How Lasers Actually Work

I’ve been digging lately, looking for the next thing to wow my photon brain…  there’s been some LED developments and some other manufacturing-based tech dev that has been cool, but when you see something that peaks your curiosity, you’ve often got to go way back to the starting line and stretch.

Here’s some mind stretch for the photonics world — How Lasers Actually Work:


This article is from one of my favorite blogs, Hackaday.  It’s in your face.

From Wikipedia --

From Wikipedia —

And that is a big-ass Carbon Dioxide laser lasing and igniting a target.  Boom.

You know what blows my mind about lasers?  It’s just light.

This plywood is being cut by light.

This metal pipe and stuff?  Light.

Allllll light.

This is also all light:


Some companies and websites to check out:

X-Laser, who makes pretty bad ass laser packages for our industry
Pangolin, they make some interesting laser control software/hardware
Showlasers, a Dallas company that does some pretty amazing stuff
Edmund Optics, just get on their catalog list, they have the coolest freaking optics catalogs
Schaum’s Guide to Optics, probably one of the best optics books I’ve read
Real Genius, with Val Kilmer, one of the best nerd movies of all time, about lasers

STOP Aiming Lasers at Pilots, Stupid Bastards!

PEOPLE!  People.  We have to talk.

Over the weekend, there was an incident that caused a flight out of London to turn around because the pilot had experienced a laser beam in the eye from the ground somewhere.  Here’s the recording from the cockpit with the control tower with the crosstalk about the First Officer being hit in the eye by a laser:


Do you work with lasers?
Do you play with lasers?
Do you have a pen laser?
Do you like it?

Here’s a list of your local laser laws and regulations.  It might be time to bone up.

Pretty soon, if the bullshit keeps up with the pilots and shining lasers in their eyes — we, as in you and me here in the United States (and potentially worldwide because the rest of the world doesn’t play the crap like we do) will no longer be able to have these pen lasers.  The laser industry will suffer; laser consumerism will suffer, and creativity from lasers and playing with lasers in the darkness and all of the fun that entails will be a thing of the past, and you will knock the progression of lasers as a tool of learning and fun right out of whack.  See what’s happening to consumer drone use right now??  I foresee some really non laser-positive things happening with respect to laser legislation in our very near future if this keeps up.

What happens when you do something like this is that you instantly create a panic — and when people panic, news stories like this come out:

See, this is what happens when we can't have nice lasers

See, this is what happens when we can’t have nice lasers

It’s a shame, really.  It’s so much fun to shine lasers into the night sky, given the proper permitting and all of that.  In some places they show right up at your house when you shine your laser up in the sky, it’s uncanny how well law enforcement has gotten with respect to laser source tracking using socio-economic data in tandem with location tracking to find out who might have had the errant laser.  But there is no time and no laughter coming from the US Government on lasers and planes, even when having one of those Star Shower things…

The Star Shower is essentially eye-safe, and does not cause direct interference (glare) with pilots’ vision after about 411 feet. However, a single beamlet can be a distraction to pilots at least 3/4 of a mile away, and possibly further away due to the large number of laser dots aimed into the sky causing a flashing effect.

For this reason, a Star Shower needs to be aimed so that beams don’t go into airspace. You do not want an officer knocking on your door because a pilot saw and reported your home laser projector. While it is unlikely you would be arrested for an unknowing aircraft illumination, federal penalties for laser pointer misuse range up to five years in prison and up to a $250,000 fine.

Putting the projector closer to a house will keep more of the beams on the structure. Similarly, don’t aim it up into a tree unless the tree is very dense, such as an evergreen.

It should also be noted that there are reports such as this and this of Star Showers being stolen from yards. If you put your projector on a roof or up in a tree, aiming downwards, this both helps aviation (no beams going up into the air) and makes it harder to steal the projector. Finally, if you are in a heavy air traffic area, you might want to consider restricting it to indoor use only.

DAMMIT! You're screwing lasers up for everybody!

