Optical Physics

Optical Physics:

LABORATORY
+
Discussion

PHYS 307

Link to course schedule

Student discussion page: Piazza
Public chats via Mastodon

Optical Physics:

LABORATORY
+
Discussion

Center for Natural Science:

We have a windowless room
for
Discussion:
CNS room C102
Tues/Thur: 1:10-2:25PM

We have a windowless room
for
Lab:
CNS room WN007
Tues:6:30-9:00PM

Let there be LIGHT!


Gabe Spalding

Office Hours: CNS, room C006B
Mon/Fri: 2:00-3:50PM
Thurs: 4:00-4:50PM

556-3004

gspaldin@iwu.edu

Course Description:

-Whereas Optics in PHYS 106 considered only a few "sample rays," more powerful treatments consider the superposition of "many paths", and you want that kind of power! Our primary text, entitled Optics f2f: from Fourier to Fresnel, notes that "the essential insight of Fresnel was that all light propagation is [an interference phenomenon]." Fresnel's methods involve summing curved wavefronts emanating from each source point (and Fraunhofer's methods are simpler cases of Fresnel's). On the other hand, Fourier Optics involves summing plane waves. For all forms of interference (and hence all optical phenomena), phase differences between the contributing waves play a defining role, and so phasor diagrams will be stressed throughout.

- This course emphasizes hands-on instructional laboratory engagement supported by classroom discussion of mathematical modeling and the useful range of validity of various approximations. Labs begin with qualitative observation of polarization, followed by reminders of single-slit diffraction and multi-beam interference that were encountered in earlier coursework - but now put to use to find the "filling fraction" of various Digital Optics devices. These examinations extend to inexpensive Digital Micromirror Devices (DMDs), to transmissive "Spatial Light Modulators" (SLMs) taken from classroom projectors, and (very quickly) onwards to (much more useful) reflective SLMs such as the LCoS chip shown above. Because these LCoS devices allow simple programmatic control of phase and/or amplitude (or polarization) within many local regions across the field of a beam of light, they serve as tools for direct exploration of the mathematical models contained in the text, while avoiding the excessive burdens associated with manual alignment and re-alignment (and re-alignment and...) that would be required for systematic studies based on traditional (fixed) optical components.

- Students engage in qualitative observation of aberrations, using hand-held lenses, then "walking a laser" through "cloned apertures" on an optical breadboard, use shear-plate interferometers to test collimation, and build "optical cloaking devices" as a means of teaching ABCD matrices. Again, SLMs allow direct control of amplitude and phase modulation of beams, which is useful for teaching Fresnel Diffraction, Fraunhofer Diffraction, and Fourier Optics, as well as spatial filtering, computer-generated Holograms, Aberration Correction, Laser Modes, and much, much more (e.g., encoding information, the linear momentum, spin angular momentum, and orbital angular momentum of light beams). As time and student interest allows, structured investigations should lead to exploratory conversations, and onwards to independent projects, such as the design and construction of holographic optical trapping systems, or open-source "DIY" advanced imaging systems for use in local research projects. Each station has a 6.5-digit multimeter, a fiber-coupled photometer, a high-speed oscilloscope, a lock-in amplifier, and an RF supply for acousto-optic elements (for chopping or deflecting a beam), as well as stepper-motor-based motion control.

- Prerequisites: students are expected to have completed an university-level introductory sequence in physics (e.g., PHYS 101-102 or 105-106) providing a basic introduction to geometric ("ray") optics, as well as coursework in the "Mathematical Methods in the Physical Sciences" (e.g., PHYS 304, which uses the text by Mary Boas) providing facility with matrix multiplication, the mathematics of complex numbers, vector operators (divergence, gradient, curl, and all that), and some introduction to Fourier transforms.

This course complements "Scientific Imaging" (PHYS 308), as well as "Quantum Optics: the Momentum of the Photon" (PHYS 317), a new course that provides further introduction to single-photon quantum mechanics.

Reading material:

Perusing Sources that describe cutting-edge projects for your (electronically maintained) "Articles of Interest Log" is a key part of the course. You are required to add four new articles of interest each week, at minimum, to your log. This exercise becomes much more powerful when conversationally shared with others, and so such conversations are also required (and enter into your course grade!) You are encouraged to post notes on (or links to) projects of interest to any of our local student clubs:

Prepare For Each Lab:

There will only be two and a half hours of regularly scheduled lab time per week, but your activities must extend beyond this class time in order to achieve a desirable outcome.

