See you in the real world

Hey readers! 

I am sad to say that the semester is coming to an end and I will not be making any more posts on this blog.  I will leave it up for anyone to view and hopefully learn a thing or two about lasers.  Feel free to continue posting comments.  Your thoughts are useful for future readers.

I hope you enjoyed reading, and sometimes watching, my posts.  I know I enjoyed making them, and I learned a lot about blogging.  I also did quite a bit of research on lasers that I would not have done otherwise.  The experience had taught me a lot, and I hope it helped you to learn too.  Keep up your interest in lasers!  As always, stay safe!

Bidding you a fond farewell,
Benito El Jefe

Final Self Evaluation

Since the last evaluation, I have posted 17 posts with a variety of topics pertaining to lasers.

Bloggers Unite!

Hi everyone.

I read a post over at Nano Nook that deals with all sorts of cool topics at the nanoscale.  There is a post there that describes an atomic force microscope (AFM) that can be used to measure the surface topography and even chemical composition using an oscillating tip that is scanned across a material.  The technology uses a laser to accurately measure the oscillation phase (timing of oscillations) and amplitude (the distance of vibration) of the tip.  Take a look at Nano Nook's post for a nice diagram and more information!  Also check out his links that give even more detailed information if you are intrigued.

You've Heard of Laser Hair Removal...

Wait till you hear about this!

     Forensic analysts are currently using lasers to analyze hair samples at crime scenes or for drug testing.  Lasers are being used in these tests to burn the hair samples, which create hair fumes.  The fumes are sent into a mass spectrometer to determine which elements and isotopes are present in the hair.  This measurement can actually be used to extract information about the person from whom the hair originated (the hair donor).  Analysts can learn what the hair donor ate recently, and also what drugs the donor may have been using, since traces of drugs like the htc in marijuana can be detected in hair follicles for several months or even years after smoking.

     Lasers are being used to burn the hair samples, but a new method of laser hair analysis has been developed that can give even more information than the previous method.  An article at Physorg.com states that "traditional laser analysis techniques tended to obliterate entire samples as they burned all of its parts together as a whole."  This essentially eliminates the ability for analysts to determine exactly when the hair donor ate something or used a particular drug.  However, the article reports that a team of researchers have made some improvements to the technology:

"Moran and his team chose to use a less destructive type of laser that uses only ultraviolet light (similar to the kind used for LASIK eye corrective surgery). They discovered that by doing so they could essentially break apart the individual pieces and parts of the hair as a hole was bored, which could then be burned separately and tested with the spectrometer; sort of like burning the filings left over when drilling into a piece of wood with an iron bit. Because hair grows slowly over time, it creates a timeline of sorts, with different stages representing differing days, weeks or even months."

Holes can be bored down the length of the hair and the fumes from each hole analyzed separately.  Thus, timings of events can be determined accurately, whereas before the hair donor's history involved a lot of guesswork and estimations.

Morons with Laser Pointers

Remember when I told you about those two guys that went to jail for shining a laser at an airplane (see Fun and Games)?  Well they aren't the only morons out there!  I ran a search in Google for news containing the words "laser," "shining," and "arrested" to see how many people out there are getting in trouble with their laser pens.  I checked the entire list that Google spat out for the year of 2010.  I made a cumulative plot of incidents that related to idiots shining laser pointers at police, cars, helicopters, and airplanes.  By the way, some news articles did use terms like "moron" and "idiot!"  Anyway, take a gander at the figure:

There were 64 news reports that were relevant, which means that there was an average of one news report every 6 days.  Now that doesn't seem like a lot, but I was only looking at Google news reports that had particular phrases, and not all incidents make the news.  My calculations are smaller than the actual amount by a significant factor.  I found a more accurate plot from laserpointersafety.com (after all my work... should have gone there in the first place!).  These are just reported incidents though.  Take a look:

My calculations off of the figure suggest that there are, on average, 12 incidents per day for the year of 2010!  Here are some numbers that the FAA give:

• 2010: 2,836 (7.8 incidents each night)
• 2009: 1,527 (4.2 incidents each night)
• 2008: 955 (2.6 incidents each night)
• 2007: 643 (1.8 incidents each night)
• 2006: 420 (1.2 incidents each night)
• 2005: 311 (0.9 incidents each night).

There are obviously some disagreements with the plot and the numbers, but it is clear that the rate of incidents is increasing, and the yearly numbers are staggering.

These plots have shown us just how many morons with laser pointers are out there.

Bye Bye Sparks Plugs

Researchers have decided that spark plugs have got to go.  Spark plugs were invented in 1860 and have been in combustion engines and automobiles ever since.  That is a long time, and the technology really hasn't advanced since its start.

