Thin Lens Equation Calculator
1/f = 1/d_o + 1/d_i. Solve for any of focal length, object distance, image distance.
Result
di
15.0000 cm
Magnification M = -0.5000.
- f10.0000 cm
- d_o30.0000 cm
- d_i15.0000 cm
- M-0.5000
- Image typeReal (inverted)
Step-by-step
- 1/f = 1/d_o + 1/d_i.
- Solving for di: 15.0000 cm.
- Magnification = -d_i/d_o = -0.5000.
How to use this calculator
- Pick which to solve.
- Enter the other two.
- Read result + magnification.
About this calculator
Thin lens equation: 1/f = 1/d_o + 1/d_i. Sign conventions: f positive for converging (convex) lens, negative for diverging (concave). d_o positive for real object (in front). d_i positive for real image (other side); negative for virtual (same side). Magnification M = -d_i/d_o; |M| > 1 enlarged, |M| < 1 reduced. Negative M = inverted (real image), positive = upright (virtual). Used in cameras, telescopes, microscopes.
Frequently asked
Cartesian. f >0 converging. d_o >0 real object. d_i >0 real image. d_i <0 virtual (same side as object).
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