 and bundled with Webpack. The code structure is documented in the documentation. See the following section for installation instructions.

To install the project locally, you need to have Node.js installed. Then, run the following commands in the terminal:

git clone https://github.com/ricktu288/ray-optics.git
cd ray-optics
npm install
npm run build

After that, the entire content for the https://phydemo.app/ray-optics website will be in the dist folder. For example, you can open the dist/simulator/index.html file in your browser to run the simulator.

If an error occurs during the installation, some common reasons are:

• The version of Node.js is too old. You can update Node.js to version 18 or later.
• Some system dependencies for node-canvas are missing. You can find the instructions for installing the dependencies in the node-canvas repository.

The full build may takes about half an hour to complete due to the generation of the large numbers of images for the gallery. See the following section if you only want to build the simulator.

For development, you don't need to build the entire website every time some code is changed. Instead, you can run the following command to start a local server:

npm run start

which serves the simulator web app at http://localhost:8080, and is automatically reloaded when some code for the simulator is modified. However, this does not include other part of this project such as the home pages, gallery and documentation. The separate build commands are available for these pages:

# build translations
npm run build-translations

# build home pages, about pages, gallery (not including image generation), and modules pages.
npm run build-webpages

# build the node module version of the simulator, which is required for the image generation.
npm run build-node

# generate images for the gallery, which may take a long time.
npm run build-images

# build the web app version of simulator (unlike npm run start, this command builds the simulator in production mode)
npm run build-simulator

# build documentation
npm run build-docs

Note that npm run build is equivalent to running all the above commands.

If you add new translatable strings to src/translations/en.json, you can run the following command to synchronize the strings to other languages so that translators can see the new strings to translate:

npm run sync-translations

• src contains the source code for the project.
• src/simulator contains the source code for the simulator app. To understand the structure of the code, see the documentation for more information. The documentation is generated from the jsdoc comments in the code.
• src/simulator-node contains the source code for the node module version of the simulator.
• src/webpages contains the code for the home pages, about pages, templates for gallery and module pages, and the JSON files for the gallery and modules.
• locales contains the translations for the project. Currently it is only automatically built for the simulator app. The translations for the webpages, gallery, and modules pages are manually built.
• scripts contains the scripts for custom build steps.
• dist contains the built files for the project (the entire content for the https://phydemo.app/ray-optics website).
• dist-node contains the built files for the node module version of the simulator, which is required for the image generation, and can also be used in your own project.

The simulator can be used as a node module in your own project. The node module version of the simulator is built with the following command:

npm run build-node

After that, you can use the simulator in your own project by importing the module:

const { Scene, Simulator, sceneObjs, geometry } = require('path/to/ray-optics/dist-node/main.js');

See the documentation for more information about the API. For a usage example, see the image generation script.

Copyright 2016–2024 Yi-Ting Tu

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.