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Mantis shrimp eyes

ryanblakeley.net

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Re: Mantis shrimp eyes

#11

Post by mattkrause »

ilovecurl wrote: post #5
vmoore wrote: post #3

Obligatory Oatmeal comic about the Mantis Shrimp: https://theoatmeal.com/comics/mantis_shrimp

Obligatory Ze Frank vid: https://www.youtube.com/watch?v=F5FEj9U-CJM The Oatmeal claims that, "the mantis shrimp sees a thermonuclear bomb of light and beauty." This piece contradicts that claim: "Mantis shrimp have twelve photoreceptor classes. Humans have three. We derive a spectrum of colors through comparisons between our three classes; this is called the opponent process or opponency. Mantis shrimp do not do thi…

They actually do some comparison between colors, but it's implemented in a weird, alien way.

Instead of co-located and connected cones for different colors, they drag their eyes across a scene, so the comparison can happen across time instead, like a push broom sensor.

Re: Mantis shrimp eyes

#12

Post by philwebster »

e40 wrote: post #6
ilovecurl wrote: post #5

Earlier quoted context omitted.

Obligatory Ze Frank vid: https://www.youtube.com/watch?v=F5FEj9U-CJM The Oatmeal claims that, "the mantis shrimp sees a thermonuclear bomb of light and beauty." This piece contradicts that claim: "Mantis shrimp have twelve photoreceptor classes. Humans have three. We derive a spectrum of colors through comparisons between our three classes; this is called the opponent process or opponency. Mantis shrimp do not do thi…

I’d forgotten about Ze. Wow, what a wild ride his 365 day vlogging experiment was. It was the first and most precious thing I did everyday for almost a year.

His History of Mens Underwear video was one of the best: https://www.youtube.com/watch?v=LNRX8kfGgYg

Re: Mantis shrimp eyes

#14

Post by swyx »

> Polarized light usually oscillates in a fixed plane, but that plane can sometimes rotate, so light travels along a twisting helix.

wait what? they can bend light? make it not travel in a straight line? color me skeptical

Re: Mantis shrimp eyes

#15

Post by Sniffnoy »

swyx wrote: post #14

> Polarized light usually oscillates in a fixed plane, but that plane can sometimes rotate, so light travels along a twisting helix. wait what? they can bend light? make it not travel in a straight line? color me skeptical

The text here would appear to be confusing about what circular polarization means. Circular (or more generally, elliptical) polarization doesn't mean the light doesn't travel in a straight line.

Rather it means that the oscillations in the electrical (or equivalently, magnetic) field that the light consists of rotate around the axis that is the light's direction of travel, rather than staying in one fixed plane. The direction of travel stays constant though.

You might want to see the Wikipedia articles: https://en.wikipedia.org/wiki/Circular_polarization https://en.wikipedia.org/wiki/Elliptical_polarization

One way to think about this is to pick x and y directions perpendicular to the light's path of travel, and break down the light's oscillations into x and y components. Linear polarization occurs when these components are in phase with each other, and elliptical polarization occurs when they're not. When they're perfectly one quarter turn out of phase, you get circular polarization.

Re: Mantis shrimp eyes

#17

Post by swyx »

Sniffnoy wrote: post #15
swyx wrote: post #14

> Polarized light usually oscillates in a fixed plane, but that plane can sometimes rotate, so light travels along a twisting helix. wait what? they can bend light? make it not travel in a straight line? color me skeptical

The text here would appear to be confusing about what circular polarization means. Circular (or more generally, elliptical) polarization doesn't mean the light doesn't travel in a straight line. Rather it means that the oscillations in the electrical (or equivalently, magnetic) field that the light consists of rotate around the axis that is the light's direction of travel, rather than staying in one fixed plane. The…

ahh this makes sense. i was thinking of light as a stream of particles but this is about light-as-a-wave

Re: Mantis shrimp eyes

#18

Post by [deleted] »

swyx wrote: post #14

> Polarized light usually oscillates in a fixed plane, but that plane can sometimes rotate, so light travels along a twisting helix. wait what? they can bend light? make it not travel in a straight line? color me skeptical

[deleted]

Re: Mantis shrimp eyes

#19

Post by cultofmetatron »

swyx wrote: post #14

> Polarized light usually oscillates in a fixed plane, but that plane can sometimes rotate, so light travels along a twisting helix. wait what? they can bend light? make it not travel in a straight line? color me skeptical

its easy to make light follow a bend. thats how fiber optic cables work

Re: Mantis shrimp eyes

#20

Post by swyx »

cultofmetatron wrote: post #19
swyx wrote: post #14

> Polarized light usually oscillates in a fixed plane, but that plane can sometimes rotate, so light travels along a twisting helix. wait what? they can bend light? make it not travel in a straight line? color me skeptical

its easy to make light follow a bend. thats how fiber optic cables work

except theres nothing to bounce off of
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