The first couple of pages of this pdf are the most relevant. But it's recommended that you peruse the entire document and give special notice to the Laser Diode and Fiber Laser sections.
The pdf above referred to a unit of energy known as the electron-volt (eV) (Fig. 36.1) when talking about quantum energy levels of an atom. Due to the small scales of single electrons, atoms and photons, conventional units of energy (Joules) are far to large to be convenient. In comparison:
1 eV = 1.602 x 10^-19 Joules or 1 Joule = 6.242 x 10^+18 eV.
This link explains about the electron volt and how to calculate energy in electron-volts: Electron-volt Calculator.
And here's a short video showing the relationship between Joules and electron-volts: What Exactly Is an Electron-Volt? (2:22)
Here is Explainthatstuff.com on Fiberoptics.
Refractive Index of Materials and Total Internal Reflection (scroll down for the pics!
) from Wikipedia.Why Does Light Slow Down in Water? (10:23) YouTube presentation. Watch this video.
This video is posted just for your own interest. It's another presentation by the same person as the above video explaining Why you can't go faster than light. (8:36)
Here are several videos explaining the operation of lasers. These are relatively short and each uses different techniques to explain the theory behind laser operation. How Lasers Work - A Complete Guide (20:44), The Simple Physics of a Laser (12:36) and Introduction to Lasers [Year-1] (11:10).
For more detailed information on lasers & fiber-optics, you are encouraged to watch these MIT offerings:
Laser Fundamentals 1 (58min), Laser Fundamentals 2 (55min) and Laser Fundamentals 3 (54min). These are courses created by MIT so they are generally above a 2-year A.S. Degree level. Still, you might be able to get some decent information out of them. And if you're still awake after watching those, this is this video on Fiber-Optic Fundamentals (54min), also from MIT. Again, these are fairly detailed and are provided more as FYI content than required course content.
This video is a pretty complete discussion of fiber-optics. It is 2 hr. and 10 min. long. You are encouraged to watch it as an FYI for most of it. Free 2 Hour Fiber Optic Training (2:10:41)
To give you some idea of the content there is an interactive index listed in the description of the video. It looks like this:
- 0:00 - Introduction from John Bruno
2:35 - Chapter 1: Fiber Optic Theory
16:59 - Chapter 2: Fiber Optic Connectors
21:55 - Chapter 3: Splice On Connectors
37:52 - Chapter 4: MTP/MPO Style Connectors
46:43 - Chapter 5: Fiber Optic Cable
53:45 - Chapter 6: Fusion Splicing
1:06:12 - Chapter 7: Cleaving Fiber
1:14:57 - Chapter 8: OTDR Operation
1:24:43 - Chapter 9: Power Meter & Light Source
1:28:45 - Chapter 10: MTP/MPO Test Set
1:34:23 - Chapter 11: Enclosures
1:40:33 - Chapter 12: Network Design
1:49:43 - Chapter 13: Cleaning Fiber
1:59:15 - Chapter 14: FIS/Conclusion
This video on Network Connectors (9:42) reviews the common connectors used on networks including wired & fiber-optic cabling. Not a lot of theory in this presentation, but it nicely ties together applications of some theories we've discussed this semester such as Unshielded Twisted Pair, Shielded Twisted Pair, Co-Axial cables and Fiber-Optic cables. You have probably seen and used several of the cables presented. It's a good presentation of various connectors commonly used in network topologies of various types.
Here's a pdf of a Laser Safety Training Guide that begins with a good introduction to lasers and then describes the various aspects of safety procedures, protocols and equipment needed in an environment that uses lasers.
Vacuum Systems
Before we get into the details of vacuum systems, here are a few review topics from EET-120 Fluid Power Technology. Definition of 1 bar of pressure from Wikipedia. And here's a refresher on Gauge Pressure and Absolute Pressure Measurement and this graphic which shows the relationship between them.
- Absolute & Gauge Pressure Graph.jpeg (34.97 KiB) Viewed 531 times
I introduce this website in the EET-120 Fluid Power Technology class, but I'll repeat it here as it can be quite handy when dealing with various units, and the units commonly used in pressure and vacuum systems are fairly numerous. So if ever needed, click on this Online Conversion - Convert Just About Anything to Anything.
Fundamentals of Vacuum Theory - Part 1 from Vacaero.com. Be sure to read the paragraph above the picture of the grand canyon. It's a staggering presentation of what is required to achieve what is called "ultra-high vacuum" in modern systems.
Electron Beam Welding from Wikipedia.
Here's a good read comparing Electron Beam and Laser Beam Welding from The Fabricator.
And this one: Electron Beam vs.Laser Beam Welding.
And this short video Differences Between Electron Beam Welding and Laser Beam Welding (2:58)
Conventional & Laser CNC Machine by Merubeni Citizen-Cincom.
Universal Laser Systems - How Digital Laser Material Processing Works (2:44)
And for additional information, it's not just electrons and photons which can have all of the fun in machining. Water jets can make impressive cutting tools.
What is Waterjet Cutting Technology?
And here's a video showing some water jets in action Waterjet Cutters (3:06)
Some local companies you may have heard of which make use of or produce laser and/or electron-beam equipment. Representatives from each of these companies have attended recent Project Presentations/Advisory Board Meetings. I believe each of them is currently looking for technicians.
Meribeni Citizen-Cincom in Agawam, MA.
Joining Technologies in East Granby, CT.
PTR - Precision Technologies in Enfield, CT.
Trumpf in Farmington, CT.