DAMMIT! You’re screwing lasers up for everybody!

The FBI and the US government has no humor and no tolerance for this behavior, it literally is a felony to shine a laser at a plane because, if you’re caught, you’re more than likely going to be charged with a felony — the government considers this interfering with the operation of an aircraft, which comes with a door prize of a 20 year prison maximum and a $250,000 fine.  Again, there is no humor or time for this, and every reported case is another instance some lawmaker is going to use to really put a bind on lasers for the normal nerd.

What is going to happen now I suspect, since the British Airline Pilots Association (BALPA) is good and angry about its most recent experience this last weekend with a first officer being hit in the eye with a “military grade laser” on a flight form Heathrow, is that everyone is going to panic, and people across the world are rushing to judgement because any time we can’t fix something or perhaps don’t understand something, we legislate the piss out of it so that it becomes harmless to everyone.  If the plane laser strikes keep happening and whomever out there doing this keeps it up, not only will everything laser become more expensive, but so will the cost of legally being able to own it, especially with some of the higher laser classes.  Thanks for nothing, y’all.

Laser strikes doubled from 2014 to 2015.  DOUBLED, both per day and per the whole year .  Why?  High-power laser pens are everywhere, and are cheaper than dirt.  Also, people who are stupid are going to do stupid things:




So, with that being said, seriously:  stop doing this!

A Laser Enthusiast and General Nerd of Light

Extra nerdery for your benefit on this topic:

A Video Introduction to Nanophotonics

Have you ever heard of Nanophotonics?  It’s also called nano-optics — things like laser communication, optimizing solar cells and how much they can generate, near-field microscopy, surface-plasmon resonance microscopy (SPR), and lots of other very focused research (no pun intended, but ha haaa) into how light interacts when it’s squeezed into very, very tiny volumes.

Still not getting it?  Ok, from SPIE’s own journal on Nanophotonics, here’s a wide net on what the hell Nanophotonics covers:

  • Nanoparticles and nanoparticulate composite materials
  • Quantum dots and other low-dimensional nanostructures
  • Nanotubes, nanowires, and nanofibers
  • Nanowaveguides and nanoantennas
  • Sculptured thin films and nanostructured photonic crystals
  • Quantum optics and spintronics
  • Nanoscale optical electronics
  • Surface plasmons and nanoplasmonics
  • Ultrashort pulse propagation
  • Light-harvesting materials and devices
  • Nanophotonic detectors
  • Near-field optics
  • Optical manipulation techniques, spectroscopies, and scattering techniques
  • Molecular self-assembly, and other nanofabrication techniques
  • Nanobiophotonics
  • Nanophotonic concepts and systems that facilitate continued integration of various optical and/or electronic functions
  • Dynamically tunable, multifunctional, and/or active nanomaterials and metamaterials

Yeah, I looked up seven of them myself!


Regardless, it’s photonics and optics, and that is one of my favorite research locations!  Here’s Professor Kent Choquette at the University of Illinois at Champaign/Urbana talking nanophotonics to a group of students.  WARNING, NON-NERDS:  This is over an hour, and not for the feeble math minded!

Rube Goldberg Machine of Light


Dear Japanese marketing company who invented this video, that advertises a high-speed internet company called au Hikari:
I love you all so very much.


This whole video starts from one single beam of light — every piece of the Rube Goldberg machine is powered either in part or en toto by that one beam.

Thanks, Colossal!

Good Morning Inspiration – 100 Black Balloons vs. 1 Blu-Ray Laser

What is better than coherent light obliterating 100 very carefully placed balloons down a hallway complete with different angles and audio that is not related to sex?

This is something that I submit to THAT list:

Wanna make one of these lil’ experiments on your own?
Go get yourself a Blu-Ray laser, some black balloons, and do it!


Buon Venerdì! 

Feliz Viernes! 

Gëzuar e premte! 

Fericit Vineri! 