Lasers have been around since the 1950's, which is still a long time ago, but lasers have advanced a lot more than spark plugs have.  That is why researchers are now interested in replacing spark plugs with lasers to ignite fuel in combustion engines (source).  Previously, lasers were too fragile to withstand the harsh environment in the engine, but now lasers can be made out of tough ceramics.  These ceramics can survive in engines, and the lasers add some benefits over spark plugs:

Spark plugs use electrodes that corrode with every spark.  Lasers don't have this issue.  They just blast an intense laser beam into the combustion chamber and let the light do its work.

Spark plugs are positioned on the side of the combustion chamber, so the fuel is ignited unevenly which causes inefficiency and creates more pollutants.  Lasers can be sent straight through the center of the chamber to evenly ignite the fuel, bypassing those drawbacks from spark plugs.  Additionally, several lasers can be sent into the chamber to increase the uniformity of ignition.

Spark plugs can be ignited precisely within a few milliseconds, whereas lasers can be controlled down to the nanosecond.  This precision allows greater control over exactly when the fuel is ignited, which helps to increase efficiency.

Clearly, lasers are the hip new way to rotate your wheels.  Let's hope they work the wonders that I have stated here!

Wait. What?

I read an article at Techland that has me in disbelief.  I am a bit skeptical of what they are reporting, but I have no facts or evidence to say they can't do what they claim.  You need to take a look at the article and tell me if you believe the reporter.  Tell me if you think a laser could be made that produces more power in a single beam than all of the world is using at any moment.  I bet some of our friends in the electrical energy industry will say it can't be done.

I might be able to believe it if the beam is emitted in a very short pulse.  Remember, power is a rate.  Maybe that kind of power can be produced for an incredibly short period of time so that the total energy consumption is in the believable range.

Glow in the Dark

Remember way back when I told you about fluorescence?  Well there is another funny phenomenon called phosphorescence, and it's the secret behind all of your glow-in-the-dark decorations and toys.  You probably even know a little about how they work. 

Think about it.  When you look at the object in the dark, is it always glowing?  Not if you didn't leave it in the lamplight before you turned off your lamp!  That's because you have to "charge" the phosphorescent material up like a battery.  This "charging" happens optically.  Light from your lamp hits the atoms in the material, the atoms become excited and reach what is called a "triplet state," where the upper state lifetime for the atom is quite long (minutes or hours).  There is a bit of quantum mechanics behind it all, but the previous description is just a fancy way of saying the atom is storing the energy for a while before letting it go. 

When many of the atoms are charged, and you turn off the light, some of the atoms start spitting out their energy in the form of light.  This continues to happen until all of the atoms have released their energy.

How does this relate to lasers?  Well a laser can be used to charge a phosphorescent material super fast, since the laser is so intense and blasts all of the atoms in the material to their triplet states.  Check out the video below to see this in action!

Lasers help to free you from your demons

You were a teenager!  You were young, irresponsible, and wanted something to show off.  Getting that tattoo was the natural thing to do!

But now you are getting tired of putting lotion on it, and the image is blurring, and you are afraid of what will happen when you get wrinkles.  Maybe you are becoming a different person, and that image of the devil just isn't you anymore.  Maybe "Jessica" dumped you, and you want to erase every memory of her.  Whatever the reason, you want your tattoo gone.  Well take a look at this video, where a man came to a similar realization and is using lasers to help him get rid of his demons [source].

Laser Powered Cars!

 Can you imagine that?  Well your cars may someday be driven by lasers!  ........... indirectly.

     A new application has been considered by the Argonne National Laboratory where lasers drill the wells to get to oil and natural gas.  Here's how this works:  A fiber optic cable sends high powered laser pulses (nearly as powerful as the Navy laser) down a shaft to blast away rock, and then the rock is carried to the surface (by using drilling fluids or another method).  As you can imagine, this takes a ton of energy, but it can actually be less expensive than current drilling methods.  Current methods already require a lot of energy, and drill bits need replacing every so often.  That isn't true for laser drills.

     The Argonne Laboratory is actually working with the Colorado School of Mines on this project.  Dr. Ramona Graves in the petroleum department at CSM is in charge of research concerning laser-rock interaction, which exactly relates to this project.  So there are definitely efforts to get this technology ready for use in the field.

What you can't see CAN hurt you... but can be pretty useful...

As I showed in my video blog in my last post, infrared light is invisible to the naked eye.  You can detect its presence with an infrared viewer or infrared camera, but not many people carry those around with them.  My green laser pointer emits infrared light in addition to the green light.  This can be dangerous because that infrared light adds to the power of the total beam, and it makes the beam more capable of causing eye injury.  That means the user has to be extra careful to not shine the laser toward people.

Infrared light isn't all bad though.  Many high powered lasers, like CO2 or Nd:YAG lasers, use infrared light (a lot of it) to cut through materials.  For CO2 lasers and Nd:YAG lasers, the output wavelength is 1064 nm, which happens to be the same wavelength of infrared light that my green laser pointer emits.  The Nd:YAG laser is used for 3D engraving.  Check out the video below to see how that works!

What else can infrared light be used for?  Here is a project for those do-it-yourself-ers out there!

