AT&T Archives: Principles of the Optical Maser

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This 1963 film shows how basic physical concepts are applied to make an optical maser oscillate. The optical maser is examined as a generator of electromagnetic energy in the optical range of frequencies, having many similar qualities to standard radio and microwave oscillators. The principal types of gas and solid-state optical masers are shown in the laboratory.
Dr. C. G. B. Garrett of Bell Laboratories (and his prominent British accent) presents the material, which also includes lab demonstrations and animation. The Optical maser is a phrase that means the same as Laser - or Light Amplification by Stimulated Emission of Radiation. A Laser is basically a Maser that works with photons in the light spectrum. There are optical and infrared masers, as profiled in the 1958 pioneering paper that introduced the concept to the world, written by Bell Labs scientists Charles H. Townes and Arthur L. Schawlow.
Dr. Garrett worked with Dr.s Townes and Schawlow, and is shown here with the latter.
Original audience: college students
Produced at Bell Laboratories
Footage courtesy of AT&T Archives and History Center, Warren, NJ

[@MariusKohsiek]

The ages when lasers were optical masers, megahertz were megacycles and capacitors were called condensors =) And a very good lecture about stimulated emission, too!

[@petercampi2840]

Lasers are not masers. Although masers and lasers work on the same principles (population inversion, coherence, and collimation), they have different applications. Both are still used, but you won't find a laser that does a maser's job just as you wouldn't find a maser doing laser work.

[@TM-cb2te]

The technical expertise and intellectual honesty of yesteryear....

[@marshallkimjongil9216]

Back to first principles.

[@theprof291166]

The presentation style is a welcome relief from the 'whats up guys' and 'woaaahhh' style we get today, I think.

[@thapthoptheep2076]

But how amazing would it be if at the end this dude just said - please don't forget to smash that like button....

[@theprof291166]

@@thapthoptheep2076 ha ha - yes maybe.

[@c0t0d0s7]

“And check out our merchandise! We have T-shirts that say ‘My MASER can beat up your vacuum tube.’”

[@Klaus293]

Concise, precise and expository. There is not a single bit of wasted verbiage.

[@Frisenette]

This guy is amazing. Almost too perfect. Robotic even. But then, still very endearing. Brilliant film in every way.

[@c0t0d0s7]

Plot twist: He was an android.

[@paulvarn4712]

The release of these series of tech films by Bell and others are a valuable reminder of our technical heritage and should be an inspiration to future engineers.

[@Wa-De]

By the way: This is by far the BEST instructional material I have ever encountered regarding the LASER (Light Amplification by Stimulated Emission of Radiation); a term that was modified from MASER (Microwave Amplification by Stimulated Emission of Radiation) a short time later. I wish that they would have had this clip shown in my engineering classes!

[@theprof291166]

Yes - he finally made me understand the principle properly.

[@LMacNeill]

Now all you need is some extremely clear glass fiber, and you can transmit these coherent light waves for extremely long distances. 🙂 So cool to see the grandfather of our current laser-based fiber-optic data systems. What a fantastic explanation of what happens on an atomic scale in our lasers today. And it's so amazing that -- only a bit more than a decade after the making of this film -- they were able to create laser emitters that were so small, and so cheap, they could be released to the public in consumer devices (Laser Disc players, and a few years after that, CD players). Fascinating!!

[@activelow9297]

Flawless mid-atlantic accent here... impressive!

[@Wa-De]

We shan't mock the man's rather regal accent for fear of quite dire consequences.

[@bombasticbuster9340]

QUITE!

[@greensombrero3641]

I concur

[@marctronixx]

Rather

[@arnoldrimmer8008]

I think it's called "BBC English".

[@WCM1945]

@@arnoldrimmer8008 Modified for AT&T use.

[@klipsch21]

Did someone force you to watch this; Why so much hate? Sure it may sound dry and boring to you, but it was research like this which lead to the development of technology that make our lives easier and more enjoyable.

[@zapazap]

Whom were you addressing?

[@edgertor]

sadly, Dr. Garrett passed away in 2017. however, i learned from his obit that he had been gay and with a partner for 56 years. I wish i had known that when i interviewed him in 2013! RIP Dr. Garrett, you charming man!

[@NimbleJack3]

All too often gay men in STEM fields stay in the closet, long after they took castration or prison off the books for the "crime of homosexuality". The secrecy becomes a part of you after decades of hiding. I've seen many obituaries for late engineers that casually mention "his husband" somewhere in the paragraphs.

[@ThunderAppeal]

@@NimbleJack3 Or maybe people dont obsess over this like you may think. No one gives a shit about a persons sexual orientation just like no one gives a shit that Dr. Salk the inventor of the polio vaccine was Jewish. People only cared that he made the vaccine. So I'll repeat again, NO ONE GIVES A SHIT ABOUT A PERSONS SEXUAL ORIENTATION!!

[@ThunderAppeal]

And if you knew that what difference would it have made?

[@NimbleJack3]

You sound "triggered", friend. Do you need a safe space from discussions about sexual orientation?

