OpticStudio 15.5 was free to download from our software library. The actual developer of the software is Zemax LLC. The software belongs to Photo & Graphics Tools.
From the developer:
OpticStudio is an optical and illumination design software tool. Design almost any optical or illumination system with OpticStudio, including:projection, binocular, binocular and freeform lenses; LEDs, backlight, display and solar systems; biomedical optical imaging systems; coherent laser and fiber optic systems and more.
You may want to check out more software, such as ShipRush for Endicia, Exercise Drawer or X Model Viewer, which might be similar to OpticStudio.