Meet ADAM: A Laser System that Protects Our Troops from Bad Guy Missiles


I can’t get over how crazy the development of military laser technology has been lately.  There’s been a real push to create a competitor for projectile weapons.  For example, earlier this week I talked about the new German Phalanx-style laser weapon that kills drones and little metal balls from the sky.  At one time before it was abandoned, the US Air Force was working on something called the YAL-1, which was a 747 mounted with a chemical laser that was designed to kill nuclear ICBMs from a long, long distance.  I thought it was actually pretty cool, but I can understand why it was scrapped; my assumption is that they’re holding out for a more multi-burst solid state laser instead of a single-shot, highly dangerous chemical laser.


I have to say that at one point in my life I was pretty frustrated that more money goes into military laser tech than goes into scientific research and development, or even medical laser development.  However, what I realized was that as this technology becomes more readily available via all of this defense money solving big problems up front, less than death uses and systems will “come out in the wash,” as an old colleague usually says.  Just like anything else that we steal from military technology (cable bundling, for example), at some point laser technology from military development will make its way to the civilian and private sector development.

One such system is something that Lockheed Martin calls ADAMArea Defense Anti-Munitions.  This system is designed to be towed into a hostile area where the US has set up a Forward Operating Base, or FOB, in enemy territory.  While our guys sleep and stand guard and all of those things, ADAM is watching over the area, blanketing it with radar that’s watching out for munitions coming into the area from enemy forces — mortar shells, shoulder-fired missiles, etcetera — and destroys the incoming round with a laser.  Check this out, this is a prototype test of a rocket being fired at the ADAM:

Ok, that is insane.  So right now, a system exists that can detect incoming enemy rockets and shells to a base.  Can you imagine what would happen if you were to deploy a handful of these systems across a battlefield?  That sounds like it would be a pretty awesome sight.  From a press release at Lockheed Martin’s website, they’ve also tested the ADAM against drones (UAVs, or Unmanned Aerial Vehicles) and small caliber shells:

Since August, the ADAM system has successfully engaged an unmanned aerial system target in flight at a range of approximately 1.5 kilometers (0.9 miles) and has destroyed four small-caliber rocket targets in simulated flight at a range of approximately 2 kilometers (1.2 miles).

“Lockheed Martin has invested in the development of the ADAM system because of the enormous potential effectiveness of high-energy lasers,” said Doug Graham, Lockheed Martin’s vice president of advanced programs for Strategic and Missile Defense Systems. “We are committed to supporting the transition of directed energy’s revolutionary capability to the war fighter.”

Designed for short-range defense of high-value areas including forward operating bases, the ADAM system’s 10-kilowatt fiber laser is engineered to destroy targets up to 2 kilometers (1.2 miles) away. The system precisely tracks targets in cluttered optical environments and has a tracking range of more than 5 kilometers (3.1 miles). The system has been designed to be flexible enough to operate against rockets as a standalone system and to engage unmanned aerial systems with an external radar cue. The ADAM system’s modular architecture combines commercial hardware components with the company’s proprietary software in an integrated and easy-to-operate system.

Here’s a video of the test they’re talking about, where ADAM shoots down a drone:

I for one am pretty excited to see what happens next.  This could lead to some amazing advancements in light.


Thanks Business Insider, Army Recognition!


When you see Eric Standley’s work, there are some things you must remember:

  1. Yes, these things really exist;
  2. It took Eric Standley a long, long time to make them;
  3. they are multiple layer, multi-dimensional laser cut pieces.

Now that we’re over that, check this out:


Eric Standley apparently has lots of Islamic, Gothic, and almost Buddhist inspiration in these pieces, or at least that’s what the artist wants us to think:






Laser cutting, supreme style.  I think that’s like Animal Style, but with more awesome.  Check out other of Eric Standley’s works at his website, there are lots of wonderful pieces there!

Thanks, 50 Watt!

