History of X-rays

Discusses the discovery, development and basic physics of x-ray generation.

[@coralspringsanimalhospital7301]

Dr. Klioze, I'm a licensed X-ray and MRI tech, but I've been in the veterinary field for about 15 years. All my trainees that pass through radiology (which is basically all nurses who get hired here) have the pleasure of watching your video. Very informative and entertaining as well, thank you for taking the time doing this!

[@ArifGhostwriter]

[From the UK, March 2023] This has to be one of the most fantastic explainer & history of the X-ray videos out there. 👍🏽👍🏽

[@WhoFlungPoo2024]

Well, I'll be darned! After almost 72 years, I finally know what that motor sound is when I received X-Rays (having never had the courage to ask the X-Ray Tech). Watched the whole video and loved the history and the theory. Oh, and BTW. I remember the thrill of the foot X-Ray machine at Florsheim in the 50's and OKC. But now I wonder about its latent effects. Thanks for a great lesson!

[@LU-jz8ci]

We call it "rotating", which is done by pressing the exposure button only half the way, we do it often when we need to be quick to take the picture, since it takes some time (about half a second) to get it rotating, and the exposure can't start until the anode is spinning at full speed

[@sunniewillow]

People got cancer for sure

[@sunniewillow]

Waaaait. We were taught that the first xray was of Mrs Roentgens hand??!!

[@HansLiu23]

Thanks for uploading. Undergrad engineers could also benefit from watching this

[@mikefixac]

Dr. Klioze, how thoroughly I enjoyed this video. Thank you. What amazes me is how quickly his discovery spread around the world. It wasn't till the 80s the cause of peptic ulcers was a bacterium, not stress. The medical community tried to disregard the doctor who discovered this. Today I believe knowledge of something even more simple and basic is readily available but it's disregarded by both the medical community and the lay public. I won't say what it is, but it will be interesting to see how it plays out in the future. Again, thank you for this.

[@Yousif474]

Many thanks Dr. Klioze for this explanation and reach background.

[@canvey555]

I'm very grateful for this video, as someone that doesn't usually understand these kinds of things it explained tremendously well how everything worked in fine detail. Thank you so much for this Chris England, UK

[@TeslaExplorer]

Very well explained. Thank you for this video!

[@jimaanders7527]

I remember the x-ray machines in shoe stores back around 1950. They were really fascinating for a kid. During the early days of x-ray development there were terrible cases of overexposure. I heard that Thomas Edison refused to have an x-ray of himself because he knew a man who had been badly injured by overexposure.

[@lutzweb]

One of the BEST science educational video ever seen!!

[@srideepprasad]

Well presented - and well researched. Thanks for sharing.

[@jacknick7582]

thanks for the explanation. also i liked the addition of the little vocal noises in the background haha

[@drsameerparmar]

Dear Doctor Klioze, Excellent efforts and amazing movie. Today my concept of ho Kv and mAs works is clear.

[@josepheridu3322]

A decade old video that is still useful and informative.

[@anlisitskaya]

Absolutely Amazing video!! clearly explained and very interesting

[@Chadwickyboy]

That radiograph of the foot is more interesting than let on. That is the "shadowgraph" Nikola Tesla sent to Wilhelm Roentgen shortly after he went public with the xray discovery in 1896. Tesla had been pursuing and experimenting with xrays at the same time, but had developed it far enough to impress even Roentgen.

[@Sixalienasa]

I read in Röentgen's Biography that he first noticed in a closed drawer fotographic paper or plate that had been exposed. He wondered why, and finally discovered that it was the X-ray that were responsible for it.

[@subramaniamchandrasekar1397]

You could have added the double side coated x-ray film and the luminescent back plate placed below the film that glows for some time after the exposure is stopped. This greatly reduced the exposure time to safe values. Great video. Regards.

[@shivnathsinghyadav7226]

Thank you for posting these videos! I have watched this video and the CT video and found them most enlightening. I currently live in Germany and what is interested is that Mr. Röntgen has a verb also in his honor "ge-röntg-t" means to have an X-Ray done.

[@movax20h]

BTW. A first Nobel Prize in Physic was received by Wilhelm Röntgen in 1901, for his research on X-rays. Also, Röntgen also studing and finished his PhD at ETH Zurich, Switzerland. He also met his wife here. I live just 30 seconds from a street named after him, Röntgenstrasse, close to Limmatplatz, Zurich, and a Röntgenplatz (converted from X intersection in 1984, which was due to a local population opposition to make it a high traffic road, and the opposition was named X-ray square festival :D) , which I visit daily because it is so close to my favorite coffee shop and grocery shop. Unfortunately I don't know if he lived in some apartment / house close by, but it is a possibility. But not entire, as I think the region was mostly industrial in nature at the time, and had some railroad there.

[@darylSKYTZOwillis]

Excellent documentary. Thank you. 🤙🏼

[@passedhighschoolphysics6010]

Nice video. The book, "Naked to the Bone" goes into a lot more detail. Hard to believe we once X-Rayed pregnant women to see the pelvic bones. The exposure time was typically 8 hours. No mention of The Beatles? They had so much money they funded the development CAT scanners.

[@lisanalaplante1559]

Thank so much Dr Klioze for sharing.

[@debbauert5826]

Well done, Dr Klioze!

[@southpark405]

Very well explained. I understand it now!

