LIGHT & OPTICS · LAB 26

Mirage simulation

Trace light through a temperature-stratified atmosphere and discover why distant objects appear displaced, stretched or inverted.

MIRAGE TYPEINFERIOR

Light bends toward denser, cooler air. Dashed lines show where the observer thinks the image is.

Actual raysBackward extensionsDirect sightlineTemperature layers

TEMPERATURE DIFFERENCE26 °C

surface inversion

INDEX GRADIENT−2.4 × 10⁻⁶ m⁻¹

n 1.00026–1.00028

RAY CURVATUREUPWARD

educational scale ×1

APPARENT IMAGEBELOW OBJECT

virtual and inverted

REFRACTION REGIMEINFERIOR

hot air near surface

WHAT TO NOTICE

A layered lens made of air

Air density—and therefore refractive index—changes with temperature. Rays curve continuously through many thin layers. Your eye assumes light travelled in a straight line, so it traces the arriving ray backward and places a virtual image where no object exists.

n ≈ 1 + 77.6 × 10⁻⁶ P/Td(nu)/ds = ∇n

Educational atmospheric-optics approximation. Vertical scale and ray curvature are exaggerated so the effect is visible.