*************** AS ALWAYS, SAFETY FIRST! ***************

You can order an infrared laser* or LED (or buy a green laser pointer like mine and block only the green) and shine it toward an IR photodiode.

So what?  What does this accomplish?

Well the photodiode will sense when the laser is shining on it AND WHEN IT ISN'T!  If an object or person passes through the laser, the photodiode will know!  People won't be able to see the beam or spot on the photodiode, so the system can be used for security purposes.  Ever see laser trip alarms in movies or video games?  This is how they would work!
 
*You could get away with a cheap red laser.  Check out this link that shows the steps for the DIY project.

Many garage doors have a system like this (probably using an infrared LED) to detect whether there is an object or person under the garage door as it closes.  You have probably seen this and may have, like me, had to jump over the beam while ducking your head if you want to close the door and get out at the same time!

The secret behind green laser pointers -- VIDEO BLOG

I took a trip down to the laser lab to get the scoop on my green laser pointer.  The following video documents my journey:

The take-home message?  Just because you can't see the infrared doesn't mean it isn't there.  It can burn your eyes just as much as the green can.  Just keep that in mind if you get your hands on a cheap green laser pointer.

For your reference, here is a chart of the electromagnetic spectrum, which shows where visible light is, and where infrared light is in relation to each other.

     The three spots we saw in the video were the separated colors of light from my laser pointer.  The left spot was green (532 nm), the faint middle spot was near infrared from the pump (808 nm), and the right spot was the infrared (1064 nm) that gets frequency doubled to green.  Here is the picture in the video showing the steps taken to produce the green light:

 

     In the video, I refer to an "infrared camera," but the tool I use is actually called an infrared viewer.  The combination of the viewer with my camera, though, does imitate an infrared camera!  So my verbal mistake wasn't too far off.  Also, the video alludes to a nonlinear crystal that converts infrared light into green light.  This is a fancy way of saying that the atoms in the crystal absorb reddish-colored light and emit green-colored light.  This happens through a nonlinear process, and needs to happen because there are cheap materials that naturally can be used to make an infrared laser.  Only recently has there been success with true-green emitting materials, as I report in my 3OH!3 post.  I discussed a little about nonlinear processes in Adding and Subtracting for those who want to learn more.

Take a look, and enjoy the cool things I demonstrate in the laser lab!  And definitely ask me questions if you have any!

FOX catches on...

     It looks like a reporter at FOX News has stumbled on the story about the Navy laser project I have been posting about.  The FOX report includes some details about the Navy maritime laser demo, the free-electron laser project, and a rail gun project they are working on too.  On FOX Nation, they also show the maritime laser demo video I posted in Navy laser demo.

I actually noticed a problem in the FOX News article about the free-electron laser.  In the article, they say,

"Called the FEL -- for free-electron laser, which doesn't use a gain medium and is therefore more versatile -- it was tested in February consuming a blistering 500 kilovolts of energy, producing a supercharged electron beam that can burn through 20 feet of steel per second."

The problem is that they claim the laser produces a "supercharged electron beam" which is what burns "through 20 feet of steel per second."  If the reporter had researched free-electron lasers, he would have known that the laser does produce an electron beam, but the beam oscillates causing the emission of an intense beam of photons, or a laser beam.  It is the intense laser beam that does the burning, and not the electron beam.

     I believe this inaccurate reporting, even though it seems like a small detail, is due to the fact that the FOX reporter is most likely not a scientific journalist, and so he did not understand the science in the first place.  There is another possible reason for the misreporting; the reporter might have believed that readers would not understand the science, so he simplified the science to focus on the big picture.  However, scientific journalists are much rarer nowadays than previously, so the first hypothesis is likely the correct one.

     I am also interested in the rail gun report seen in the FOX article.  It appears the Navy does not believe the rail gun will be ready until 2025.  Yet, there have been references to rail gun technologies in older video games (Metal Gear Solid, in which the big bad machine is equipped with a rail gun) and movies (Transformers 2, in which the Navy takes down a giant machine on top of a pyramid with a shot from a rail gun).  Word gets around, I suppose.

Navy laser demo

     Remember that laser the Navy was working on?  The one that cut through ridiculous amounts of steel per second?  Well check out this video I found at geek.com.  It shows a lower powered prototype of what they are after.

The article at geek.com describes more about Star Wars efforts, the Navy laser, and the Boeing laser that I have been posting about.  Looks like someone else is interested in this stuff too!

There is also a 5 minute Navy PR video concerning the laser system in the following video, for anyone interested in the Navy laser defense systems.  The PR video explains the Navy's goals and has some nice footage of takedowns.

The Power of the Sun

     The sun is an amazing thing.  It allows us to live on this Earth by heating the planet from 93 million miles away.  The sun uses fusion to do this.  Fusion is the process by which Hydrogen atoms combine to form Helium atoms - a process that happens to release a large amount of energy.  Across the globe, there are efforts to control the immense power of fusion to supply the world with energy.  But there is a catch --- How are we supposed to even induce fusion in a controlled manner?  The H-bomb needed fission explosions to provide the heat and pressure required to induce fusion.  Won't our efforts to start a fusion reaction end in destruction if we use the H-bomb technique?

