Topic
Green flash
About: Green flash is a research topic. Over the lifetime, 62 publications have been published within this topic receiving 452 citations. The topic is also known as: green ray.
Papers published on a yearly basis
Papers
1 Sep 1978
TL;DR: Interaction of cone signals was studied by measuring increment thresholds for combinations of green and red flashes on a yellow adapting field and the cancellation effect for the simultaneous incremental flashes largely disappeared when the flashes were exposed briefly or reduced in size.
Abstract: Green and red flashes of light will differentially stimulate the middle- and long-wavelength sensitive cones. Interaction of cone signals was studied by measuring increment thresholds for combinations of green and red flashes on a yellow adapting field. When the yellow adapting field was at 10.000 trolands (td), green and red incremental flashes (1 degree, 200-msec duration) produced cancellation when presented simultaneously and facilitation when presented sequentially. A green incremental flash (1.15 degrees, 200 msec, 5000-td adaptation field) and red decremental flash, or vice versa, produced facilitation when presented simultaneously. The results can be explained by color-differencing, opponent-mechanisms. The cancellation effect for the simultaneous incremental flashes largely disappeared when the flashes were exposed briefly (10 msec) or reduced in size (0.04 degrees). It is unlikely that the stimuli were exclusively detected by achromatic, luminance channels, as suggested by previous work, since observers could partially distinguish the hue of threshold flashes of 570- and 590-nm light (0.04 degrees, 10 msec) on a bright yellow field.
57 citations
TL;DR: In this article, the authors considered rainbows, sparkling reflections on water, mirages, green flashes, earthlight on the moon, glories, daylight, crystals and the squint moon.
Abstract: Optical phenomena visible to everyone have been central to the development of, and abundantly illustrate, important concepts in science and mathematics. The phenomena considered from this viewpoint are rainbows, sparkling reflections on water, mirages, green flashes, earthlight on the moon, glories, daylight, crystals and the squint moon. And the concepts involved include refraction, caustics (focal singularities of ray optics), wave interference, numerical experiments, mathematical asymptotics, dispersion, complex angular momentum (Regge poles), polarisation singularities, Hamilton’s conical intersections of eigenvalues (‘Dirac points’), geometric phases and visual illusions.
52 citations
22 Apr 2004
TL;DR: A full solution to the global illumination problem is introduced, based on what is called curved photon mapping, that can be used to simulate several natural atmospheric phenomena and a model of the Human Visual System to display images in a more realistic way, taking into account how the authors perceive luminances in a real-world scene.
Abstract: Several natural phenomena, such as mirages or the green flash, are owed to inhomogeneous media in which the index of refraction is not constant. This makes the light rays travel a curved path while going through those media. One way to simulate global illumination in inhomogeneous media is to use a curved ray tracing algorithm, but this approach presents some problems that still need to be solved. This paper introduces a full solution to the global illumination problem, based on what we have called curved photon mapping, that can be used to simulate several natural atmospheric phenomena. We also present a model of the Human Visual System (HVS) to display images in a more realistic way, taking into account how we perceive luminances in a real-world scene. This is of special interest in the green flash effect, where some of the perceived green is owed to bleaching of the photoreceptors in the human eye.
20 citations
TL;DR: In this article, a combination of extensive observations and simple theory suggests that this refractive structure is formed by gravity waves which have wavelengths between about 0.2 and 2.0 kilometers.
Abstract: There has long been speculation about why the green flash can be seen on one day, while on another apparently similar day it cannot. Although the green flash can be produced by a number of different refractive structures in the atmosphere, only one is of consequence when the viewing is done over the irregular terrain of most land surfaces. A combination of extensive observations and simple theory suggests that this refractive structure is formed by gravity waves which have wavelengths between about 0.2 and 2.0 kilometers. In the atmosphere such waves derive their energy from wind shear and are the same waves that are associated with clear air turbulence. This model not only explains the frequent observations of multiple green flashes, but also, by demonstrating a dependence on atmospheric dynamics, it accounts for the variability in the occurrence of the green flash on otherwise comparable days.
15 citations
12 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2020 | 1 |
| 2018 | 4 |
| 2017 | 1 |
| 2015 | 3 |
| 2014 | 2 |
| 2013 | 1 |