Germany Developing Laser Armed Drones for Farming and Weed Killing


As unfunny as a subject this is, this is a really ironic story, too.  Right now, the scientists and researchers at the Leibniz University and a laser center in Hanover are currently working on an alternative to herbicides (and I assume pesticides?) that comes in a very strange form as they see it:  a drone equipped with a CO2 laser system.  I mean, this is no YAL-1 or anything, but still — using light to kill weeds!


This is an awesome idea, right?  A laser equipped drone, complete with some sort of artificial intelligence (AI) that allows it to distinguish good plants from bad species.  There is a lot of interest in this in Germany as well; in an article at DW:

Another possibility is drones, or small robotic planes that would fly over the fields. These could also fight weeds near protected waters, where herbicides are not allowed to be used. According to Marx, the German railway service has expressed interest in the project as well.

“30 percent of the railway tracks are in water protection areas where you can’t use herbicides anyway.”

Crazy.  So the Germans are working on a flying weed death machine that incorporates a limited-fire carbon dioxide laser and has intelligence on board that will allow it to distinguish between different types of pests or pest plant species and eliminate them using the on-board laser.  Trials for this machine are currently at least five years out, according to the article at DW.

Along with a host of other ethics and scare-tactic behaviors that will rival the anti-Obama ads on Facebook, there is a main issue here that people will whine over — and I mean such loud whining that it has the potential to change the physical properties of things, like a microwave oven:

If we let drones fly around, aren’t they going to float around and kill our children?!?!

Look — I know it, you know it, George W. Bush and Obama know it, and Fox News knows it:  Drones programmed for weed killing are not going to drive around with abandon slaughtering families and killing schoolchildren.  BUT:  like anything else, there will be accidents that are the cause of human error, and the religious Right will call the accidents “an act of God.”  However, does this happen every time a combine kills a cousin?  No.  But somehow the Devil will get inside of the machines, or perhaps even the machines developed their own intelligence and chose to slaughter innocent men, women, children, and other sentient beings.  It’s maddening what happens when people start slinging scare speak.

Let’s look on the This is AWESOME side of “robot weed wackers,” because frankly these types of technological advances are going to take place.  You will also notice that drones and lasers are going to be added to replace humans in a variety of different working environments; perhaps maybe the most expensive and dangerous gigs will see robots doing more of that work themselves, or assisted/controlled by a human handler.  I’m pretty sure that we’ll also see them first in very small, very specialized applications, and not out there replacing the teams of men and women who labor to do these jobs currently.  This is the one thing that we as humans will always fight no matter what —  we are afraid of anything that takes away a job from a human.  I think what we forget is that robotics and automation don’t take jobs away, they remove the need for a human being to do something menial and exhausting so that the human can go do something more important, like think of more things for which robotics can provide a solution!

Let’s look at just a few advantages of an imagined Laser Drone Weed Eliminator – a specific and unique application also performed by humans:

  • $$$ Savings on LABOR! 
    Sorry folks, it’s a fact of life.  Labor is expensive, increasingly and constantly, and is often the biggest expense that companies have to incur.  If a company that manufactures fixtures, for example, could double their profit by going completely automated in their manufacturing division, believe me that they would do it.  There will more than likely be the need for human tenders and maintenance workers for the robots, so we can presume that there will always be human tasks.
  • $$$ Savings on TIME
    Perhaps JUST as important as money, time is often money, and an automated drone-based device could do the same job every time, regardless of the kind of day the robot is having.  You could also work a robot a solid 24 hour day and never have to bill overtime.
  • Human Safety Factor
    There will be situations where a robot weed wacker will be the better worker for the task.  Case-in-point, clearing out old Juniper trees or weeding thick rose beds.  On a more extreme (and probably more realistic) scenario, think about something like weeding delicate flower beds or hydroponic setups where human interaction is the worst thing for the species.  These are all valid examples that exist in the industries today; both articles I found on this mention having the drone start in a small greenhouse environment or small farm.
  • Transition Time Between Workers
    As with any job, when one worker leaves a job and another takes his or her place, there is a considerable amount of time that will need to be spent bringing the new worker “to speed,” per se.  With a robot worker, presumably we could replace one for another, transfer some logic, and off we go for another 20 hour shift at that worker’s maximum efficiency potential.