     That's where lasers come in.  Small amounts of fuel can be heated and pressurized through the use of lasers and some other structures.  There are two methods to control fusion that are being researched currently:  Inertial confinement fusion (ICF) and magnetic confinement fusion (MCF).

     ICF uses a pellet of Beryllium and isotopes of Hydrogen (the fuel) filled in a gold cylinder.  Lasers hit the outer layer causing it to explode, creating huge shockwaves, high pressure, and immense temperatures inside the cylinder.  An IOP article states that an experiment at the National Ignition Facility shot 192 laser beams at one of these cylinders to produce temperatures up to 3.6 million degrees Celsius!  That's hotter than the sun, people.

     MCF uses strong magnetic fields to create a "magnetic pressure" on the plasma of the fusion reaction.  Other methods besides using lasers are used to heat the plasma in MCF.

     Fusion is a seriously cool topic, and it is amazing how lasers can be used to produce such extreme conditions to induce fusion.  How many people can say they have mimicked the sun with their research?  Not me, but maybe someday!

Laser welding

     I knew there were tons of applications for lasers in industrial settings, but I was unaware that laser could be used to weld metals.  Cutting?  Sure.  Drilling?  Duh.  Scribing?  Of course!  Welding?  Wow.

     With all of the videos I've posted and stories I've told about lasers obliterating whatever they hit, I had no idea that the heat produced could be controlled to fuse two metals together.  A story at FEN describes how lasers can be used to weld "titanium, beryllium, copper, and platinum," materials that cannot be welded by traditional methods.  Not only that, but the narrow beam of the laser can create incredible welding precision.  The only downside is the cost, but the technology is reasonable for certain welding types and large scale production.

Another application to add to the list!

E-Days Let-Down

     The end of last month brought to all of the students at the Colorado School of Mines what they had been craving for all year.  That's right.  E-Days!  And along with it, comedians, a concert, chances to win prizes, competitions, activities galore, and, of course, the laser light show!

Wait.... Laser light show?  What about the fireworks?  No fireworks?  WHAT???

     The thing that really gives CSM students a thrill that will last them until next year, the amazing fireworks display of E-Days, WAS CANCELED!  Replacing it was a laser light show that would normally get a laser physics enthusiast excited.  But this laser show was far from phenomenal.

What made the laser light show so bad?  Here are just a few concerns I had:

1) The school was ill-equipped.  There were only four, stationary laser projectors, two of which only emitted green lasers.

2) The animations were neat at first, but it was clear that they were put together hastily.  Parts of the animations were just stationary outlines that slid across the screen, an underwhelming element of the show.

3) The music selection was terrible.  Classic rock did not mesh well with a show that inherently felt like it belonged at a rave.  People got up and danced to the single pop song that was included, but the urge to dance evaporated for the rest of the show.

4) The attempt at sex appeal was so terrible, it was less than laughable.  The producers apparently thought that poor outlines of women roller skating and doing strange dances would turn on the viewers.  I felt embarrassed just to watch it.

5) The scanning of the lasers through the fog was neat since the air currents added a dynamic experience to the effect, but the novelty of the stationary scanning soon wore off.  

6) Saying the laser show was a replacement for the fireworks would make any CSM student feel wronged.

     I'm not saying the show was that terrible.  I know a lot of effort must have been put into making the show as good as it was.  I could have done no better myself.  But there was just a feeling of monotony and awkwardness to the whole thing.  The technology was all there, but its implementation was lacking a professional touch and a fitting musical environment.

All I can pray for is some rain so that the fireworks will be allowed once again.  Then things may be right in the world once more.

Stay away from the ocean!

     This post is a sort of follow-up to my last post, Death Rays.  I found an article at dvice.com that described a laser project that the Navy is working on.  The Navy has designed a pretty incredible free-electron laser (free-electron lasers are pretty cool, and you can check out how they work at Wikipedia.).  The article says that the Navy laser "produced a 200 kilowatt beam capable of burning its way through 20 feet of steel per second."  Holy crap!

     That's not all.  The article claims that the Navy is trying to build a laser that will do 100 times as good.  That's right; cut through 2,000 FEET OF STEEL PER SECOND.  Now I know you're thinking, "death rays are as good as real with that kind of technology!"  Just imagine if you sent that thing into space, along with one of those programmable mirrors that they put in laser TVs to direct the laser.  There's your death ray. 

Here's the only problem with that:

     The 20 ft steel/sec laser was the size of a football field, and can only, as of now, fit on a Navy aircraft carrier.  No other vehicle could hold the thing!  Imagine how much power it takes too.  So putting one of these in space is not probable, which means satellite death rays are a ways off.  However, the article reassures us that,

"as improvements in technology enable the laser to shrink, it'll also become more efficient, and by 2015 the goal is to get it down to 50 feet by 20 feet by 10 feet. And by 2020? It might be smaller still, able to fit into helicopters and drones, and it's not too much of a stretch to imagine something small enough to be handheld by 2030."

