Color (North American English), or colour (Commonwealth English), is the characteristic of visual perception described through color categories, with names such as red, orange, yellow, green, blue, or purple. This perception of color derives from the stimulation of photoreceptor cells (in particular cone cells in the human eye and other vertebrate eyes) by electromagnetic radiation (in the visible spectrum in the case of humans). Color categories and physical specifications of color are associated with objects through the wavelengths of the light that is reflected from them and their intensities. This reflection is governed by the object's physical properties such as light absorption, emission spectra, etc.
By defining a color space, colors can be identified numerically by coordinates, which in 1931 were also named in global agreement with internationally agreed color names like mentioned above (red, orange, etc.) by the International Commission on Illumination. The RGB color space for instance is a color space corresponding to human trichromacy and to the three cone cell types that respond to three bands of light: long wavelengths, peaking near 564–580 nm (red); medium-wavelength, peaking near 534–545 nm (green); and short-wavelength light, near 420–440 nm (blue). There may also be more than three color dimensions in other color spaces, such as in the CMYK color model, wherein one of the dimensions relates to a color's colorfulness).
The photo-receptivity of the "eyes" of other species also varies considerably from that of humans and so results in correspondingly different color perceptions that cannot readily be compared to one another. Honey bees and bumblebees have trichromatic color vision sensitive to ultraviolet but insensitive to red. Papilio butterflies possess six types of photoreceptors and may have pentachromatic vision. The most complex color vision system in the animal kingdom has been found in stomatopods (such as the mantis shrimp) with up to 12 spectral receptor types thought to work as multiple dichromatic units.The science of color is sometimes called chromatics, colorimetry, or simply color science. It includes the study of the perception of color by the human eye and brain, the origin of color in materials, color theory in art, and the physics of electromagnetic radiation in the visible range (that is, what is commonly referred to simply as light).
Hi all, I‘m a recent member in this forum, very glad I found it. I am interested in light sensing and would like to know if there is any sort of light sensor whose response is manifested and measurable as an emmisson frequency similar to the frequency which is receiving or sensing. I am...
Ok I am really stumped and have no clue what I am missing...Here is the scenario. We have a mother and father who can be either $BB$, $Bb$ or $bb$.
The probability for both is:$$P(BB) = P(bb) = \frac{1}{4}$$
$$P(Bb) = \frac{1}{2}$$For the child one gene of the mother and one from the father is...
I was reading my book and it states that the lack of anti-symmetry in the total wave function of the Δ++ particle led to the introduction of the missing degree of freedom, or color. It states that free particles are colorless so they must be in color singlet states. From there, it just lists the...
Hello,
I am watching a video about spherical harmonics, and I am at the point where the color map is being shown for various values of ##l## and ##m##
My question is, what am I supposed to make of these plots? Pretty colors yes, but what do these things mean?
Hello,
I have heard many times that red lighting is good for imaging applications where the effect of ambient light needs to be reduced to a minimum. What is the theory behind this? Why does red light (vs. other colors) reduce the effect of ambient light?
Thank you.
hi pf!
So I'm drawing a picture in tikz and when I use the \shade command my lines are changing from black into the color. anyone know how to prevent this?
Thanks so much!
So I've been looking into the Law of Reflection with Specular and Diffuse Reflection. I understand that electrons have a certain vibrational frequency in objects, and if a light wave matches that, that color wouldn't be observed.
My question is, what if I took a red laser pointer and shined it...
8) Chimpanzees have much less visible white sclera than
humans. That is, their eyes are basically just black and brown. As
a result, what do scientists think the eyes of hominids looked like?
I realize its because of light waves reflecting off of everything, but what gives items their defined color. i.e. what keeps a banana from appearing red and an apple from appearing yellow. Do chemicals have constant way they react to light? why?
Things I don't understand:
What do they mean by "two spin-1/2 doublets and a spin-3/2 quadruplet"?