Seek understanding of the appropriate reading materials before coming to lab!

Your laboratory notebook (maintained electronically or in handwritten form) should contain thorough sections covering each of the following areas, most of which require time outside of the regularly scheduled meetings (i.e., consider these tasks to be your homework for the laboratory portion of the course):

  • You are responsible for your experimental plan, and for connecting each element of your lab work to the underlying physics. You may cite sources, as long as you do so clearly and explain what you are learning from them.
  • Before taking data, engage in significant exploration of your experimental system. You should carefully note subtle changes from week to week, and should consider the physics underlying each element. Always consider the limitations of your equipment before beginning, to ensure that these limits are incorporated into your plan. All of these efforts should be clearly recorded in your laboratory notebook.
  • Clear predictive calculations serve as an important part of your experimental plan! Without them, you can neither celebrate having made correct predictions or having been surprised by nature! As you know by now, opportunities to celebrate should not be given up lightly.
  • Don't stop thinking about your work when the regularly scheduled meeting times draw to a close! A fair bit of "homework" will be needed in order for you to achieve the outcomes and level of analysis that you desire.

      - Lab Notebooks, whether maintained electronically or in handwritten form, must be accessible by the instructor and TA, for examination. Your lab notebooks are graded each weekend and are officially due every Saturday morning, by 9 am. Unexcused failure to work on your lab projects during a given week, results in a significant penalty.

      In grading your lab notebooks, I am looking for evidence of thought and analysis - and the degree to which you pursue clarity.

      - Let it be clear: the course is called "Optical Physics," and not "Optical Engineering." The end goal here is not a product; instead, you are expected to maintain a focus on trying to understand the underlying principles (which will serve you well even if you go into engineering).

Grading notes:

Final course grades will very heavily weight your laboratory performance.

Written work in lab notebooks will be assessed according to whether or not it compellingly presents clear attempts at application of physical and experimental principles. That is, you are to engage in argumentative writing (attempting, at each level, to present a cogent argument).

Writing aimed at (working towards or) conveying understanding is key!

Schedule undergoing REVISION:

-- What you see below constitutes random mutterings, and not (yet) a work of art:

Week

Readings to expect random quizzes on

Hands-on Grapplings

 Pen & Paper Exercises Computer Exercises Links
1
Pre-Term Prep Read Sect. 2.1-2.4 from our PHYS 317 text,
Quantum Mechanics: theory & experiment,
by Mark Beck, on the
"Classical Description of Polarization"
(also available in the library and the lab).

Also read Peatross & Ware Sect. 6.1 - 6.6

Printable Reference Sheet for the QUIZ:
Table of Jones Matrices
Aug 27 Class Consult your Intro Physics text re:
Dipole Antenna driven by an oscillator
Half-WaveAntenna
Sketch the E-Field along the Optic Axis, and think about polarization
...and propagation delays, or time lags.
Be prepared to discuss
your readings on Polarization
(By 9AM, post questions to Piazza!)
Aug 27 Lab Pre-lab readings:
Optics Rules to Live By!
and
Lab0 – Polarization
The SLM is
not like an absorbing polarizer;
it is like a transparent waveplate!

Optional supplement:
Birefringent Waveplates
Aug 29 Class Before class, read
Intro to Digital Optics:
with a Jones Matrix description of
(Polarizer + LCoS SLM + Analyzer)

Be prepared to utilize your readings.

Optional supplements:
Polarization Ellipse & Poincaré Sphere
Hurry to lab, for a QUIZ on implementing Ashley Carter's
"Optics Rules to Live By!"
Review notes on
in-class
hands-on demos:
Rope Wave and
Microwave Polarization
with discussion of
resistive losses
Lab0
Polarization:
Visible light polarizers,
Birefringent Waveplates: prequel to
Discussion of liquid crystals
You might also expect in-lab
hands-on demos:
Secret Monitors,
3D Glasses 		Pen&Paper HW #1 due
Sept. 3:
Exercises 1, 2, 4
from Ch 6 of
Peatross & Ware


Pen&Paper HW #2 due, start of class Sept. 5:
Exercises 5, 6, and 10, 11
from Ch 6 of
Peatross & Ware