     That sounds like a world I would want to live in!  The one where terrorists with helicopters could blast through buildings and houses from a distance in a few seconds.  Airborne Gatling gun times a billion!

     I am a bit skeptical about the availability of handheld lasers that are this powerful even by 2030.  Think of the battery that would need to be on them!  The one I show in They're Out There only gets 30 shots, is a little bulky, and is waaaaaaayyyy less powerful.

Still... the fact that these projects are being developed is a little scary.  This stuff might actually end up working, and that might not be a good thing.

Star Wars! Death Rays! THE END OF THE WORLD!

     You have got to see this!  I found an article from the St. Petersburg Times, and several related ones from other sources, that describes an attack on U.S. satellites from Russia!  Here is the excerpt:

     The article is from the November 22, 1976 issue of the St. Petersburg Times newspaper.  According to the article, in 1975, Russia took out two U.S. satellites with a high-powered laser beam.  Scary, huh?  Especially the part about "hunter-killer satellites" and "death rays!"  Well, those predictions that the magazine made were pretty wild.  To my knowledge, we don't have "death rays" even today.  The only thing that comes close is the Boeing laser from Weaponizing Lasers. 

     This is a perfect representation of what journalists will say to get their story heard (and an interesting look into past journalism too).  The blinding of the satellite really boiled down to some burning (similar to the video in Weaponizing Lasers) on the satellites sensors or transmitters.  The image that comes to mind when reading the article, however, is that the laser completely annihilated the satellite!  I mean, the laser beam was "10,000 times as strong as a natural blaze!"  Wouldn't that be like an explosion, if a natural blaze is taken to be a small flame?  An excerpt from the Nov. 22, 1976 issue from the Milwaukee Journal said that the beam could "vaporize metal and produce destructive shockwaves."

     Wouldn't the reader get a sense of fear from this article, especially back in 1976, when the average man's understanding of lasers was not at all like what it is today.  People could not do a quick Google search back then to see how far lasers have come.  All they could do is imagine an evil Russian scientist sending a laser into space and killing every American that went outside!

I just found this interesting science communication about lasers from the seventies.  Pretty far-out, huh?

Self-Evaluation #2

     Since the last evaluation, I have altered the content and writing style of my posts to attract a wider audience.  I have attempted to make my posts "newsier" by searching for news articles related to lasers to find something new and exciting.  I have especially focused on controversial use of lasers, such as for weapons.

Maybe Not Such a Waste {rev}

     I am going to have to apologize for the last post.  My sarcasm seemed to bleed out of that one, didn't it?  Well I just felt I needed to respond to a certain incident.  It went like this:

     I used a laser pointer in a presentation for a class, and the next week, an experienced presenter demonstrated how awful laser pointers are when used in presentations.  He imposed his view on the entire audience, and I am sure many of them will take his words as truth since he is an experienced, intelligent presenter.

     Everyone is entitled to their own opinion, but there are so many successful people out there that use laser pointers in their presentations.  Take Nobel Prize winner Eric Cornell, for instance.  He gave a presentation at the National Institute of Standards and Technology - NIST - (Hey! I worked there last summer!) concerning Bose Einstein Condensates.  Here is a snippet from the transcript:

"Bosons, on the other hand, love to all do the same thing. For instance, in this laser pointer which I hold in my hand, there are a tremendous number of photons first bouncing back and forth inside it and then spilling out one end. They are all going exactly the same direction with the same energy."

     Wow.  Even a Nobel Prize winner uses laser pointers.  And it's not just him.  During my summer at NIST, many of the employees utilized laser pointers as presentation tools.  Laser pointers were provided to the summer interns for their research presentations.  Employees could even buy laser pointers with the NIST label right on the side (for $90 no less, and they were selling!).

     So that is why I wanted to support the use of laser pointers.  I know the use of laser pointers in presentations is a matter of preference.  Of opinion.  There are those that think it is distracting (and of course it would be if all people were cats!).  But many individuals... successful ones at that... think it helps to direct attention and aid a presenter.  I just hope people will think for themselves and make up their own mind about whether laser pointers are helpful or not, instead of taking one person's views as truth.

So I will stick by my laser pointers, even if there are those that disagree with me.

Don't Waste Your Money

     I got duped!  I wasted my money on useless laser pointers!  What was I thinking?  Laser pointers have no purpose!  What are the possible applications for these scamalicious products?

1) Pointing at Presentations
2) Stargazing
3) Blinding Pilots (or anyone for that matter)

     But are these applications even useful?  How about laser pointers used as a presentation tool?  According to some professional speakers and presenters, laser pointers actually detract from the message by dazzling the audience like they were cats. Sloppy presenters might even shine the laser into the eyes of the audience, combining the problems with applications 1 and 3!

