chapter 27 color
DESCRIPTION
Chapter 27 Color. Spectrum of Visible Light. Red Photon. Wavelengths & Photons. Particles of light, called photons, each have a wavelength. Yellow Photon. Green Photon. Blue Photon. Prism Spectrum. Newton’s Color Wheel. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/1.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Chapter 27Color
![Page 2: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/2.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Spectrum of Visible Light
![Page 3: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/3.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Wavelengths & Photons
Red Photon
Blue Photon
Green Photon
Yellow Photon
PrismSpectrum
Particles of light, called photons, each have a wavelength.
![Page 4: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/4.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Newton’s Color WheelPrism spectrum is a straight line, so why did Isaac Newton describe color using a circular wheel?
![Page 5: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/5.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Additive Color Wheel
SpectralColors
Not in the spectrum. How do we see these?
R
Y
B G
M
C
RedYellowGreenCyanBlueMagenta
![Page 6: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/6.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Adding Colored Lights
Stream ofred & green photons looks same as yellow photons(metamerism)
Theatrical lighting
or
YELLOW
Eye toBrain
Notice overlap of red, green, & blue is seen as whitewhite light
![Page 7: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/7.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Demo: Seeing YellowSodium lamps emit yellow photons
Color monitor can only emit red, green, and blue (RGB); creates other colors by selectively turning RGB pixels on or off.
![Page 8: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/8.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Trichromatic Theorists
Thomas Young (1773-1829) English physicist
Hermann von Helmholtz (1821-1894)German physicist
James Clerk Maxwell(1831-1879)Scottish physicist
![Page 9: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/9.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Simple Trichromatic TheoryYellow &
Redphotons
excite me
Yellow, Green &
Cyanphotons
excite me
Cyan &Blue
photons excite me
Inside your eye there are three receptors
MOECURLY
LARRY
![Page 10: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/10.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Trichromatic: Seeing YellowYellow &
Redphotons
excite me. I’M
EXCITED
Yellow, Green &Cyan photons
excite me.I’M EXCITED
Cyan & Bluephotons excite
me.Yawn.
Yellow seen when Curly and Larry excited, either by yellow photons or red & green photons.
MOE
CURLYCURLY
LARRY
![Page 11: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/11.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Trichromatic: Seeing MagentaYellow &
Redphotons
excite me. I’M
EXCITED
Yellow, Green &Cyan photons
excite me.Yawn.
Cyan & Bluephotons excite me.
I’M EXCITED
Magenta is seen by eye when Moe and Larry excited, which no single type of photon can achieve.
MOE
CURLYCURLY
LARRY
![Page 12: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/12.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Demo: Maxwell Color DiskDisk painted half red, half blue looks
magenta when rapidly spinning.
![Page 13: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/13.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Mixing Blue & Red Paint
Mixing paint or ink is different from adding colors together by light.
Mix of blue and red paint produces a blackish brown
![Page 14: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/14.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Trichromatic: Seeing WhiteWhiteYellow &
Redphotons
excite me. I’M
EXCITED
Yellow, Green &Cyan photons
excite me.I’M EXCITED
Cyan & Bluephotons excite me.
I’M EXCITED
White seen when all three very excitedGray seen when all three less excited
MOE
CURLYCURLY
LARRY
![Page 15: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/15.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Trichromatic: Color BlindnessRed , Yellow,
Green &Cyan photons
excite me.I’M EXCITED
Cyan & Bluephotons excite me.
Yawn.
MOE
CURLYCURLY
LARRY
Color blindness occurs if the eye is missing one of the three receptors. Other receptors try to compensate but cannot distinguish some colors.
Do I see red or green?
![Page 16: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/16.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Color Blindness
ClassificationIncidence (%)
Males FemalesAnomalous
Trichromacy 6.3 0.37
Protanomaly(Red-cone weak) 1.3 0.02
Deuteranomaly(Green-cone weak) 5.0 0.35
Tritanomaly(Blue-cone weak) 0.0001 0.0001
Dichromacy 2.4 0.03 Protanopia
(Red-cone absent) 1.3 0.02
Deuteranopia(Green-cone absent) 1.2 0.01
Tritanopia(Blue-cone absent) 0.001 0.03
Rod Monochromacy(no cones) 0.00001 0.00001
29 or 70? 21 or 74?
Weakness or absence of one of the three types of cones is the cause of color blindness, leading to a reduced ability to distinguish colors.
![Page 17: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/17.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Trichromatic: After-Image
First stare at RED
I’M EXCITED!Yawn.
Yawn.
MOECURLYCURLY LARRY
Me too, but tired.
ME TOO!
I’M EXCITED!
MOECURLYCURLY LARRY
Then stare at WHITE
Moe and Curly are excited so what color is seen?CYAN (light blue-green)
![Page 18: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/18.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Negative After-image
Stare, unfocused, at the red cross for 10 seconds then look at white wall
![Page 19: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/19.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Negative After-image
Cyan
![Page 20: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/20.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Negative After-image
![Page 21: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/21.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Negative After-image
Cyan Magenta Yellow
![Page 22: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/22.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Simple Additive Color WheelLARRY
MOE CURLY
Newton’s color wheel is a simple formulation of trichromatic theory.White
![Page 23: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/23.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Color Vision in the Eye
Three types of cones (color)One type of rod (B/W only)
![Page 24: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/24.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
CIE Hue-Saturation Diagram
Eye is not a perfectoptical instrument.
Color “wheel” isactually distortedcone shape.
Rim is full saturation,center is white
LARRY %
CU
RLY
%
50% Larry50% Curly0% Moe
33% Larry33% Curly33% Moe
![Page 25: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/25.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Spectral Reflectance Curves
When white light shines on an object, some photons absorbed, others reflected by the object’s surface.
White Red
![Page 26: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/26.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Name That Color
White Red Dark Brown(Burnt Sienna)
BLUE GREEN RED
0%
100% BLUE GREEN RED BLUE GREEN RED
![Page 27: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/27.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Name That Color
Bluish Green Bright Yellow Blue(Cobalt)
BLUE GREEN RED
0%
100% BLUE GREEN RED BLUE GREEN RED
![Page 28: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/28.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Subtractive Color
Absorbing filters or absorbing pigments remove colors from white light.
Check Yourself:Yellow = Red + GreenCyan = Blue + GreenYellow & Cyan filters (or pigments)combine to give … Overlapping color filters
![Page 29: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/29.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Check Yourself
A soap film absorbs red, green, or blue light, depending on the film’s thickness.
What colors do we see where red is removed?
Where green is removed?
Where blue is removed?
![Page 30: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/30.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Four Color Printing
Magenta Yellow Cyan Black
Magenta+ Yellow+ Cyan
All Four
Green balloon printed with mix of yellow and cyan inks
![Page 31: Chapter 27 Color](https://reader035.vdocuments.net/reader035/viewer/2022062222/56815f79550346895dce80ef/html5/thumbnails/31.jpg)
Apr 22, 2023 Physics 1 (Garcia) SJSU
Check Yourself
Magenta Yellow Cyan Black
Which inks are mixed for the bright red balloon and dark red dress?