Kayla Davis and Shynia Barksdale

1. Color (13.4)
By: Kayla Davis & Shynia Barksdale
3rd period

2. Objectives
❖Recognize how additive colors affect the
color of light
❖Recognize how pigments affect the color of
reflected light
❖Explain how polarized light is formed and
detected

3. Introduction
In this lesson we will learn how adding
certain colors affects the color of light,
how pigments affect the color of
reflected light, and how polarized
light is created and detected.

4. Additive Color Synthesis
A method of creating color by mixing various
portions of 2 or 3 distinctive stimulus colors
of light.
Primary Colors are Blue, Green, & Red.

5. ❖ Two Equal Primary colors create a Secondary
color :
1 Red
+ 1 Blue
= Magenta
1 Blue
+
1 Green
=
Cyan
1 Green
+
1 Red
=
Yellow
❖ Equal Stimulus Proportions of all three Primary
colors create White :
1 Red
+
1 Blue
+
1 Green
=
White
❖ Unequal Proportions of Two or Three Primaries
create other colors :
2 Red
+
1 Green
=
Orange
2 Green
+
1 Red
=
Lime
1 Blue
+
1 Green
+
4 Red
=
Brown

6. Pigments and Reflected
Light are molecules that Reflect one
❖Pigments
specific wavelength of light and Absorb all
others.
❖So, the color we see is a net effect of all the
light reflecting back at us.
➢
Ex) We see an Apple being RED because it has
absorbed every other color, and is reflecting the red
we see.

7. The Color of Light and Pigments Combine to create
Colors

8. HOW?
❖The sun emits a
radiation which we
see as the
“Rainbow”
❖The colors seen is
the Visible
Spectrum
❖(ROYGBIV)
➢
➢
➢
➢
➢
➢
➢
Red
Orange
Yellow
Green
Blue
Indigo
Violet

9. Reflection & Absorption
❖To be either reflected or absorbed depends
on what the wave hits to give it’s color.
❖Solids easily reflect light
❖For an object to be black, all light is
absorbed, no light is reflected

10. Reflection and Absorption
To be either reflected or absorbed depends on what to wave hits to give its color.
Reflection
❖ Solids easily reflect
light.
❖ Reflected light is the
color you see
Absorption
❖ Black objects absorb all
light, reflecting no light.
❖ Absorbed Light is the
colors you can't see

11. How Can We See Light?
❖Special rods in our eyes that are receptive to
light
❖Special cones in our eyes that are sensitive to
color
❖Not everyone can see the exact same color or
shade

12. Absorption Filters
❖Commonly manufactured from dyed glass or
pigmented gelatin resin.
❖Operate by decreasing light through
absorption of specific wavelengths.
❖The result depends on the physical thickness
of filter and amount of dye present.
http://micro.magnet.fsu.edu/primer/java/filters/absorption/

13. William Perkin
❖In 1856, accidentally discovered natural
substance “Aniline Purple” or “Mauveine” at
the age of 18
❖Learned the chemical produced beautiful
deep purple colored when dissolved in
alcohol to make dye products

14. Polarization Definition
❖Light waves or any other radiation are
restricted in one direction of vibration.

15. Characteristics of Polarization
Waves
❖They are basically a light wave that’s
vibrating in more than one plane.
❖Also are transverse waves that can be vertical
or horizontal.
❖They move in a linear line.

16. How is Polarized Light Formed?
Polarized light is created by a single vibration
electron emitting an electromagnetic wave
that is polarized on a single plane.
Simply, it’s single light wave reflecting in a
straight line. The way we might see this in
nature would be like a type of glare.

17. How Can We See Polarized Light?
The human eye lacks the ability to determine
the difference between randomly oriented
light and polarized light. It shows up as a
glare in our eyes. This is why we use polarized
sunglasses to reduce that glare.

18. How Polarized Sunglasses Work
Polarized sunglasses reduces the glare that is
seen on many surfaces. They use a special
filter that limits how much light can pass
through. The filters has to be aligned certain
way to allow light to pass and reduce the
bright glare from our eyes.

20. References
★
★ Additive Color Synthesis. (n.d.). COLOR THEORY. Retrieved October 29, 2013, from
http://home.bway.net/jscruggs/add.html
★ Davidson, M. W. (n.d.). Polarization of Light. Molecular Expressions . Retrieved October 29, 2013, from
http://micro.magnet.fsu.edu/primer/lightandcolor/polarizedlighthome.html
★ Davidson, M. W. (n.d.). Molecular Expressions. Absorption Filters. Retrieved October 29, 2013, from
http://micro.magnet.fsu.edu/primer/java/filters/absorption/
★ Hewitt, P. G. (2009). Light. Conceptual Physics (pp. 532-573). Upper Saddle River : Prentice Hall .
★ Light and Color . (n.d.). Resources for Science Learning. Retrieved October 29, 2013, from
http://www.fi.edu/color/

21. Questions???