     Stargazing?  Now that isn't really an application.  After all, who even goes outside to look and point at stars nowadays, let alone try to map them?  All the ones we can see with our eyes or low-end telescopes (even without city lights inhibiting this hobby) have been mapped already.  Besides, shooting a laser in the sky can land you in jail if you end up accidentally taking part in application number 3...

     Attacks on pilots with laser pointers have increased across the nation, and the act is now considered a federal crime.  Laser pointers are a tool that evil people can use to ruin the days of innocent pilots and travelers.

     So why own a laser pointer?  Why even allow companies to manufacture them?  They are only good for destroying presentations, eyes, airplanes, and your wallet. 

.........Right?

They're Actually Out There!

     I have to admit it.  I was wrong.  I received a comment on an earlier post, Weaponizing Lasers, concerning high powered lasers in the hands of average people.  I expressed my skepticism of that happening anytime soon due to my belief that hand held laser weapons would require a huge power supply.  Well I guess I should stop expressing my doubt about laser terrorism because it seems like those laser guns from Star Wars actually exist!  Check out this website that shows a laser gun prototype and a video of its operation.  I have included the video below.

     The "plasma ball" seen in the video is, I believe, an example of filamentation.  Filamentation occurs when the intensity of the laser is so large that the laser actually causes the air it travels through to mimic a lens.  This occurs because the laser heats up the air in a special way.  In the end, the laser self-focuses, and becomes even more intense!  Now, the laser's self-focusing also has to fight diffraction (the photons' desire to be spread apart from each other), but if the laser is strong enough, the light will cause the air to ionize, like the gas in a fluorescent lamp.  Voila!  "Plasma ball!"

     Also notice in the video that the gun was supposedly purchased.  That means there is someone out there who wants to use it for one of three purposes:

1) To use it for fun,
2) To use it for evil purposes,
3) Or to use it to accessorize a Star Wars costume.

Let's hope it's not #2.  If the laser can filament, it can blind, burn, sear, scar, sting, zap, and tingle.  Those laser issues at airports.... Well those might be just the beginning....

Laser Hype: Aliens, Star Trek, Geeks, and BBC

     When I was abducted by aliens, I experienced a trip through something called a tractor beam.  After my traumatic encounter with the aliens, I have decided that it is a good idea we start developing our own tractor beam so we can give the aliens some payback one day.

     Back to reality.  Of course, I was never abducted, but I found a few articles {India Times, Geekologie, BBC} that describe lasers as the key to creating tractor beams.  The first article describes a Bessel laser that has the ability to pull small objects toward the laser source.  However, the physics behind the phenomenon was poorly described in the article.  I find this to be a result of the scientist-journalist communication gap.  Apparently the author of the article did not deem the specifics behind the Bessel laser to be of much importance, or he simply did not understand it.  For a reader like myself, I had a hard time believing the vague explanation that was provided.

     The first article left me wanting.  I needed to learn more about the physics behind lasers as tractor beams.  I found my way to the second article, which describes not a Bessel laser, but a hollow, or ring, laser.  Particles in the center of the ring can be kept in the center of the ring due to the higher temperature surrounding the particles.  This method can be used to create an "optical trap" for particles.  Optical traps are used in many experiments, such as ones involving Bose-Einstein condensates.  The trap can be translated to move the trapped particles.  Nevertheless, I found the trap is less like a tractor beam than the Bessel laser was claimed to be, so I moved on.

     I finally arrived at the BBC website that mentioned both technologies but gave more detail and analogies for the Bessel laser.  In the end, it seems that Bessel lasers can only pull small particles tiny distances.  The optical trap method has been able to move a cluster of particles over longer distances, like five feet.

Tractor beams?  Not yet.
Someday?  Maybe.
Hype?  Absolutely.

     The technology and idea is very cool, but its applications as of yet extend only to a few feet for a small mass.  The titles of the articles I researched gave the impression of a large scale, UFO style tractor beam.  Even the content said the beam would soon be used for large scale applications.  That's hype if I've ever seen it.

Now let's go kick some alien butt!

Off topic, but I can't resist!

     I recently read a chapter from Stephen Schneider's "Science as a Contact Sport" for my Communicating Science class.  While I was reading, I started to become annoyed at the bias that was painted all over the first half of the chapter.  It was clear to me that Schneider disapproved of Conservative views and opinions, and he made a large effort to discredit those views.  Fortunately, he began to let up on politics and make arguments about the flaws of the media and about effective science communication.

     After reading the chapter, I watched a clip from Al Gore's "Inconvenient Truth," of which I had only seen a little.  I have to say that I was beginning to get tired of listening to one side of the story.  I then watched a video of Glenn Beck to satisfy my desire for balance.  It is true that I was getting some of each side, but those videos were probably not the best ones to watch to better understand global warming.  They are epitomes of extreme reporting.

