Richard Gnall

Photonics 230 – Laser Electronics

Electromagnetism | Radiometry | Vision | Semiconductors | LED | LD | Detectors | Fibers | Circuits

Photonics 230 is a survey course covering a wide range of topics including electro-magnetic theory, radiometry, human vision, laser theory, semiconductor light sources and detectors, and circuit design. As there is no textbook for much of the course material, this web page provides a collection of online references to supplement the lectures.

Electricity and Magnetism 
Electric field of a point charge
Electric field of a point charge. From the Georgia State University HyperPhysics project.
Electric Field Applet - Caltech
"This applet allows the user to set up a distribution of charges, upon which the applet will show the electric potential, electric field lines, and equipotential lines. In addition, the electric force will be observed through real time interaction of charges."
Electric Field and Potential Lines Applet
"Field lines are an abstract concept (in that they don't really exist and can be difficult to visualize). We recommend that you use this applet to get a feel for electric field lines and electric potential lines for a number of different point charges with different magnitudes, signs, and values."
Dielectric Polarization
Schematic discussion of polarized dielectrics between capacitor plates.
Electromagnetic Theory - Maxwell's Equations
Summary of Maxwell's Equations from the lecture notes for Physics 4323 - Optics at Texas A&M University.
Radiometry and Photometry 
Inverse Square Law and Lambertian Surfaces
Discusses the Inverse Square Law for point sources and the uniform radiance of Lambertian surfaces. From the Light Measurement Handbook by Alex Ryer of International Light, Inc.
Light Measurement Handbook
Hard copy and .pdf versions of a handbook covering radiometry and photometry. Created by Alex Ryer of International Light, Inc.
Radiometry and Photometry FAQ
This HTML/.pdf FAQ addresses the "misinformation and conceptual confusion regarding photometry and radiometry". The .pdf version contains more information. By Emeritus Professor James M. Palmer of the Optical Sciences Center at the University of Arizona.
Photometry (.ppt)
Review of basic radiometric quantities. Powerpoint presentation with clear diagrams and definitions by robotics and computer vision Professor Frank Dellaert and computing Professor Jim Rehg, both of GeorgiaTech.
Radiometry and Rendering Equation (.pdf 497KB)
Mathematical treatment of radiance. From CS 665 Advanced Interactive Rendering, a computer graphics course at Cornell University by Professor Kavita Bala.
Introduction to Illumination
A good schematic explanation of the how radiance depends on the projected area and not just the intercepted area. By Professor James Stewart of Queen's University Computing Department.
Radiometry and Photometry
From the University of Tennessee.
Human Vision 
3-D Color Space
CIE color chart and various RGB color cube illustrations. (Scroll down.)
Color Spectrum Charts
Under "Items of Interest", in part I of Sam's Laser FAQ, there is a series of beautiful color spectrum charts.
Rods and Cones
Good color spectrum charts and description of the differing roles of rods and cones. (Scroll down.)
Spectral Sensitivity Curves of Rods & Cones
Results based on microspectrophotometry.
Vision Curves
Luminous efficacy graphs for photopic and scotopic vision, and a perceived brightness graph of diffusely reflected light.
Light and the Eye
A lengthy treatise on the biological basis of color vision by Bruce MacEvoy. (His complete website is fascinating.)
Color Vision
A lengthy treatise on color by Bruce MacEvoy. (His complete website is fascinating.)
Semiconductors 
Periodic Table
Interactive periodic table from WebElements.
Conductors, Insulators and Semiconductors
From the Department of Materials Science and Engineering at the University of Illinois Urbana-Champaign for the Materials Science and Technology Teacher's Workshop (MAST).
Semiconductor Wikipedia Entry
Wikipedia, the free, copyleft online encyclopedia, has links to information on valence bands, band gaps, and other semiconductor principles.
Semiconductor Reference
From HyperPhysics.
Britney's Guide to Semiconductor Physics
From Carl Hepburn at The University of Essex. Semiconductor basics along with information on lasers, photonic crystals, and photolithography. (This listing is by no means an endorsement of Ms. Spears.)
Crystalline Properties of Semiconductors
Crystal structure, lattice parameters, density, and bulk modulus of elemental and binary semiconductor compounds.
Physical Properties of Semiconductors
Band structure and carrier concentration. Electrical, optical, thermal and mechanical properties of major semiconductors and semiconductor compounds.
Properties of the III-V Compound Semiconductors
A listing of physical properties for nine different kinds of III-V semiconductor materials.
Light Emitting Diodes 
How Light Emitting Diodes Work
From How Stuff Works.
The Radiometry of Light Emitting Diodes (.pdf 436KB)
From Labsphere.
Laser Diodes 
The Diode Laser – The First Thirty Days Forty Years Ago
History of the 1962 invention of the laser diode. By Russell Dupuis of Georgia Tech.
Diode Lasers - An Overview
From Oxford University, 1994.
PHTN 1531 – Opto-electronic Devices
This course from Niagra College contains many outstanding powerpoint presentations on the fundamentals of light, semiconductors, laser diodes, and LEDs.
Luxpop Index of Refraction Values and Photonics Calculations
Online resource for calculating a large of optical properties, including index of refraction, reflectivities, free spectral range, gaussian beam propagation, polarization system analysis, wavelength conversions, dB/percentage conversion, optical computing, gaussian curve fitting, and cytometry.
Detectors 
Newport Corporation Tutorials
Photonics tutorials on the testing and characterization of laser diodes. From Newport Corporation.
Antireflective Coatings for Optical Storage Devices
Tutorial on different types of antireflection coatings for silicon sensors used in CD, DVD and Blu-ray optical storage systems. From SPIE oemagazine.
Photovoltaic Technology
Very basic tutorial on photovoltaic power cells from the U.S. Department of Energy.
Fibers 
Fundamentals of Fiber Optics
"An Introduction for Beginners" by Volpi Manufacturing, 2000.
Pulse Spreading Through a Dispersive Material
Animated GIF demo of pulse spreading in a fiber. Other Interactive Animations of Fiber Optic Phenomena are available.
Fiber Optic Communications
Course S-72.227 Digital Communication Systems from The International Master's Program in Telecommunications at the Helsinki University of Technology.
Photonic Crystals: Periodic Surprises in Electromagnetism
A five-part series of lectures on photonic bandgap materials and fibers. This tutorial from MIT provides a wealth of information about the physics and engineering of periodic optical solids. Lecture 5 contains a link to a movie of a "hollow bandgap polymer/chalcogenide fiber carrying 1-2W of 10.6um laser power, burning a hole through a post-it note covered with a film of the same polymer". Requires substantial knowledge of math, electromagnetism and solid state physics.
Circuit Design 
Designing Photodiode Amplifier Circuits With OPA128 (.pdf 77KB)
Various TIA transimpedance amplifier designs using an OPA128 op-amp. Application note from Burr-Brown.
Circuit Diagrams for Commercial Lasers
Parts III and IV of Sam's Laser FAQ contain many circuit designs for commercial and home built laser power systems. This web page also contains many photos of individual laser parts, schematic diagrams of laser systems, and laser safety warning signs.