We must remember as well that as our population grows and the urgency for agriculture to keep up with demand, pesticides and herbicides will need to decrease in usage altogether.  This is yet another complicated problem that will take years of research and development to really make happen.  But, we’re taking the right steps.  Baby steps.  I’m sure that the politicians will stick their fat fingers into the Laser Weed Wacker pie as well, which will be even mire fun to write about!


The laser’s operation, from an article at Gizmag:

The LZH [meaning Laser Zentrum Hannover, or the University’s laser center] method is to stunt or kill the weeds in place using a laser. This isn’t a completely new approach. Scientists have been experimenting with weed-killing lasers for years, but early attempts revolved around using lasers to cut weed stems or to boil the weeds in their own juices. This wasn’t always effective and the laser needed a lot of power to get the job done. There was also the constant problem of how to tell the weeds from the crops so the right ones were zapped.

LZH took a different approach. The team, headed by Thomas Rath of the Institute of Biological Production Systems, used a low-powered CO2 laser to strategically heat the water in the weeds’ cells. Instead of slicing through the weeds or burning them, the LZH laser would only heat the weed cells enough to damage them and thus inhibit their growth. This is trickier than it sounds, because if too little power is used, it can turn the laser into a high-tech sunlamp that actually promotes weed growth. As Christian Marx, Research Fellow in the Department of Biosystems and Horticultural Engineering explains, “it has been shown that lasers operating with too little energy are more favorable to weed growth, causing the exact opposite of what we want.”

According to LZH, the team succeeded in locating the weeds’ growth centers and inhibiting them as well as adapting the method to different plants and plant heights. But the real hurdle was in finding a way to make the weed-killing laser practical by making sure it killed only the weeds and not the crops.

There you have it, folks.  A weed killer drone that kills plants with lasers.  A grand idea — let’s see where this one goes in the future!  I’m excited to see the progress!

Laser Tattoo Removal?! It’s Like A SKIN ERASER!

First — no, I’m never getting my tattoos removed, and yes, I plan on getting both sleeves!  A friend sent me a link, and boom — there was a dude getting his tattoos removed.  Take a moment and check this out, it is actually quite amazing:


This process of laser tattoo removal is called laser ablation, or even better — selective photothermolysis.  That’s certainly a five dollar word, isn’t it?  If you break it down it’s pretty simple:  photo means light, thermo means heat, and lysis means destruction.  So destruction using light and heat.  Can you dig it?  To put this into perspective of, say, the entertainment industry, laser ablation is used to make glass and/or metal gobos, and can be done with ridiculous precision.  Ridiculous.  Laser Ablation is something that typically uses a pulsed laser because of its high power; when something is laser ablated, the power and temperature is usually at such a magnitude that the material being removed is often plasma-fied or just vaporized altogether.

Wanna get really nerdy with me?  I also checked out a paper called Optimizing Outcomes of Laser Tattoo Removal, talking about different wavelengths and laser types.  Yes, it’s interesting!

Hey, did I mention that video above has a guy basically getting his tattoos erased?!

Thanks, LikeCool

LIDAR Helps Scientists Add Mass to Dinosaurs

…and all of it without having to use the strawberry milkshake protein powder that I got from Walmart.  That stuff was horrible!!!

One of my favorite laser publications,, posted this awesome article — dinosaur skeletons, LIDAR, and imagining the mass of dinosaurs when they were alive.  The article is pretty cool, check it out here.

From the article:

A team at the University of Manchester has developed a new method for doing so that shows promise, by applying a lidar scanning technique to one of the largest mounted dinosaur skeletons in the world. The findings are published in Biology Letters.

