# IOR - Index of Refraction > Index of Refraction reference for materials with interactive optical visualization. (iPhone/iPad app by Studio Orb, LLC.) - Source: https://appshunter.io/ios/app/ior-index-of-refraction/id302943148 (this page in markdown: same URL + `.md`) - Developer: [Studio Orb, LLC](https://appshunter.io/developer/302943151) - Category: Reference, Education - Price: $0.99 - Rating: 3.23/5 from 177 App Store ratings · 5 written reviews indexed - Age rating: 4+ - Requires: iOS 26.0 · 6 MB - Languages: English - Released: 2009-01-26 - Data updated: 2026-07-06 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/ior-index-of-refraction/id302943148/reviews.md ## What is IOR? IOR – Index of Refraction Reference Light bends. How much depends on the material. That number is the Index of Refraction — and getting it right is the difference between a render that looks like plastic and one that looks like glass, water, or diamond. IOR is a precision reference for anyone who works with light: 3D artists, VFX professionals, optical engineers, photographers, and students of physics and optics. 250+ Materials. Instantly Searchable. Browse a curated library covering gems, glass, metals, liquids, biological tissue, crystals, polymers, gases, and more — all cross-referenced against published scientific sources including NIST, USGS, and academic literature. Values are organized by category and fully searchable by name, type, or property. Interactive Optical Visualizer Every material comes with a live, physics-accurate display. Drag the IOR and angle sliders and watch how light bends in real time. Explore: • Snell's Law — angle of refraction as light crosses the boundary • Fresnel Reflectance — how much light reflects vs. transmits at any angle • Brewster's Angle — the angle at which reflected light is perfectly polarized • Total Internal Reflection — the critical angle beyond which light can't escape • Dispersion — how different wavelengths separate inside a medium Theory, Not Just Tables The Theory section walks through the optics fundamentals — Snell's Law, Fresnel equations, Brewster's Angle, TIR, and more - with interactive visualizers, equations, and curated video references. Whether you're learning the math or just need a refresher, it's all here. Built for 3D Artists Working in Blender, Maya, modo, LightWave, KeyShot, Cinema 4D, Houdini, or any renderer that exposes an IOR parameter - Arnold, V-Ray, Octane, Redshift, Cycles? IOR gives you the exact value you need for physically accurate materials. Stop guessing. Stop Googling. Look it up in seconds. Favorites & History Easily favorite any material for instant access. Tap and hold on any material in the lists, and it will add or remove a Favorites Star. Sort favorites by Category, A–Z, or IOR value. Your most-used materials are only one tap away. iPad & iPhone Optimized for both, Portrait and Landscape. ## Key features - 250+ searchable materials - Interactive optical visualizer - Snell's Law, Fresnel Reflectance, Brewster's Angle, TIR, Dispersion - Physics and optics theory section - Favorites and history - Optimized for iPad and iPhone ## Recent user reviews (5 of 5) All indexed reviews: https://appshunter.io/ios/app/ior-index-of-refraction/id302943148/reviews.md ### 5/5 — Excellent resource *2010-01-21, version 0* Just needs search or at least the letter list on the right side of the screen while scrolling. With those additions I'd happily pay a buck or two for this. ### 4/5 — Simple, Useful *2009-11-05, version 0* This app has a nice list of indicies. My only request would be a search function. ### 5/5 — Sweet *2009-04-24, version 0* This will come in handy when using Mental ray. Thanks! ### 4/5 — Great for nde (ndt) *2009-02-14, version 0* Cool little app. If you're in the nondestructive testing field it's nice to have. It would be cool if you could depict the refraction between two materials (besides the orb). Not complaining though. ### 5/5 — Easy to use!!!!! *2009-02-01, version 0* This is an Excellent application and thanks for offering it for free! ## Frequently asked questions about IOR ### What is the Index of Refraction (IOR) for? The Index of Refraction is a number that describes how much light bends when it passes from one medium to another. This value is crucial for creating physically accurate materials in 3D rendering, distinguishing between materials like glass, water, or diamond. ### How many materials are included in IOR? IOR includes over 250 materials, covering gems, glass, metals, liquids, biological tissue, crystals, polymers, and gases. These values are cross-referenced against published scientific sources like NIST and academic literature. ### Can I see how light bends with IOR? Yes, IOR features an interactive optical visualizer. You can adjust IOR and angle sliders to see how light bends in real time, demonstrating principles like Snell's Law, Fresnel Reflectance, Brewster's Angle, and Total Internal Reflection. ### Does IOR explain the theory behind light bending? Yes, the app has a dedicated Theory section that explains optics fundamentals such as Snell's Law, Fresnel equations, Brewster's Angle, and Total Internal Reflection. It includes interactive visualizers, equations, and curated video references. ### Is IOR useful for 3D artists? IOR is specifically built for 3D artists using renderers like Blender, Maya, Arnold, V-Ray, and Octane. It provides exact IOR values needed for physically accurate materials, eliminating guesswork and the need for constant online searches. ### How much does IOR cost? IOR is a paid application, available for $0.99. This one-time purchase grants access to all its features and data. ### Does IOR have ads? No, IOR is ad-free. As a paid application, it does not contain any advertisements, providing an uninterrupted user experience. ### What devices does IOR support? IOR is optimized for both iPhone and iPad, supporting both portrait and landscape orientations. It is compatible with devices running iOS. ## Version history (last 3 releases) ### 2.1 — 2026-04-26 It's an all-new app! A long awaited update from the initial version in 2009. ### 2.05 — 2026-04-23 All new app! A long awaited update from the initial version in 2009. ### 1.0 — 2009-01-26 No release notes. --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-07-06.*