Review of Chapters 1,2 & 3

System of Units and Notations Metric System Length: meters (m) Time: seconds (s) Mass: Kilograms (Kg) Powers of 10 Kilo, Mega, Giga, Tera Mili, Micro, Nano, Pico, Femto, Atto,…

Fundamental Properties of Light Chapter 1 Fundamental Properties of Light

Why do we see things?

Properties of Light How does it travel? How fast does it travel? What is it that travels? Is it wave, particle, or just rays?

Light travels in a straight line

Light travels in a straight line The intensity varies with the square of the distance

(example: comets tail is always facing away from the sun) Light has momentum (example: comets tail is always facing away from the sun)

Reflection

Refraction

Diffraction silver lining

Light is a Wave What is a wave?! distance Harmonic wave: wavelength Frequency (Hertz) Velocity (300,000,000 meters/sec) Wavelength (meters)

amplitude z frequency or wavelength z phase z

Wavefront

Light has color!! Color of the light depends on its wavelength …..

*Ripple Tank Waves http://www.cbu.edu/%7Ejvarrian/applets/waves3/ripple.htm * Longitudinal and Transverse Waves -2 http://acad.ursinus.edu/%7Emtakats/gifcat/wavedemo.html *Waves, ElectroMagnetic http://microscopy.fsu.edu/primer/java/electromagnetic/index.html *Oscillating Charge Field http://www.colorado.edu/physics/2000/applets/fieldwaves.html

Electromagnetic Spectrum

Visible Light Spectrum

Light sources (thermal) *Color Temperature (Vase) http://microscopy.fsu.edu/primer/java/colortemperature/index.html *Black Body http://jersey.uoregon.edu/vlab/PlankRadiationFormula/index.html

Fluorescent Lamp *Phosphorescence: E&M Radiation (Joblonski Diagram) http://microscopy.fsu.edu/primer/java/jablonski/index.html

n Index of Refraction v= c/n Velocity of light in vacuum Characterizes the response of a medium to light (electromagnetic field) wavelength Velocity of light in vacuum Velocity of light in a medium= Index of Refraction v= c/n

Geometrical Optics (Chapter 2) When objects are much larger than the wavelength Light Rays (Ray Optics)

Shadows *Shadow-point source *Shadow: Extended Source http://www.techxhome.com/lightsite/optics/shadows/pointShadow.html *Shadow: Extended Source http://www.techxhome.com/lightsite/optics/shadows/extendedShadow.html

Solar Eclipse: Aug. 11 1999 Earth Moon SUN

The Lunar Eclipse

Pinhole Camera *Pinhole Camera http://www.techxhome.com/lightsite/optics/pinholes/pinhole.html

Depth of Image and more 2 pinholes

Reflection *Oscillating Charge Field http://www.colorado.edu/physics/2000/applets/fieldwaves.html

Law of Reflection N i r R I air glass or mirror Reflected ray (R ) lies in the plane defined by incident ray (I) and surface normal (N) R makes an angle r that is equal to incident angle I. R lies on the opposite side of of N as incident ray I

Mirrors Why metals reflect light? Why do they appear certain color? Why can we listen to radio stations far away? (plasma frequency) Silvered and half-silvered mirrors First-surface and second-surface mirrors *Oscillating Charge Field http://www.colorado.edu/physics/2000/applets/fieldwaves.html

Reflectivity (how much is reflected?) Grazing Incidence Reflection (glass windows, water surfaces, waxed floors, etc.)

Who sees me in the mirror?! image (field of view) Simply apply law of reflection and trace the rays…

Sun Pillars and Sub Suns

Ice Crystals

Sub Sun

http://www.members.tripod.com/~regenbogen/englisch/atlas.htm

Sun Pillar

Multiple Reflections Example: Second Surface Mirrors

Corner Reflectors Retroreflectors

Refraction Recall: velocity of light v= c/n

*Refraction 1 http://microscopy.fsu.edu/primer/java/refraction/index.html http://wigner.byu.edu/LightRefract/LightRefract.html http://www.techxhome.com/lightsite/optics/refraction/boyFish.html Fish Tank

Material Refractive Index (n) Air 1.0003 Examples Material Refractive Index (n) Air 1.0003 Water 1.33 Glycerin 1.47 Immersion Oil 1.515 Glass 1.52 Flint 1.66 Zircon 1.92 Diamond 2.42 Silicon 4

Law of Refraction N i I Air (for example) n1 glass or water or … n2 R The Refracted ray (R ) lies in the plane defined by Incidence ray (I) and surface Normal (N) The Refracted ray (R ) lies on the opposite side of N as the incident ray I, and The Refracted ray (R ) makes an angle r that satisfies the Snell’s law: Angle of Incidence  Index of refraction in medium 1 almost equals to Angle of Refraction  Index of refraction in medium 2 (for small angles)

Snell’s Law (exact) c a  Sine of an angle

Now, consider this ….

Total Internal Reflection *Total Internal Reflection (Optical Fiber) http://www.techxhome.com/lightsite/optics/refraction/fiberOptic.html

Total Internal Reflection

Prisms as perfect reflectors: See Fig. 2.56 in the Text

Brilliance (TIR), Fire (dispersion) and Flash Diamond Brilliance (TIR), Fire (dispersion) and Flash

Refraction in Nature Mirages, Rainbows, Halos, Sun Dogs….