     After it all, I am not sure which data to believe.  I might have been able to glean some truth from the issue had I been exposed to a more moderate view on global warming.  One that showed the many opinions on the matter and commented on the credibility of each view --- a concept that Schneider advocates in his work.

     I found the investigation into global warming enlightening, but I am personally more interested in other topics.  Laser physics, sports, and entertainment especially interest me.  Concerning the global warming issue, the following compilation of video clips is one that I would prefer to watch.

     There isn't a lot of truth in those clips, and all of them mock or belittle the serious issue, but I still get a kick out of them.  Just realize that none of this should change your opinion on climate change.  Look somewhere else for valuable information.

DIY Holograms

     I took a look at the poll that I posted a while back, and it seems that the majority of people agreed that DOING THINGS led to the most effective learning.  My intent was to change my writing to take your opinions into account.  This is my attempt:

     If you want to learn more about light, but you don't want to read about it, you can perform your own experiment!  Look at this website.  It shows you how to make your own holograms.  You are probably thinking, I don't have time for this!  Never fear!  I tried making my own holograms, and it only took a few minutes to get a result!  It really is easy and quick to do.  The only things you need are a piece of plastic (like from CD cases or the packaging of many electronic devices - phones, videogame accessories, etc.), a compass (EPICS anyone?), and a design that you want to create in the hologram.  Follow the steps at the website and then go out into the sun (or use any point source - a laser pointer in a dark room for instance).  Enjoy!

     If you are wondering why the image appears beneath the surface, it has to do with the fact that your eyes are spaced apart and because the scratches that are made on the plastic surface act like a grating.  The grating causes interference in the light, and only the image you have designed is allowed to reflect toward your eyes.

If lasers could talk

     If you have been following my posts, you have found that there are many applications for lasers.  I have provided a list of medical applications and I have alluded to industrial applications.  I have even shown that lasers are similar to cute little ducks.  You may think I am just a laser enthusiast, claiming that lasers are completely amazing, useful, and awesome.  But I have shown that lasers are being considered for use as weapons and I have remarked on a story of laser misuse.  So maybe lasers are not so appealing.  Maybe the technology should be avoided due to the dangers that are associated with it.

     I found a news article that showed another medical/cosmetic application of laser technology: an anti-aging laser technique.  The report describes how lasers can be used to eliminate bulging, unsightly veins.  The article emphasizes its use on older women and, especially, celebrities.

"A small ‘pinhole’ puncture is made into the vein and a tiny catheter - no larger than one millimetre in diameter - is inserted along the length into which more anaesthetic and the laser is placed. The laser is activated and slowly pulled out of the vein. The heat from the tip of the laser seals the vein closed, diverting the blood supply to other, deeper, less prominent vessels below the skin’s surface.... After a few days and weeks the treated vein is reabsorbed into the body and disappears completely."

     From this description, I cannot decide which category this application should be placed into.  Cool app?  Or body ravager?  I am of the opinion that those veins are in your body for a reason.  Wouldn't destroying them result in poor circulation to your limbs, or possibly have some side-effect like lack of feeling near those areas?  If those effects don't result from this technique, then I could see the appeal of this application.  Cosmetic operations are all the rage now, so this might be another one, not to mention a possibly safe one, to add to the list of ways you can change yourself.

     What is your opinion of this application? I find it hard to decide how to classify this one.  For me, it's kind of in the gray area between useful and dangerous.  Maybe that is the thing about lasers, or science in general;  not every technology has to be clear-cut right or wrong.  If lasers could talk, they would probably say, "I'm a laser, not a saint."

It's All Fun and Games...

     I found a report of two men that decided it would be fun to point their laser pointers at aircraft.  This kind of thing, although it may seem like innocent fun, is pretty serious.  The report describes the maximum penalties the two pranksters can be charged with:

8 years in prison and a $15,000 fine!

     Even though laser pointers can be fun to play around with, pointing them at particular things, like landing aircraft, vehicles, police officers, and people in general, is serious.  What was meant to be a joke can easily turn into a disaster, in the form of serious injuries, deaths, and/or criminal charges.

     I want to emphasize to my readers that if you ever find as much interest in lasers as I have, use your head before you aim your personal laser.  You might want to avoid handling high power laser pointers because accidentally pointing it at a reflective surface can lead to unexpected eye injury.  Typically, 5 mW laser pointers are safe because our blink reflex prevents too much damage to our eyes.  Still, don't point them at people or vehicles.

If you call in the next 10 minutes...

     Ever wonder if lasers would find their way into infomercials?  Well wonder no more!  These infomercials I found are exactly what you were looking for!

 Ok.  So I didn't find these infomercials.  I modified existing ones to advertise lasers (if that wasn't obvious to you) {sources 1, 2, 3}.  But why shouldn't there be laser infomercials out there like these ones?  I haven't run into any!

