# Physically-based simulation of rainbows

@article{Sadeghi2012PhysicallybasedSO, title={Physically-based simulation of rainbows}, author={Iman Sadeghi and Adolfo Mu{\~n}oz and Philip Laven and Wojciech Jarosz and Francisco J. Ser{\'o}n and Diego Gutierrez and Henrik Wann Jensen}, journal={ACM Trans. Graph.}, year={2012}, volume={31}, pages={3:1-3:12} }

In this article, we derive a physically-based model for simulating rainbows. Previous techniques for simulating rainbows have used either geometric optics (ray tracing) or Lorenz-Mie theory. Lorenz-Mie theory is by far the most accurate technique as it takes into account optical effects such as dispersion, polarization, interference, and diffraction. These effects are critical for simulating rainbows accurately. However, as Lorenz-Mie theory is restricted to scattering by spherical particles… Expand

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#### References

SHOWING 1-10 OF 70 REFERENCES

Computing the scattering properties of participating media using Lorenz-Mie theory

- 2007

This paper introduces a theoretical model for computing the scattering properties of participating media and translucent materials. The model takes as input a description of the components of a… Expand

Computing the scattering properties of participating media using Lorenz-Mie theory

- Mathematics, Computer Science
- ACM Trans. Graph.
- 2007

The results show that the theory is able to match measured scattering properties in cases where the classical Lorez-Mie theory breaks down, and it can compute properties for media that cannot be measured using existing techniques in computer graphics. Expand

Light scattering by hexagonal ice crystals: comparison of finite-difference time domain and geometric optics models

- Physics
- 1995

We have developed a finite-difference time domain (FDTD) method and a novel geometric ray-tracing model for the calculation of light scattering by hexagonal ice crystals. In the FDTD method we use a… Expand

Simulating rainbows in their atmospheric environment.

- Medicine
- Applied optics
- 2008

The peaks of the scattering phase function for raindrops that correspond to the geometric optics rainbow are so pronounced that rainbows remain bright and colorful for optically thick rain shafts seen against dark backgrounds, but the bows appear washed out or vanish as the background brightens or where the rain shaft is shaded by an overhanging cloud. Expand

Physically-based simulation of rainbows

- Mathematics
- 2012

In this article, we derive a physically-based model for simulating rainbows. Previous techniques for simulating rainbows have used either geometric optics (ray tracing) or Lorenz-Mie theory. Lorenz...

Light scattering by nonspherical particles : theory, measurements, and applications

- Environmental Science, Physics
- 1998

This book provides a most welcome review and grounding in the necessary basics of the subject, and will prove to be a most useful addition to the literature in the ever-expanding field of light scattering. Expand

Simulating rainbows in their atmospheric environment

- Physics
- 2008

Light and color of geometric optics rainbows are simulated in their atmospheric environment. Sunlight passes through a molecular atmosphere with ozone and an aerosol layer near the ground to strike a… Expand

Simulation of rainbows, coronas, and glories by use of Mie theory.

- Physics, Medicine
- Applied optics
- 2003

Mie theory can be used on modern personal computers to produce full-color simulations of atmospheric optical effects, such as rainbows, coronas, and glories, and comparison of such simulations with observations of natural glories and cloudbows is encouraging. Expand

Efficient Rendering of Atmospheric Phenomena

- Physics, Computer Science
- Rendering Techniques
- 2004

A multiple-model lighting system that efficiently captures gradual blurring of chromatic atmospheric optical phenomena by handling the gradual angular spreading of the sunlight as it experiences multiple scattering events with anisotropic scattering particles. Expand

Mie theory, airy theory, and the natural rainbow.

- Medicine, Physics
- Applied optics
- 1998

Compared with Mie scattering theory, Airy rainbow theory clearly miscalculates some monochromatic details of scattering by small water drops, yet when monodisperse Airy theory is measured by perceptual standards such as chromaticity and luminance contrast, it differs very little from Mie theory. Expand