Mirages and Atmospheric Distortions sunset mirage

Mirage

Dispersion Refractive Index varies with Wavelength : n() Dispersion in a prism * Prism Refraction http://microscopy.fsu.edu/primer/java/prism/index.html http://www.techxhome.com/lightsite/optics/refraction/monoPrism.html refraction & refl. http://www.techxhome.com/lightsite/optics/dispersion/whitePrism.html dispersion

Rainbow

Rainbow *Rainbow http://www.phy.ntnu.edu.tw/java/Rainbow/rainbow.html http://www.techxhome.com/lightsite/optics/dispersion/raindrop.html rain drop

Ice Crystals

Sun Dogs

Halos

22 degree halo

22 degree halo

Chapter 3 Mirrors and Lenses Read 3.1, 3.2, 3.3 (A, B, C* , D), 3.4, 3.5** * Anamorphic Art ** Aberrations

Flat mirror revisited virtual image Read Text about the Kaleidoscope

(simply apply the law of reflection) Spherical Mirrors Where is the image? What is the field of view? Ray Tracing (simply apply the law of reflection)

Reflection in Curved Mirrors Convex and Concave Mirrors

axis O C F center focal point Paraxial Rays: Rays that are close to the axis

Ray Rules for a Convex Mirror Ray Rule 1: All rays incident parallel to the axis are reflected so that they appear to be coming form the the focal point, F. Ray Rule 2: All rays that (when extended) pass through center C are reflected back to themselves. Ray Rule 3: All rays that (when extended) pass through F are reflected back parallel to the axis.

C F O 1 C F O 3 C F O 2

Locating the Image Mirrors *Concave Mirrors http://www.techxhome.com/lightsite/optics/mirrors/sphereMirror.html *Concave Lens: virtual image *Convex Mirrors http://www.techxhome.com/lightsite/optics/mirrors/mirrorAberr.html spherical aberration

“Hand with Reflecting Globe” M. C. Escher, “Hand with Reflecting Globe” Fig 3.9

Concave Mirror axis O C F center focal point

Ray Rules for a Concave Mirror Ray Rule 1: All rays incident parallel to the axis are reflected so that they appear to be coming form the the focal point, F. Ray Rule 2: All rays that (when extended) pass through center C are reflected back to themselves. Ray Rule 3: All rays that (when extended) pass through F are reflected back parallel to the axis.

*Concave Mirrors http://www.techxhome.com/lightsite/optics/mirrors/sphereMirror.html

Spherical Lenses

Refraction at Curved Surfaces axis O C center n2 n1 Simply apply the laws of refraction

I R axis O C center n2 n1

Thin Spherical Lenses Converging Lens: focal length (f) is positive The focal length f depends on curvatures (R1 and R2) and the index of refraction (n) of the material (glass).

Thin Spherical Lenses Converging Lens: focal length (f) is negative

Examples of Converging and Diverging Lenses * Lens Action (Many Applets) http://microscopy.fsu.edu/primer/lightandcolor/javalens.html http://www.techxhome.com/lightsite/optics/lenses/principleRays.html principle rays

Ray Rules for Converging (and Diverging) Lenses Ray Rule 1: All rays incident parallel to the axis are deflected through F’ (or as if it came from F’) Ray Rule 2: All rays passing through the center of the lens Continue undeviated. Ray Rule 3: All rays that (when extended, if necessary) pass through F are deflected parallel to the axis.

Example: Ray Rules for a converging lens | F’ F | f f= focal length F’ F |

Power of a Lens in diopters in meters * Lens Action (Many Applets) http://microscopy.fsu.edu/primer/lightandcolor/javalens.html http://www.techxhome.com/lightsite/optics/lenses/principleRays.html principle rays

Spheres as Thick Lenses Examples: Water droplets (dew) Glass beads ..

Dew Heiligenschein: The Holy Light ! Heiligenschein (German for halo) occurs when sunlight falls on nearly spherical dew drops and refracted back toward the sun in the same direction as it enters. It appears as bright white light around the shadow of your head on a dew-covered lawn.

Glass Beads as Retroreflectors Scotchlite

Fresnel Lenses

Lens Aberrations Chromatic http://www.techxhome.com/lightsite/optics/lenses/chromAberr.html

Spherical Aberration

*Thick Lens (Spherical Aberration) http://www.cbu.edu/%7Ejvarrian/applets/lens3/thickl_z.htm http://www.techxhome.com/lightsite/optics/mirrors/mirrorAberr.html

Curvature, Coma

Astigmatism

Distortion

Exam I: Tuesday Oct. 3 Covers Chapters 1,2,3 The test will consist of essay type questions and multiple choice and short answer questions. You will be allowed a crib sheet (one standard size 8”x11.5” piece of paper with notes on both sides) Solutions will be posted on a bulletin board on the underground part of the Regner hall and placed in the class folder that can be checked out at the circulation desk of the Centennial Library. Bring a ruler, pen and/or pencil (No Calculators, No Text Books, No Notebooks)