Plan your next steps, and
schedule your time commitment
for a productive week
PositiveFeedback
When does a
Philosophy Student
become a Philosopher?
(Join the conversation
at the RSO Fair!) 		Read Programming in IDL
Sample code written in IDL is
so readable that it constitutes good
pseudo-code for those of you
who prefer a different language.
On a computer with a 2nd monitor,
set to 1920x1080 resolution,
I begin with two lines of code:
WINDOW, xsize=1920, ysize=1080
TV, MAKE_ARRAY(1920, 1080, /byte, VALUE = 128)
These create a window and then displays an image
with a uniform 128B "grayscale level."
You can systematically
vary this "grayscale level,"
to control the retardance
of an optical device.
Lab HW#1
due 1PM Sat
Processing/
Analysis
applied to your own data
from Lab0 		Here's a classic note by Jearl Walker, about how to make your own birefringent waveplates.
QuarterWaveplate
[Or, if you prefer, here's a searchable text version
of the same article.]

2
Pre-Week Prep Review
your
Intro-Level Physics
readings on
Single-Slit Diffraction,
and
Multi-Slit Interference

(You'll need the review!!)
Sept 3 Class Emerging opportunities in
Computational Optics
& further discussion of
"The Paradigm of Programmable Parts"

Be prepared to utilize
your review of Intro-Level Physics
readings on
Single-Slit Diffraction,
and
Multi-Slit Interference
Sept 3 Lab
Pre-lab reading:

Pixels as a Platform
Sept 5 Class In class, discuss your
finalized lab work and analysis,
and the Laboratory Optics text
Lab1
Pixels: "Diffraction Noise"
&
Filling Fraction
of various devices 		Pen&Paper HW #2 due, start of class Sept. 5:
Exercises 5, 6, and 10, 11
from Ch 6 of
Peatross & Ware


Pen&Paper HW #3 due
Sept 10:
Optics f2f Ch 1:
Exercises # 1.2, 1.6 		Due by 1PM Sept 7:

Processing/
Analysis
applied to your own data
from Lab1: Pixels


As a step beyond coding arrays with uniform grayscale level, you should now understand these four lines of IDL code:

GSL = 128
image = BYTARR(xpix, ypix)
halfpix = ypix/2
image[*, 0:halfpix] = GSL
 Embrace who we are:

3
Pre-Week Prep Shear-Plate Collimation Testers
(These will be used in Lab this week,
and will reappear in a homework shortly thereafter.)

Optional Supplement:
Shearing Interferometers
Sept 10 Class Read Sect. 0.1 - 0.2 of Peatross & Ware,
then read Ch 1 of Optics f2f,
recasting PHYS 106 in terms of
differentials (div, grad, curl, & all that),
connecting Optics to PHYS 406 E&M.
Highlight Phasors, Spatial Frequency.
*_IF reading is done, class meets in lab!_*
Sept 10 Lab Pre-lab readings:

Read this week's Lab Procedural noting that, to minimize aberrations,
the optic axis of each lens can be
aligned with the grid
of the optical breadboard, as a fiducial reference
(i.e., a "guide to the eye").
Key methods involve "walking" a laser through
"cloned" apertures,
and beam expansion & collimation.
Having mastered these, you can
apply your methods towards calibrating the retardance of
a programmable waveplate.
(Next week we encode local time lags)
Sept 12 Class Prepare to discuss Optics f2f Sect 1.12-1.15
and
Ray Tracing
*_IF reading is done, class meets in lab!_*
Lab2
Calibration:
Part A:
Alignment
"Walking" a laser through "cloned" apertures,
Beam expansion
&
Tests of collimation

Part A':
Aberrations
Qualitative observation, using
hand-held lenses, + Discussion


Part A'':
Amplitude Modulation
Programmatic control of a beam
 Pen&Paper HW #3 due
Sept 10:
Optics f2f Ch 1:
Exercises # 1.2, 1.6


Pen&Paper HW #4 due
Sept 12:
Optics f2f Ch 1:
Exercises # 1.10, 1.13, 1.14, 1.15


Pen&Paper HW #5 due
Sept 17:
Optics f2f Ch 2:
Exercise # 2.1
(A multi-part problem) 		Review my IDL code: pistonbatch.pro,
which creates sets of arrays
with different grayscale levels



Coding HW#3
due by NOON,
Sept 14:

Processing/
Analysis
applied to your own data
from Lab2:
If your output analyzer minimized transmission at GSL=0,
then at the GSL where transmission has maximally changed,
the SLM is acting as a HALF-WAVE plate (meaning it has added a phase change of π),
but at that point your fit function's argument has only changed by π/2.
That is, the
added phase shift
per GSL
is twice the value of B. 		This week in Lab:

Explore how lens misalignments
(e.g., tilt?, displacement from optic axis?, misplacement along optic axis?, etc.)
yield distinct types of Aberrations in a beam expander or telescope.