[@19761999]

@@ThunderAppeal Sir, you are so wrong. I recently had a conversation with an otherwise respectable lawyer who to me that he is very homophobic and not ashamed of it. He told me he despises all gays, including family members. The other guy in our conversation didn't say anything but he was nodding his head in agreement with my homophobic friend. I told a female coworker about the conversation and she told me that also hates gays (she used a derogatory slur). She said they are sick and disgusting. Society has come a long way but we're not there yet. I know it's a different subject but as a black man I remember a white guy told me that no one cares about skin color anymore. That's not true either.

[@bakasan9677]

1960's Sheldon Cooper: Fun with Flags... Fun with Masers...

[@tachikomakusanagi3744]

I wish I'd seen this at the start of my degree, things would have made a lot more sense. Just showing a beam with its cavity mode visible would have helped so much.

[@stevtaal5266]

His voice... is velvet...

[@michaelgonzalez9058]

The emission acts like a carnival mirror giving its reflection to the atom

[@michaelgonzalez9058]

Gold

[@michaelgonzalez9058]

Like having one small ear with an exact duplicate of the inner ear producing ambiounce

[@michaelgonzalez9058]

In the excess of the equipment is the answer measurement the residue

[@michaelgonzalez9058]

These colors can be also endeavored to light the body

[@Aspenlogic]

Fabulous!

[@kiev786]

Maser and Laser are same just frequency difference. Maser generate frequency below visual lights (microwave) and laser generate frequency of visual lights and beyond.

[@zapazap]

Yet the phrase 'infrared laser' is commonly used.

[@andrewdewar8159]

I tried to look up the presenter, C.G.B Garret, it says he worked with Walter Brattain at Bell laboratories

[@icywiener5421]

Inspiring.

[@michaelgonzalez9058]

On the level at phase

[@alau18]

Big bang circa 1963

[@jessstuart7495]

The negative temperature concept is based on the definition of change in entropy: ΔS = ∫(1/T)dQ Rearranging the definition of entropy, we can write an expression for temperature. T = ∂Q/ ∂S . By this definition, temperature is the ratio of change in heat energy (Q) to change in entropy (S). When there are more electrons in the excited state than the ground state (population inversion), adding more energy to the system by pumping more electrons into the higher energy state, will decrease the system entropy (system becomes more ordered). ∂Q is positive, and ∂S is negative, so the ratio (absolute temperature) is negative. IMHO, using the thermodynamic definition of entropy to define temperature and to describe the distribution of electron energy levels should only be used in systems that can be modeled with a Boltzmann distribution of electron energy levels, which would only allow for positive temperatures. Applying the definition to a non-Boltzmann distribution of energy levels, like in a pumped laser with a population inversion is a mathematical hack and does not have a solid physical interpretation.

[@09pawankumaryadaveee10]

This man is handsome really. Love from India.

[@michaelgonzalez9058]

So the graphite light is black light wich can be measured

[@onewhosubmits]

yo I wish that guy was my professor lol thanks for posting this

[@theprof291166]

If he was, you wouldn't get away with 'Yo' :-)

[@hughsonj]

14:08 this guy just casually throws out Heisenberg's Uncertainty Principle

[@johnmorgan4368]

The first few seconds of this video make me want to grow a goatee, wear a beret, and snap my fingers, man.

[@WCM1945]

Yes, the jazz didn't match the timbre of the presentation. I'll take the jazz.

[@michaelgonzalez9058]

Use an Amp it Is a solid

[@8800081]

Spontaneous emission 🤐

[@alguien3732]

optical maser = laser

[@jonhohensee3258]

When he talks with his arms crossed I feel like he is reprimanding me. (And I don't even know what I did wrong!)

[@Desterado]

Wave particle duality

[@Spacecookie-]

Would you need physics, or chemistry to study this, or is it a crombined field of study, requiring both?

[@anteconfig5391]

physics. I think you learn a little bit of physics in chemistry. But I think it's mainly quantum physics or electrodynamics. idk but I think maybe classical electrodynamics or classical electromagnetism would help more. But I think that what is happening here is based on a quantum effect. He talks about Hertzian dipoles at (6:29) I didn't know what that was so I looked it up and the link I clicked on told me to think about to spherical conductors, connected by a wire, with a net zero charge and where the length of the wire was so small compared to a wavelength of emitted radiation. I read that and I thought "Nothing can get that close" and then I remembered the two charged particles the electron and the nucleus are very close together and when an electron loses energy and drops down from a higher orbit it emits a photon. I'm teaching this stuff to myself though so I don't know if that helped, but I don't think chemistry will be very helpful. I could be wrong though. I got this Physical Chemistry and it talks about stuff like nuclear magnetic resonance...

[@slowneutron6163]

Wow, Benedict Cumberbatch was terrific in this.

[@andrewdewar8159]

Oh that made me laugh ! good one !

[@midnightmilo]

Anyone know what happened to Dr. Garrett? can't find any biographical information.

[@VideoNOLA]

Nokia owns at least one of his early patents patents.google.com/patent/US3215949

[@VideoNOLA]

In early October, 1962, Dr. Garrett spoke at an Engineers Symposium in North Carolina. The topic was his book, "Optical Maser".