     The reason for this is because applications of laser technology are not gimmicks.  They actually work.  There is a pretty long list of laser applications in all industries.  Pertaining to health and medicine, here is a list of just a few that I know of:

Hair Removal
Stretch Mark Treatment
Scar Removal
Tattoo Removal
Teeth Whitening
Acne Treatment
Vision Enhancement Surgery
Bloodless Surgery Cutting Tools

     If you were thinking about getting any of these done, don't search infomercials to find a solution.  Be thankful that scientists and doctors are cooperating to extend the applications of lasers to cosmetic and health applications.

More on Weaponizing Lasers...

I found this video that gives a more detailed explanation of how the airborne lasers can target and destroy launched missiles.  Enjoy!

Lasers are like Ducks.

     Hey check out this video!  Those ducks are so cute!  Just watch them swim in the water, making a splash!

Adding and subtracting shouldn't be this hard

     We all know how to add and subtract numbers, even if some of us avoid doing so by becoming good friends with our calculators.  Performing addition and subtraction on numbers is one thing, but what about doing the same with light?  Specifically, can we add and subtract photons, light particles, from each other?  Does this seem possible?  Photons are essentially light particles.  Try taking two particles of matter, like a piece of your computer or even the air you are breathing, and combining them to make one particle.  Only nuclear reactions do this, and to tell the truth, how easy is it for us to mimic what the sun does?  Well we can combine two light particles together to make a single, different light particle.

Blog Self-Interview

A moment of self-reflection....

Q. What is the purpose of this blog?
A. The purpose of this blog is to communicate the science behind lasers and their applications to an audience that may have an interest in the subject but would like to know more.  I would also like to communicate some more complicated ideas that typically require a background in laser physics to understand.

Q. Who is the imagined audience(s) of this blog?
A. My intended audience consists of curious individuals that have wondered about lasers, as I have since I was young, and want to know more.  I try to include fun pictures for more visual audience members, and news stories with a short analysis for those more political- or physical-minded individuals.

Weaponizing Lasers to Reduce Casualties

Contradicting?  It may seem so...

     Ever since the proposal of "Star Wars" during the Cold War, there has been a lot of interest in utilizing lasers as weapons.  Now, Boeing has released footage of their airborne tactical laser.  The test shows the laser scorching the hood of a truck from an airplane, and Boeing states that the truck was "disabled" off-camera.

     With this kind of power, these lasers could take out human targets from the sky and change the dynamics of war.  Just knowing that there is a sniper laser in the sky would have serious psychological effects on targets.  The advancement of such devastating weapons can get a little scary at times.  Often, one has to ask the question, "How does this help?"  Aren't these advancements perpetuating and promoting violence? 

Books prevail over public dialogue, despite their suckiness

Reading.
Some love it.
Some hate it.
Some, unfortunately, don't know how.
You do, though, so let me tell you a story and maybe you can help me resolve some questions I have about the subject...

Fluore-what?

     If you have read my previous posts, you know the basics of laser operation.  As usual, you can always get more information at the Wikipedia Laser page.  Now let me tell you about a neat phenomenon about certain materials called fluorescence.  When light hits a fluorescent material, the material can shine a different color.  This happens because the light that hits the material excites the atoms.  These excited atoms then release their pent up energy by releasing a different color of light than first hit the material.  The light produced is closer to the red side of what we can see as opposed to the violet side (remember ROYGBIV.  Take a look at About Physics for more info on the visible light spectrum).  You can think of the excited atoms as balls rolling up and down hills, a metaphor I use in my post “Can I make a laser from a flashlight?”  I demonstrate the wonder of fluorescence by using my violet laser pointer to excite various fluorescent materials, which glow a different color in the picture below:

Pretty cool, huh?  Fluorescence is the process that causes objects to light up under black lights.  So next time you go to a rave, you can tell all your friends there exactly why your bleached-white t-shirt and highlighters light up.

Can I make a laser from a flashlight?

 The colors of the laser rainbow on my skateboard.

     Since I was young, I always wondered how lasers worked, and if I could make one by poking a hole through a piece of paper and shining a flashlight through the hole.  I'm not sure if anyone has tried this, but I did.  What did I find out?  Wouldn't lasers be called "constrained flashlights" or something else if that worked?

Introduction

     Welcome to my blog on all things laser.  I have created this blog for a Communicating Science class I am enrolled in.  I will lead you through some very interesting physical concepts while describing the applications of laser that have been and will be seen.  Get ready to learn about a really fascinating topic while enjoying the fun that can be experienced in association with lasers.  There are a number of many other science-related blogs that can be found at my professor's website.

3OH!3 Consults Laser Physicist and Taxidermist

     Colorado electropop sensation 3OH!3 has been touring the nation, spreading their catchy beats and controversial lyrics to an ever-increasing fan base.  Accompanying them on their trips is a pair of  laser-eyed wolves that join the band on stage to surprise the audience with a laser light show during concert performances.  No doubt, a bit of taxidermy art was necessary to provide the two band members with the wolves, and the relatively recent development of compact lasers would give the pets laser-vision.