Be prepared to use the terms below to describe, on a QUIZ, these kinds of observations:

AberrationRays

Ray tracing credit: W M (Steve) Lee, now at The Australian National University

4
Pre-Week Prep
Fermat's Principle
and
Feynman's Phasors
Sept 17 Class Waive your geek flag high!
Wear a Nerd Shirt!!

Read Optics f2f Ch 2 :
Compare p. 5 phasors to p. 19 propagator

Pay special attention to
Exercises 2.5 and 2.6, re:
Sculpting output via
simple phase delay optics:
Case A: single-beam collimated input into a prism
yielding plane waves with
redirected k-vector
(imposing a linear phase lag)

Case B: single-beam collimated input into a plano-parabolic lens
yielding curved wavefronts moving towards the focal point
(imposing a quadratic phase lag)

Sect. 2.13 onward,
"Paraxial" Optics
Sept 17 Lab Pre-lab readings:

Last week, you encoded spatial patterns
into a beam.
For this week's lab, read about
Phase-Modulation Mode
and
Consideration of time lags
encoded into local regions of a beam

Note the subtle changes in the set-up,
and consider the reasons!
(Michelson Interferometers will be
treated in detail in Optics f2f Ch 3 HW)
Sept 19 Class Wear a Nerd Shirt!!

Prepare to discuss Optics f2f Ch 2 ,
to the end!
Lab2
Phasing Fringes:

Towards computer-controlled holograms:

Phase-only Modulation


You depend, critically, on keeping
EVERY
LITTLE
THING
organized! 		Pen&Paper HW #5 due
Sept 17:
Optics f2f Ch 2:
Exercise # 2.1
(A multi-part problem)


Pen&Paper HW #6 due
Sept 19:
Optics f2f Ch 2:
Exercises # 2.4, 2.5, 2.6


Pen&Paper HW #7 due
Sept 24:
Optics f2f Ch 2:
Exercises # 2.7, 2.8, 2.9 		Sometimes your method for
calculating an array might
yield a non-BYTE data type.
For example, "blaze.pro" is
my code for creating a "phase
profile" that is linear in
some cartesian direction, ...
but because I often ADD these
phase profiles on top of other
calculated phase profiles,
to avoid rounding errors,
blaze returns a "floating point array."
To be recognized as a valid image,
use:

image = BYTE(image)
or
image = BYTSCL(image)

Details are available online


Coding HW#4
due by 2:30pm, Sunday:

Analysis of your own data
from this week's
LAB 		Imposing simple phase profiles can create and redirect multiple focal spots
(which, if aberration is minimal, can act as Optical Traps,
for micromanipulation of micro- and nano-components, or cold atoms)

TimeLagIsPhaseLag

A prism imposes local time delays equivalent to a linear phase lag


Similarly, a lens is equivalent to a parabolic phase profile.
For continuous wave illumination, we can write these phase profiles
modulo 2π:
ThatsAllFolks

Simple phase profiles can be added (modulo 2π) to place multiple foci in three dimensions.
Note, too, that we can use such profiles to remove aberrations
of the sorts you explored last week
(e.g., due to displacement from optic axis, displacement along optic axis, etc.)

5
Pre-Week Prep
Review Diffractive Orders
and
Read Optics f2f Ch 3:
Multi-beam interference
Sept 24 Class
Read up through Optics f2f Sect 3.7
Multi-beam interference

(Note phasors carefully)

(In lab, you've seen
the Fizeau Wedge
– as a shear-plate collimator –
and the Michelson Interferometer
– used in Lab 2)
Sept 24 Lab
Key Pre-lab readings:

Review the written solutions to
Exercises 2.5 and 2.6

Read
Experiment IV: Wave Shaping

We start with
Diffractive Optic Elements (DOE)
that are equivalent to
Prisms & Lenses,

...which can be combined
modulo 2π,
as an initial means
to sculpt patterns in 3D

(some coding required)

Sept 25 "The Wesleyan Titan" first appeared Sept. 25, 1965
Here's IDL code for you to create a
Computer-generated Hologram (CgH)
of Tommy Titan
Sept 26 Class
Discuss upcoming exam
Coverage: through Optics f2f Sect 3.7
and earlier readings

