3DOptix is described as 'Is changing the optical design process and revolutionizing the "optical system" simulation by harnessing the GPU cloud power with embedded 3D and CAD capabilities' and is an website. There are four alternatives to 3DOptix, not only websites but also apps for Windows and Self-Hosted. The best 3DOptix alternative is Zemax OpticStudio. It's not free, so if you're looking for a free alternative, you could try FRED. Other great sites and apps similar to 3DOptix are LightTools and CODE V Optical Design Software.
OpticStudio is the pinnacle of optical and illumination design software, an evolution engineered by Zemax. The intuitive user interface combined with a comprehensive array of features and unmatched functionality make OpticStudio the preferred design platform for engineers...
LightTools is a 3D optical engineering and design software product that supports virtual prototyping, simulation, optimization, and photorealistic renderings of illumination applications. Its unique design and analysis capabilities, combined with ease of use, support for rapid...
Design, optimize, and fabricate reliable imaging optics with the most powerful ray tracing and optical design software available
The Free Registry for ENUM and Domains (a.k.a. FRED) is open-source software for running domain and ENUM Registry, developed by the CZ.NIC, the .CZ and 0.2.4.e164.arpa domain Registry.
United States
Czechia
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Not in any way the same sort of software. 3DOptix is an optics simulator. FRED is for administrating a wed domain. They are about as alike as a boat and a book, or a spanner and a spaniel.