Why do they use the two flavours "+2/3e and -1/3e" ?
I'm doing a science fair project involving trying to explain color charge with the principles behind the Schrödinger cat thought experiment; However I'm having trouble finding the right principle. Its math project was well. Can anyone push me into the right direction
Some grade shool books claim that earthworm blood is red because it has hemoglobin, like ours.
Now right away you need to clarify what "hemoglobin" can mean. I'll start off by saying that IMO it is incorrect to use the word for every oxygen-transporting protein. Moreover it is false to assert...
If our eyes have only three types of color detector: one for red, blue and green, how do we perceive the color violet when we are looking at a spectrum?
If I am looking at the iphone or a TV or other device which effectively only emits combinations of pure red, blue and green light, I can see a...
http://www.nature.com/ncomms/2014/141223/ncomms6920/full/ncomms6920.html
'Mineralized rods and cones suggest colour vision in a 300 Myr-old fossil fish'
Management version: This pushes back in time the probable confirmation of the existence color vision.
Interesting point to note: Vertebrates...
If the color black absorbs all colors and reflects none and the color red absorbs all colors but reflects the color red and the color white is made up of all colors no absorption and all reflection how come the color white is not a mirror?
Hi, I am an optometrist, and electrical engineering students come to us worried about passing color vision portions of tests. Would a deep red colored contact lens such as X-chrom in one eye be helpful in passing a test or in your everyday work, or would it be too distracting and create more...
Hi, so I'm a first year neuroscience student at Carelton University in Canada. I had a little bit of a "revelation" with this topic recently after I understood it a bit better and I think this is really interesting. (If I understand it correctly!) We're learning about Kekule structures...
All else being equal, which color clothing would be best if you are exposed to a nuclear explosion (far enough away where you're not instantly killed, but still subjected to significant radiant energy)? Black or white?
It seems like black clothing would get hotter and could thus burn you by...
Homework Statement
Ok, so a friend of mine gave me this, I already failed, even tho I think I came pretty close, but I did something wrong along the way.
I have not done math in like 8 years so,... yea xD I feel like a failiure.
Since I hate not knowing the answer, and my friend won't tell me...
Hello, everyone.
What do the blue and pink color the rust indicator shown mean?
Let say, the mixture of potassium hexacyanoferrate(III) and phenolphthalein is the rust indicator. And we use to detect the rusting of an iron nail. And the result is: the tip, head region of the nail appear blue...
Hi,
I'm trying to figure out exactly what colors a white light (i.e. the Sun) would look like to an observer traveling at varying relativistic velocities. Yes, moving away from it - red shift. Moving towards it - blue shift. In more detail, the human eye has a limited varying-amplitude...
When looking through a triangular prism, I found that a black shape on a white back ground causes the blue end of the spectrum to be on the top of the black shape, and the red/yellow end is directed towards the bottom. The reverse is true for a white shape on a black background. Why is this?
I'm PhD research scholar, I prepared SnO sample of color black and kept my sample in desiccator some days back. But now it is converted into light yellow color. what might be the reason? any idea?
We have a standard assortment of balloons which is 6 different colors. We also have a 5 count bag of balloons which uses this standard assortment. Obviously you can get all 6 colors in a 5 count bag but my colleagues were curious about the other distributions.
The chances of only getting...
Hi pf, I just noticed that when light shines onto my tv screen (when it is off) you see thin bands of colors reflecting back (see picture attached). I just wondered why this was and also why it ONLY happens if DIRECT light (from a bulb or the sun) hits it. Also, you only ever seem to get 4...
I have a question about micrograph of steel.
In eutectoid steel, the pearlite exists as grains, within each colony the layers are oriented in essentially the same direction, which varies from one colony to another. The thick light layers are the ferrite phase, and the cementite phase appears...
Hi. I'm trying to replace a blown resistor on the control board of an electric oven. Unfortunately the color bands are partially darkened. Testing it with a multimeter gives an open-circuit in the resistor. I don't have the circuit diagram or the service manual for the appliance.