(Including labs up through Lab 4)
Lab4
Wave Shaping:


You will create
plane waves,
and
curved wavefronts
that travel along different directions by imposing simple
phase profiles


(and explore aliasing)


&
Computer-generated Holograms
Version 1.0
(Discuss Non-iterative Diffractive Optic Elements vs. Iterative CgH algorithms) 		Pen&Paper HW #7 due
Sept 24:
Optics f2f Ch 2:
Exercises # 2.7, 2.8, 2.9


Pen&Paper HW #8 due
Sept 26:
Optics f2f Ch 3:
Exercises # 3.1, 3.2, 3.4 		Coding HW#5
due by 2:30pm, Sunday:

Program your own phase profiles:
begin by considering basic symmetries,
each of which yields a distinct set
of BASIS states:

A linear phase gradient, in cylindrical
coordinates, along the radial direction
yields a Bessel beam
("drum head" modes that form, e.g.,
a basis set for all 2D wave physics
with cylindrical symmetry).

A linear phase gradient,
in cylindrical coordinates,
along the azimuthal direction
yields Orbital Angular Momentum,
in beams called
"Laguerre-Gauss" modes.

Adding OAM and Bessel
phase profiles yields
"Higher-Order Bessel Beams" (HOBBs).
Learning about such beams
can unify much
of what you've learned in other courses.

A linear phase gradient
along a cartesian direction
(or superposition thereof)
yields a plane wave deflected to some
ANGLE
(the basis of "Fourier Optics").

A quadratic phase gradient yields a SPHERICAL wave
(the basis for Huygens-Fresnel Optics).

What might a cubic phase gradient yield?
 You are invited to take over the development of this app:
iHologram renders Fraunhofer holograms
that can be used, e.g., for Holographic Optical Tweezers and for Computational Ghost Imaging iHologramInstructions
Richard Bowman originated this app while in the Optics Group at Univ. of Glasgow

6
Pre-Week Prep Review for Exam!
Oct 1 Class

EXAM #1: up through Optics f2f Sect. 3.7, and
up through Lab 4


Oct 1 Lab Key Pre-lab reading:

Experiment V:
This time, take the initiative to be a bit more systematic in your data taking and subsequent analysis
Virtual Slits:
measuring diffraction & interference
in the absence of any real diffractive object

Note that the use of virtual apertures
eliminates
the need to do lots of manual realignment
each time we change the diffraction objects!!!
Oct 3 Class
Two interfering beams cannot cancel
at any point
unless they share the same polarization,
...but what about three beams?

Read Optics f2f Ch 4 in its entirety:
Polarization (Redux)

In-class bling contest:
How could your set-up use a Polarizing Beam-Splitter cube
(PBS, Sect. 4.10)?
How about a wave plate (Sect. 4.13)?
Can you explain our
polarization-directed flat lens?
Lab V :

Systematic Study of Aperture Functions
(Redux)

This time, take the initiative to be a bit more thorough in your data taking and subsequent analysis 		Pen&Paper HW #9 due Oct 3:
Optics f2f Ch 3:
Exercises # 3.5, 3.6, 3.11


Pen&Paper HW #10 due
Oct 8:
Optics f2f Ch 5:
Exercises # 5.2, 5.3, 5.4, 5.5 		Check out the
Code Book
for Optics f2f!



Coding HW#6
due by 2:30pm, Sunday:

Processing
and
Analysis
applied to your own data
from this week's
LAB

Would you call this
"Fringe Science"? 		Charles Adams describes this simulation
superimposing two co-propagating waves of opposite handedness
(Adjusting their relative phase difference will rotate the Polarization of the resultant wave):

Visualizations can help you to think about polarization!