[@VideoNOLA]

He was known among his colleagues as Geoffrey.

[@SheikhN-bible-syndrome]

But if light and sound are of the same nature it's just a light is it a much higher frequency and how does light travel through space? Because sound is oscillating pressure of atmosphere but there's no atmosphere in space?

[@Vincent_Sullivan]

What Dr. Garrett actually says is that light and RADIO WAVES are of the same nature. They are both electromagnetic radiation, just at different frequencies and neither of them requires a medium (such as air) to travel through a distance. As you noted Maya, sound is an oscillating pressure wave and it requires a medium to travel through as there has to be "something" to transmit the pressure. That medium may be air but it could also be some other substance. For example, sound travels very well through water at a speed much higher than its speed in air. Speed of sound in air is about 343 metres per second and in water about 1480 metres per second. In mild steel it is about 5960 metres per second. These speeds are all very slow compared to the speed of electromagnetic waves which is about 300,000,000 metres per second in air or a vacuum. In solid transparent mediums such as glass light will travel slower which gives rise to the phenomenon called refraction where the direction of the travel of light is bent. The amount of bend depends on the frequency of the light and this is how a prism is able to separate the different colours (frequencies) of light. Dr. Garrett is using some analogies with sound to try to explain certain aspects of the maser (in particular stimulated emission) but he does warn that because sound and electromagnetic radiation are very different things you cannot carry the analogy too far or it will cease to be accurate and cause confusion. I hope this helps your understanding...

[@anchorbait6662]

Is this just a lazer?

[@nccrawford]

Popular media would have you believe that this gentleman is the same species as Post Malone...

[@DSAK55]

this guy later with to MI6 to become "Q"

[@HoTrEtArDeDcHiXx]

I see

[@Zenodilodon]

Sadly light emitting antennas are still inconveniently small and we still wouldn't know how to drive them :P

[@nr7000000001]

quantum dots?

[@aresaurelian]

Dielectric Planck fractals.

[@zapazap]

Jazzy!

[@grimsnark4849]

7:02 That's what she said

[@GoSlash27]

25:10 I, too, lack the pumping intensity to make Ruby oscillate :(

[@thapthoptheep2076]

I've honerstly had my dreams narrated in this style, wake up with this voice repeating some calm, odd phrase "now firmly emberd the axe in the zombies cranium before advancing to the next level!"

[@SpartanONegative]

Laser beam eyes

[@ThunderAppeal]

Fire the Maser! Hmm, that may work.

[@quantumofspace1367]

Благодарю Вас за видео. Здравствуйте, интересно можете думать не по шаблону? Как воздух носит волны звука. Так и гравитационное поля носит волны света. Данные выводы возможно подтвердит экспериментально: 1. На поверхности земли, его гравитационным полем, сносим направлено скорость света в волокне у оптических угловых гироскопов которые, расположены симметрично на специальной платформе и движутся по кругу без угловой скорости. 2. Используя два равных источника твердотельных мазеров, установленных встречно на периметре диска и при помощи отражателей и интерферометра Майкельсона возможно построить опыт определяющий скорость на периметре диска если он вращается или скорость движения автомобиля в «ДОМИНИРУЮЩЕМ ГРАВИТАЦИОННОМ ПОЛЕ ЗЕМЛИ. Вопрос. Почему нельзя при помощи этих же инструментов также определить на Земли её скорость по периметру орбит? Скорость света константа - но в рамках доминирующего гравитационного поля; планеты, звезды, галактики, скопления галактик … . -

[@VidMasterZ]

Also known as a laser...

[@michaelgonzalez9058]

Strobe

[@michaelgonzalez9058]

Is better with a 60watt bulbdipole

[@michaelgonzalez9058]

An 0ptical major is the 0utcom of a bulb

[@michaelgonzalez9058]

Concave

[@daverobinson6110]

This guy is in fact a robot

[@greensombrero3641]

That's quite a frequency band. Well, so is led zeppelin.

[@cipndale]

You're no fun anymore.

[@greensombrero3641]

@@cipndale I'm still fun 2 yrs later. HI!

[@PinyonGear]

#MAUI STRONG

[@StringerNews1]

"A maser."

[@purplekoke]

There is a lot of neat videos in their archives but the narrator in this one makes this video by far the creepiest.

[@krcm1981]

25:06 lol

[@godfreecharlie]

I miss these older lecture type docudemonstrations. This is back when science was rarely called "evil" or "demonic" by crackpot Republican christyun conspiracy theory adherents. We were the science leaders in the world, and a science education was an important part of most school curriculums. Now reason, critical thinking are pushed aside for prayer classes and babble studies. We're not number 1 anymore! But we are nearing a state of theocracy, leading the world in christyun fanaticism, bordering on lunacy. Flat earth claims, antivaxxer falsehoods, whimsical prophecy, that's what we excel at in 2021.

[@johnmorgan4368]

The first documentary I've ever seen where it feels like the host is hostile towards me.

[@WCM1945]

Very cold and businesslike, to be sure. That was considered "proper" back then. Being human was a weakness to be exploited by lazy students.