Starting from the principle that the best estimates of dinosaur mass come from a volumetric approach, whereby a model of the animal is created and its mass then calculated via its density, the team scanned a complete skeleton using a lidar scanner supplied by Z+F, specialists in laser scanning and data capture.

I had to know more about this LIDAR business — LIDAR means Light Detection and Ranging.  From the wikipedia:

In general there are two kinds of lidar detection schema: “incoherent” or direct energy detection (which is principally an amplitude measurement) and Coherent detection (which is best for doppler, or phase sensitive measurements). Coherent systems generally use Optical heterodyne detection which being more sensitive than direct detection allows them to operate a much lower power but at the expense of more complex transceiver requirements.

In both coherent and incoherent LIDAR, there are two types of pulse models: micropulse lidar systems and high energy systems. Micropulse systems have developed as a result of the ever increasing amount of computer power available combined with advances in laser technology. They use considerably less energy in the laser, typically on the order of one microjoule, and are often “eye-safe,” meaning they can be used without safety precautions. High-power systems are common in atmospheric research, where they are widely used for measuring many atmospheric parameters: the height, layering and densities of clouds, cloud particle properties (extinction coefficient, backscatter coefficient, depolarization), temperature, pressure, wind, humidity, trace gas concentration (ozone, methane, nitrous oxide, etc.).[1]

There are several major components to a LIDAR system:

  1. Laser — 600–1000 nm lasers are most common for non-scientific applications. They are inexpensive, but since they can be focused and easily absorbed by the eye, the maximum power is limited by the need to make them eye-safe. Eye-safety is often a requirement for most applications. A common alternative, 1550 nm lasers, are eye-safe at much higher power levels since this wavelength is not focused by the eye, but the detector technology is less advanced and so these wavelengths are generally used at longer ranges and lower accuracies. They are also used for military applications as 1550 nm is not visible in night vision goggles, unlike the shorter 1000 nm infrared laser. Airborne topographic mapping lidars generally use 1064 nm diode pumped YAG lasers, while bathymetric systems generally use 532 nm frequency doubled diode pumped YAG lasers because 532 nm penetrates water with much less attenuation than does 1064 nm. Laser settings include the laser repetition rate (which controls the data collection speed). Pulse length is generally an attribute of the laser cavity length, the number of passes required through the gain material (YAG, YLF, etc.), and Q-switch speed. Better target resolution is achieved with shorter pulses, provided the LIDAR receiver detectors and electronics have sufficient bandwidth.[1]
  2. Scanner and optics — How fast images can be developed is also affected by the speed at which they are scanned. There are several options to scan the azimuth and elevation, including dual oscillating plane mirrors, a combination with a polygon mirror, a dual axis scanner (see Laser scanning). Optic choices affect the angular resolution and range that can be detected. A hole mirror or a beam splitter are options to collect a return signal.
  3. Photodetector and receiver electronics — Two main photodetector technologies are used in lidars: solid state photodetectors, such as silicon avalanche photodiodes, or photomultipliers. The sensitivity of the receiver is another parameter that has to be balanced in a LIDAR design.
  4. Position and navigation systems — LIDAR sensors that are mounted on mobile platforms such as airplanes or satellites require instrumentation to determine the absolute position and orientation of the sensor. Such devices generally include a Global Positioning System receiver and an Inertial Measurement Unit (IMU).

This scanning technology is actually pretty widely used all over the place — along with terrestrial map data from suppliers, the GPS companies’ travel vans are mostly fitted with LIDAR scanners.  These scanners are actually pretty cool – the company listed in the article, Z+F UK, has some particularly interesting looking devices!  Also, Radiohead apparently used lots of LIDAR capture to film their House of Cards video.  Here’s a bit of them doing some scanning work:

Crazy.  Also, if you’re one of those nerds like me who likes to comb through the images and content on places like NOAA and see the output from satellites at the various observation stations, check out the LIDAR stuff at the USGS (US Geological Survey) website.