7
Pre-Week Prep Read Optics f2f Sect. 5.1-5.6:

Fresnel

Key, beneath Eqn 5.3:
"This equation says that ...the Fresnel diffraction integral
extends the discrete phasor sum we encountered in Ch 3
to infinitely many waves."
Oct 8 Class
"Fraunhofer used a simplified form
of Fresnel's wave theory"
Read Optics f2f Sect. 5.7-5.8:
1D Fraunhofer diffraction
Oct 8 Lab Key Pre-lab readings:

Read Experiment VI:
Visualizing Shaped Wavefronts
via Michelson Interferometry
(Review Optics f2f Sect. 3.12,
and Exercise 3.11)

LIGO analogy lab
Oct 10 Class Read Optics f2f Ch 5 remainder
2D Fraunhofer diffraction, etc.
Lab VI:

Michelson Interferometer

&

Discussion of LIGO

&

Interference between a Reference Beam and a Shaped Wavefront
(Redux)

This time, take the initiative to be a bit more systematic in your data taking and subsequent analysis 		Pen&Paper HW #10 due
Oct 8:
Optics f2f Ch 5:
Exercises # 5.2, 5.3, 5.4, 5.5


Pen&Paper HW #11 due
Oct 10:
Optics f2f Ch 5:
Exercises # 5.7, 5.8, 5.9


Pen&Paper HW #12 due
Oct 15:
Optics f2f Ch 5:
Exercises # 5.13, 5.14, 5.15 		Check out the
Code Book
for Optics f2f!



Coding HW#7
due by 2:30pm, Sunday:

Processing
and
Analysis
applied to your own data
from this week's
LAB

Explore the effects of the radius of a circular aperture in this simulation from Optics f2f, showing both
a transverse slice (i.e., the imaging screen view), as well as,
a longitudinal slice (i.e., tracing out the beam propagation):

Charles Adams provides a quick overview/perspective in his blog

8
Pre-Week Prep
In preparation for the next EXAM, consult Peatross & Ware:

P&W Ch 10, "Diffraction,"
(Read the Exercises, too)
(Watch video in L10.2)

P&W Ch 11 gives examples
(Exercises also have videos)
Oct 15 Class
Prepare to discuss
Optics f2f
Ch 5:
Fresnel & Fraunhofer
and
"Conjugate Planes"
and
Computer-generated Holograms (CgH)
Oct 15 Lab
Pre-lab readings:

Through the looking glass

((((((((())))))))))

Oct 17 Class
Fourier Optics begins!

Pore over Sect 0.4 of Peatross & Ware

For the return of
the propagator
("I'll be back!")
read
Optics f2f
Sect. 6.1-6.4
Holograms :

Functional Holographic (Magic Cube) Keyboard,

Diffractive Optic Elements,

Computer-Generated Holograms
Version 2.0
(Towards Iterative algorithms),

Holograms of Physical Objects
(LitiHolo Kits
&
the magic
of cut glass),

Chess (Up)Sets 		Pen&Paper HW #12 due
Oct 15:
Optics f2f Ch 5:
Exercises # 5.13, 5.14, 5.15


Pen&Paper HW #13 due
Oct 18:
Optics f2f Ch 6:
Exercises # 6.1, 6.2, 6.3, 6.4, 6.5


Pen&Paper HW #14 due
Oct 22:
Optics f2f Ch 6:
Exercises # 6.6, 6.7, 6.8, 6.9
(which simply asks you to write up Sect. 6.3-4, plugging in a few numbers for perspective). 		Check out the
Code Book
for Optics f2f!



Have you tried using IDL to calculate the hologram
of Tommy Titan yet?

 Explore online visualizations and the #PhysicsFactlet series
tweeted by Jacopo Bertolotti of the Univ. of Exeter, such as this one:
For all of his pedagogical visualizations, Prof. Bertolotti makes his Mathematica code available
on Wikimedia Commons

9
Pre-Week Prep
You should say
"Yea!" more, for more Fourier!

Read
Ch 7 in Peatross & Ware
Oct 22 Class
You should say
(read it aloud):
"Yea!" more, for more Fourier!


Read
Ch 7 in Peatross & Ware
Oct 22 Lab
Paradigm-establishing
Pre-lab readings on
"Pixels as Platform:"

Creating a
Virtual Instrument:

Read
Experiment VII:
Dispersion
studied using Digital Optics
to create a
virtual spectrometer
Oct 24 Class Prep for your in-class bling contest:
Read Optics f2f Appendix B:
Fourier Transform Toolkit
(Highlighted on inside back cover)
Lab VII:

Dispersion studied using Digital Optics to create a virtual spectrometer 		Pen&Paper HW #14 due
Oct 22:
Optics f2f Ch 6:
Exercises # 6.6, 6.7, 6.8, 6.9
(which simply asks you to write up Sect. 6.3-4, plugging in a few numbers for perspective).


