Business
Lasers
Optics

Curse of Knowledge

By Greg Ingersoll | Posted December 17th, 2009 at 09:54

It’s been a while since I posted anything, and there’s a good reason for it: Quantum mechanics. My last post was in a series of three (or more) covering the dissection of a He-Ne laser that is still sitting on my desk at work. That post covered the power supply which is relatively straightforward to discuss even if the reader isn’t an electrical engineer. Ok, well, at least I could show pictures of the dusty old guts of a laser built thirty-plus years ago.

The next post in the series needs to deal with optical gain. And optical gain is based on photon absorption and emission which is in turn based on quantum energy levels in atoms. This isn’t a topic that lends itself to annotated photographs, and it tends to be almost exclusively mathematical in nature. Thinking about how to briefly cover the fundamentals of gain in a laser got me thinking about something else: the so-called Curse of Knowledge. Read the rest of this entry »

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Electrical Engineering
Lasers

More. More Power.

By Greg Ingersoll | Posted November 22nd, 2009 at 15:34

This is the second post in my dismantling-a-borderline-antique-Helium-Neon-laser series. In the first post, the project was introduced, and it was mentioned that every laser has three primary components: a power source, gain, and feedback. This post discusses the power source for this laser.

You can put energy into a laser system in many different ways, and the preferred method typically depends on the gain medium in use (which will be discussed in a later post). These methods include flash lamps, electric current through a diode, other lasers, chemical reactions, and electric current through a discharge tube. The last in the list is what is used in a HeNe laser and other similar lasers that use a gas-mixture as the gain medium.

Side view under the hood. The glowing laser tube is obvious. In front of that is the main circuit board. To the right of that is the transformer. And at the far right is the power switch. In the back of the frame is the mains power cord connected to the wall.

Side view under the hood. The glowing laser tube is obvious. In front of that is the main circuit board. To the right of that is the transformer. And at the far right is the power switch. In the back of the frame is the mains power cord connected to the wall.

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Lasers
Optics
Physics

Three Ingredients

By Greg Ingersoll | Posted November 13th, 2009 at 15:55

As I write this, I’m sitting in the offices of Hashrocket in Jacksonville, Fl, looking at the ocean and balancing a cappuccino on my laptop. It actually makes it difficult to type, but I digress. This post has nothing to do with Florida or the ocean or cappuccino; I’m just boasting.

This post is the first in a series that covers something that has been in the front of my mind for several years now: lasers. I’ll pause a moment for you to get all of the movie references/jokes about sharks out of your system.

…

Ok. Lasers are used all over the place: medicine, communications, measurement, meteorology, astronomy, data storage, pointing. The list goes on. But, to paraphrase Jerry Hathaway in Real Genius (watch it right now), “the [laser]. What does it look like?”

Lasers come in many forms, but all have three common ingredients: a power source, gain, and feedback. Each of these will be covered in future posts in more detail. This post is just here to introduce the specimen of study.

My friend and colleague, Mike, had this beauty collecting some dust at his desk.

1980 Gammex He-Ne Laser

1980 Gammex He-Ne Laser

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Cocktails and Drinks

Not One in Twenty

By Greg Ingersoll | Posted October 25th, 2009 at 14:32

I’ve been reading the book Imbibe! by David Wondrich who I first saw several months back on The Colbert Report. The idea behind the book is that it is a historical and very detailed guide to classic American mixology. The book includes anecdotes and recipes dating back to the mid-1800s or so, through the early 20th century, and presumably beyond (I haven’t finished reading it yet). It invokes images of what must have been a much better time for the social cocktail drinker than now. (That’s cocktail in the lowercase, generic sense; Cocktail refers to a particular drink popular after the Civil War consisting simply of spirits, gum syrup, bitters, and curaçao. [1])

Don’t get me wrong. There are still a lot of good bartenders out there, but many of them, through no fault of their own, must serve drinks made with various pre-mixed potions for the sake of speed and cost and, frankly, because the average customer doesn’t know what he’s missing anymore.

On the other hand, there are some lousy bartenders out there too. Like the one who gave me a Manhattan with soda water in it once. And the one who gave me a Rum Collins which was iridescent green and had sprite or something in it (instead of just rum, lime juice, sugar, and soda water). This is probably why I normally drink beer or straight spirits when I go out; you pretty much always know what you’re going to get.

This post isn’t meant to bash the current state of the Public House though, but rather to tip my hat to my often missed homeland to the east. I’ll do this in the form of a quote from Mr. Wondrich’s book [2].

First, Wondrich quotes Victorian novelist Charles Reade from 1863: “America is fertile in mixtures: what do we not owe her? Sherry Cobbler, Gin Sling, Cocktail, Mint Julep, Brandy Smash, Sudden Death, Eye Openers.” Then he goes on to discuss the state of things today:

What survives? The Julep (once a year anyway), and the Cocktail in the form of the Old-Fashioned (although outside of Wisconsin, not one bar in twenty can make a proper one anymore).

They do make a good Old-Fashioned.

  1. Wondrich, David. Imbibe!. Penguin Group (USA), Inc. 2007. pp. 187–188.
  2. Ibid. p. 123.

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Business
Cooking

Take a Number

By Greg Ingersoll | Posted October 4th, 2009 at 15:52

I was going to write this post last week when I got a sandwich from a shop on campus. It fell off my radar until today when basically the same thing happened again at a different sandwich shop.

“Can I get your first name for the order?”

No. Give me a number. Every time someone asks for my name, I give it to them to move the process along, but invariably it all ends up taking more time than if the computer just gave them a number to give to me. Usually the experience involves some combination of background noise, poor ergonomics in the POS touchscreen, and the cashier just not caring, and I end up with my sandwich and a receipt that says “Frank” or “Rick”. This makes it especially difficult if I’m eating in and have to listen for Frank’s order to be announced over the malfunctioning PA system.

I suppose the counterargument is an attempt by management to make the shop seem more friendly. “People don’t want to be numbers,” Manager Bob might say. To which I simply reply that you’re not assigning me a number. You’re assigning a number to my sandwich. I’m ok with that, and so is my inanimate sandwich. My sandwich’s feelings are not hurt.

When I’m buying a sandwich, it’s all about accuracy and speed. Both of these can be achieved by simply assigning my order a number. And certainly don’t ask for my name and then give me one of those restaurant pagers on top of it. (This happened today.)

I didn’t go into the shop to make friends, and if I’m honest, there’s an old-fashioned—unfortunately this has become the correct adjective—part of me that doesn’t like complete strangers addressing me by my first name.

Maybe from now on, when buying a sandwich, my first name will be “Twenty.” The sandwich will arrive, and the receipt will probably read, “Tony.”

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