Thin Lens Equation Calc

Thin Lens Calc. is the essential optics calculator for students, teachers, and engineers. Instantly solve the thin lens equation (1/f = 1/do + 1/di) for any unknown variable — focal length, object distance, or image distance — with real-time results and an interactive ray diagram. SOLVE ANY VARIABLE Select what you want to find, enter the two known values, and get the answer instantly. The app auto-calculates as you type or drag the slider, so you can explore how changing one parameter affects the others. INTERACTIVE RAY DIAGRAM Watch the ray diagram update live as you adjust values. See how light passes through converging and diverging lenses, where real and inverted images form, and how virtual images appear on the same side as the object. A visual way to build intuition for optics. STEP-BY-STEP SOLUTIONS Tap to reveal a full algebraic walkthrough of each calculation — from the starting equation through substitution, simplification, and unit conversion. Perfect for checking homework or learning the method. UNIT CONVERSION BUILT IN Switch freely between millimeters, centimeters, and meters for each field independently. The app handles all conversions internally so you never have to convert by hand. FEATURES • Solve for focal length (f), object distance (do), or image distance (di) • Live-updating ray diagram with object and image arrows • Step-by-step solution breakdown • Unit pickers (mm, cm, m, in, ft) per field • Adjustable decimal precision (0–10 digits) • Tap-to-copy results to clipboard • Save calculations to history (SwiftData) • Negative value support for virtual images and diverging lenses • Scientific notation for extreme values • No ads, no subscriptions, no internet required Built for physics students studying geometric optics, teachers preparing demonstrations, and anyone who needs a fast, reliable thin lens calculator on their iPhone or iPad. Thanks for your support, and please visit nitrio.com for more apps for your iOS devices.