Pen&Paper HW #15 due Oct 24:
Optics f2f Ch 6:
Exercises # 6.10, 6.11


Pen&Paper HW #16 due Oct 29:
Optics f2f
Ch 6:
Exercises # 6.18, 6.19, and
Appendix B:
Exercise B.3 		Check out the
Code Book
for Optics f2f!
 Dispersion (e.g., in a prism) and diffraction (as shown below in a figure from Optics f2f)
can both induce changes in the propagation direction of light.
Explain why, with dispersion higher frequencies are deflected most,
but for diffraction the higher frequencies see the least displacement.

10
Pre-Week Prep
Read Sect. 9.3 of Peatross & Ware, about
Matrix Methods for "Paraxial" Optics.
-- Expect a quiz! --
Oct 29 Class
Expect a quiz on
Sect. 9.3 of Peatross & Ware, about
Matrix Methods for "Paraxial" Optics
Oct 29 Lab
Pre-lab readings / viewings:
Read the work of Choi and Howell,
and view their (4) supplemental movies.
In lab, you will follow this work, using ABCD matrices
to design and build a "Cloaking Device," out of
whatever extra large-diameter lenses are at hand.
Oct 31 Class
EXAM #2: reading Ch 7 is likely to help to solidify your understanding of Fourier Transforms, though the test will be designed to cover only up through Optics f2f Sect. 6.4

Optical Cloaking:
a means of teaching
ABCD matrices




ABCD Matrix Tutorial 		Pen&Paper HW #17 due Oct 31:
Optics f2f Ch 7:
Exercises # 7.1, 7.7, 7.8


Pen&Paper HW #18 due Nov 5:
Optics f2f Ch 8:
Exercises # 8.1, 8.2, 8.3, 8.4 		Check out the
Code Book
for Optics f2f!



Coding HW#9
due by 2:30pm, Sunday:

Processing
and
Analysis
applied to your own data
from this week's
LAB

"Cloaking" device using ordinary lenses to hide objects across range of angles:

11
Pre-Week Prep
Read the remainder of Ch 7:
Time Domain

Plan your lab, identifying needed items for your INVENTED method!
Nov 5 Class A Treat! A Beam Shaping Tutorial!
and
Optics f2f thru Sect 7.3:
Windowing and Spectral Leakage

Read Optics f2f Sect. 8.1-8.3:
Temporal Coherence
Nov 5 Lab
Key Pre-lab material:
Image Processing without a computer:
Your task is to INVENT how to improve upon this, with Programmable Optics
Nov 7 Class
Read Optics f2f Ch 8 remainder:
(noting Power spectral density)
&
This short blurb examining
Young's Double Slit in Color,
by Charles Adams
Lab VIII:

Image Processing at the speed of light

INVENT your own procedure before coming to lab!

As you build multiple copies of conjugate planes, you naturally end up with lenses separated by the sum of their focal lengths ("beam expanders/reducers")

Ask, in advance,
for any needed items
(e.g., a shear-plate collimator may be useful)
Take steps TOWARDS your lab practical exam! 		Pen&Paper HW #19 due Nov 7:
Optics f2f Ch 8:
Exercises # 8.5, 8.6, 8.7


Pen&Paper HW #20 due Nov 12:
Optics f2f Ch 9:
Exercises # 9.1, 9.2, 9.3, 9.4 		Check out the
Code Book
for Optics f2f!



Coding HW#10
due by 2:30pm, Sunday:

Processing
and
Analysis
applied to your own data
from this week's
LAB

As described in this short blurb by Charles Adams,
explore Temporal Coherence effects, using the slider at the bottom of this figure from Optics f2f:

12
Pre-Week Prep

Read Optics f2f Ch 9:
Point Spread Function, etc.

Plan your lab!
Nov 12 Class

Read Optics f2f Sect. 9.1-9.3:

Imaging

Zeiss,

Abbe,

PSF
Nov 12 Lab

Pre-lab readings:

Talbot Self-Imaging
(The topic of Experiment IX)

See Fig. 9.12: two lenses separated by the sum of their focal lengths acting on a "Ronchi Ruler," described in the section on "The Talbot Effect," p. 87-88

Optional supplement:
Observation of the Talbot effect
with water waves
Nov 14 Class
Read
Optics f2f Sect. 9.4-9.5
Lab IX:

Talbot Self-Imaging

Invent your own procedure before coming to lab!
Pen&Paper HW #20 due Nov 12:
Optics f2f Ch 9:
Exercises # 9.1, 9.2, 9.3, 9.4


Pen&Paper HW #21 due Nov 14:
Optics f2f Ch 9:
Exercises # 9.5, 9.6, 9.7 		Check out the
Code Book
for Optics f2f!