It looks...
Homework Statement
Find the error in the following proof that \all horses are the same color" 4.
Claim: In any set of h horses, all horses are the same color.
Proof: By induction on ##h##:
Base Case: For ##h = 1##. In any set containing just one horse, all horses are clearly the same color...
today i did a oil change on my outboard engine. i found out the oil is green, its normal? If yes, why the oil will be green color? because i fill the new oil is golden color.
I want to know color code for this resistor
---> 1KΩ \pm 10%
I have check in two sites. This sites showed me different color code for this resistor value.
Which one is right i don't know i am confused!
http://www.digikey.com/us/en/mkt/calculators/4-band-resistors.html
(this...
Hello guys ,
Can someone explain me why color of central circle in transmission case is bright whereas it is dark for the reflection case?
Thanks a lot,
Do molecules, atoms, and subatomic particles have color? If so, what? Is it even possible to determine if they do or not (Can electron microscopes see electrons?)? Is color even relevant at lengths this small? I would elaborate more but these questions are fairly straightforward.
Hi,
the "color" of quarks gives rise to the strong-force. I've read on some page (cannot remember where) that same-color repels and different color attracts. Additionally it was stated that the attractive force between color/anti-color is stronger than color/different color. But no ratios or...
Hello, as you might have guessed, my question revolves around thin film optics. My intention is: Given a two thin-film system residing on top of a semi-infinite (bulk) layer, how can I estimate the reflecting color (RGB preferably) when illuminated by white light? (Illustrated below).
I...
I've read previous threads that the color of our sun from outer space is white, but on Earth it is yellow because oxygen and nitrogen scatter the blue light. First, I am wondering if this is accurate. Second, if this is true, why do we see stars in the night sky as white? I would think the...
I was watching the video on youtube provided by monkeysee.com explaining the reason we see leaf green is because it does not absorb green light hence reflects green light to our eye.
So it means if some how we change the biological/chemical properties of a leaf we won't see it as green? In other...
Hi. I was reading Griffiths page 289 and I wasn't sure how the transition from Eq. (8.45) to (8.46) was allowed. What bothers me is factoring out the "color factors" since the c's are vectors, and generally the elements of these color factors are matrices. For example, how is it allowed to pull...
A jar contains red, blue, orange and green jelly beans. There are 20 of each color. How many jelly beens must be selected to guarantee that at least 3 are the same color?
The teacher got 9 as answer, but i do not know how she got this. Anybody would like to help please?
I have a question which asks me to estimate the color of a compound in white light. I can easily get the wavelength (hc/dE) as 460nm, which agrees with the book. Looking at a spectrum list that would seem to fall in the blue range, but the book is saying it would be orange because blue is...
Homework Statement
In a question I was asked, assuming a spectrometer reading of Hydrogen produced two strong spectral lines at 656.3nm and 410.1nm. And also assuming the diffraction grating had 500 lines/mm
What is the highest order of spectrum which can be fully observed , i.e value of m...
Suppose we consider a proton where we set the electric charge of the three quarks towards zero. At this point I assume we still would have the three quarks bound together?
Now reduce the strength of the strong force by say ten times. I was told in posts that the radius of the proton depends on...
If we could set the strong force to be ten times weaker (compared with the electromagnetic force) how much would the radius of the proton change if any?
In the limit that the strength of the strong force goes to zero does the proton radius approach some limit?
Thanks for any help!
can anyone explain me about the differences between color and strong force?Though there are four fundamental forces so from where does the color force come?
Homework Statement
A 400 nm light ray is traveling through a vacuum.
a.) Give the light’s speed, frequency and color.
speed = 3E8: Correct
frequency = 7.5E14: Correct
color = violet: Correct
b.) This light now passes into a material where n=1.6. Give the light’s speed, frequency, wavelength...