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Home/Optics & Light/Lens Simulator

Lens Simulator

Converging and diverging lenses with ray diagrams and image formation.

Thin lens (paraxial)

0.14 (rel.)
0.28
0.1
0.28

1/f = 1/d_o + 1/d_i , m = −d_i/d_o . Real images on the transmission side when d_i > 0. Dashed segments are backward extensions to a virtual image.

Shortcuts

  • •Switch converging / diverging
  • •Compare do to f for real vs virtual images

Measured values

f0.140(rel.)
d_i0.280
h_i-0.100
m-1.000
Imagereal, inverted
Screen focus error0.000rel.

About this model

Thin-lens ray tracing for converging and diverging lenses: principal rays, image location, and magnification sign conventions.

Who it's for: Geometric optics; sign rules and real vs virtual images.

Key terms

  • thin lens
  • focal length
  • magnification
  • real image
  • virtual image

How it works

Thin-lens ray diagrams use three principal rays: parallel to the axis then through the focal point; straight through the lens center; through the object-side focal point then parallel to the axis. The thin-lens equation links object distance, image distance, and focal length.

Key equations

1/f = 1/d_o + 1/d_i
m = h_i/h_o = −d_i/d_o