Coding HW#11
due by 2:30pm, Sunday:

Processing
and
Analysis
applied to your own data
from this week's
LAB

Scroll down within this pane for a celebratory discussion of Talbot Self-Imaging:
Greg Gbur, who writes the "Skulls in the Stars" blog, is a professor at UNC-Charlotte

13
Pre-Week Prep
Read
remainder of
Optics f2f Ch. 9
Nov 19 Class
Discuss
remainder of
Optics f2f Ch. 9
Nov 19 Lab
Pre-lab readings:

Experiment X:
Phase-Shifting
Digital
Holography

&

Computer-Generated Holograms
Version 3.0: Iterative algorithms
&
The Optimization Conundrum
(Simple metrics of efficiency can be misleading)
Nov 20 Event! STEM Career Fair
6:30-8:00PM
Young Main Lounge
Nov 21 Class
Read Optics f2f Ch 10.1-10.6:
Spatial Filtering examples
Lab X:

Phase-shifting Digital Holography

&

Computer-Generated Holograms
Version 3.0:
Iterative algorithms
&
The Optimization Conundrum 		Pen&Paper HW #22 due Nov 19:
Optics f2f Ch 10:
Exercises # 10.1, 10.2, 10.3


Summer Internship Applications

(A required, graded exercise)

 Check out the
Code Book
for Optics f2f!



Coding HW#12
due by 2:30pm, Sunday:

Processing
and
Analysis
applied to your own data
from this week's
LAB

14
Pre-Week Prep
Read Optics f2f Ch. 11
Beam Waist vs. Rayleigh Range,
& Gouy Phase, etc.
Nov 26 Class
Disucss Optics f2f Ch. 11
Beam Waist vs. Rayleigh Range,
& Gouy Phase, etc.

Note: EXAM #3 delayed to Dec. 3
Nov 26 Lab Our Lab for this week is online (only):

Analyze every single option available in
this Optical Tweezers simulation
(using strongly focused light):


Requires that you install
the latest version of Java,
and grant permissions to run
(Post questions to Piazza)
Nov 28 Class (No class today)
Enter your analysis of the
Optical Tweezers app
(at left)
into your lab notebook


Pipe up (!) if you wish to supplement the simulation
by constructing your own
(live, hands-on) version of
Optical Tweezers
or
Holographic Optical Traps 		Pen&Paper HW #23 due Nov 26:
Optics f2f Ch 10:
Exercises # 10.5, 10.7, 10.10 		Check out the
Code Book
for Optics f2f!



Coding HW#13
due by 2:30pm, Sunday:

Processing
and
Analysis
applied to your own data
from this week's
LAB

Sometimes, information carried by light appears to be lost:


If we are clever enough, there can be ways of recovering "lost" information:

15
Pre-Week Prep Review Piazza Note on
"Making Sense of
Equations"
Dec 3 Class EXAM
(originally scheduled for last Tuesday)
Dec 3 Lab Lab Practical: Spatial Filtering
Dec 5 Class Opportunities in
Computational Optics
&
The Paradigm of Programmable Parts
(Redux)


The Big Picture
Lab Practical:
Release Schrödinger's Cat!

Mull over the concept of
"Thing"-ness

Catch-up /
Wrap-up


Summer Internship Applications
(A required, graded exercise) 		Remember, all information is physical:

I'm interested in ways to recover
information that appears to be dissipated during transmission.

Wanna play?

16

 Final Exam:
Thursday, Dec. 12,
3:30-5:30PM
 Room E101
Center for Natural Sciences
** Class Discussion Page on Piazza **
Course Plan

...You might be interested in discussing articles we've produced on these topics:

Your Dungeon Master: Office Hours

Gabe Spalding
(wishing you grand adventure) 		(In CNS room C006B)
Monday: 2:00 - 3:50pm
Thursday: 2:30 - 4:20pm
Friday: 2:00 - 2:50pm

Grow the Conversation:

Our primary electronic form of communication is not email, but is via the Class Discussion Page on Piazza,
so please check the desktop version of that site regularly.
(There is also a free smartphone app for Piazza, and while it will display equations beautifully,
it is not as useful as the desktop version,
which provides a graphical template for entering LaTeX.)