[@lucasquactemok8841]

Awesome!!! Thank You so much for this video. As a second year X-Ray student I have watched this video more than once. I was stationed in Giebelstadt, Germany from 1999 - 2002 which is about 15km south of Wurzburg where Dr. Roentgen's lab is located. I wish I would have known that I would eventually become an X-Ray student. I would have stopped at the University in Wurzburg and taken the tour in person. I drove by the University countless times on the way to the hospital where my daughter was born and throughout my tour in Germany. Just knowing I was so close to the birth of my new profession will suffice for now. Thank You Dr. Klioze for this fine presentation!!!

[@numatamayo5636]

Amazing video ! very well done.

[@stsfoxfacel9171]

Great video!!

[@mj197012]

Wonderful job. As a retired radiologist I thought you did a great job. I would love to see more videos of the fantastic devices over the course of years. The best example that comes to mind are the complex motion tomography units in the 70s and 80s, such as the Phillips Polytome and CGR tomography units. They were the epitome of mechanical engineering marvels.

[@tsparker99]

I enjoyed your video. I have been designing X-ray tubes for over 20 years, everything from a 0.5 watt tube which is on the Perseverance Rover, to a 110 Kilowatt tube designed for cardiac stop motion studies. I would like to make one correction to your understanding of the X-ray physics. The angled target has a negligible effect on the production or direction of the X-rays created. The electrons interact with the anode material and the photons are generated essentially in a spherical globe of emission. Those emitted in the direction of the anode structure are mostly absorbed in the anode or target as we call them. The other hemisphere of emission leaves the surface in all directions and must be shielded except for the photons which are useful in the direction of the object you wish to illuminate. The beam is trimmed or collimated as needed so as to only allow the useful photons to escape the tube housing. The reason the target (anode) is angled goes back to your discussion of the erosion of the target by heating of the anode material. The heat generated during high power exposures is sufficient to melt any metal. When done on purpose, this is used for electron welding. In X-ray tubes we do not want to melt the anode, but we also want a small point source for the X-rays to improve the image quality. We cannot have a point source, because it would melt the anode, so we compromise and make a narrow long focal spot on a rotating anode to spread the heat over a much larger area, but we place the electron beam on a slanted surface and look at it along the edge. This makes the focal spot looks almost like a point, or at least a very small box when viewed at a shallow angle. So, the rotation and angle are all about spreading the heat out over a large area, so we don't melt the anode. Perhaps you will make an updated video at some point and you can make the correction then. If not, at least it is in the comments.

[@jmchez]

That first control panel in the museum is a steampunk / Frankenstein movie fan's dream!

[@dr.ollabaei2896]

Excellent presented video.

[@antongolovko1149]

Man, what a good video. I feel so pillaged just to watch it! :)

[@jasonandrewismail2029]

excellent video. fundamental to understand the current technology

[@usaspl7556]

Great explain about X-ray and Thank you 💕😊

[@mercedesdantas3106]

Happy u mentioned Rosalind Franklin

[@Theworldbehindme]

Thank you sir for wonderful information.

[@ricoparadiso]

Great video, very informative.

[@alinuri5750]

thanks Dr.Klioze it's amazing video and explanation

[@ajskilton]

absolutely brilliant, thank you.

[@zinebounzar2825]

Thanks you very much for your hard working you video is fantastic

[@borisrunakov1662]

Excellent!

[@nicolasuribestanko]

FANTASTIC! As you so expertly expounded, everyone wanted to fool around with Xray machines when they first came out -- including the daughters of Tsar Nicholas II, who fancied themselves as nurses and got their daddy to buy a machine and install it in their palace.

[@hrvojewaldenstein4909]

Very didactical video! Bravo!

[@cr1spii]

thanks this will help lots with my NHD day project

[@benababiodanso2885]

Great job🎉❤

[@syntheticelementvids]

Thank you the video was great

[@oprahwinfrey878]

That was excellent

[@leexavier44]

Lots of information... thank you..

[@wardogies]

Dr Klioze you should talk about the 3 different ways the x-ray image is captured on Flim,computed radiography and digital radiography

[@Ittybittythetwofacedkitty]

Good presentation! Thank you

[@NPC-bt3sp]

Great explanation!

[@ElectricExperimentsRobert33]

A panoramic radiograph the teeth is greater than or less than an x-ray for the chest? Thanks :)

[@wardogies]

Much less it’s a stationary anode much lower power

[@pilotavery]

Much much less

[@mayshack]

A standard chest xray is 0.1mSv of radiation, panoramic dental xrays are 0.025mSv, about 4 times less. A single shot of the chest is equivalent to 10 days of background radiation, panoramic dental xrays are equal to about 3 days of background radiation.

[@cosmicrozie]

this is helping me so much with my nhd project 😭😭😭

[@moraxella.catarrhalis]

Thank You So Much doctor!!!

[@Aliali-mk6jq]

Interesting work

[@YTUSER583]

Great explanation.

[@tonyisis1423]

excellent>>>!!!

[@user-lw5xw7op9n]

لوسمحتم المواضيع في غاية الروعة لكن تحتاج الى الترجمة ، ساعدونا

[@moraxella.catarrhalis]

Will there be a specific video about fluoroscopy?

[@drzubairniaz5547]

Made it simple and comprehensive,love from pakistan

[@bodgertime]

Thanks, Doc

[@noorstudent331]

It was awesome thanx😄

[@BigEpinstriping]

In regards to television CRT tubes, for the most part you're correct, but you neglect to account for the fact that Cathode Ray Tubes were made of leaded glass (Which is why CRT's are so heavy); This practically eliminates radiation exposure, not much higher than background radiation levels.

[@lbochtler]

To combat the XRay output of a CRT, at least with color CRT's, was to have the faceplate of the tube be made of thick lead glass. and in general the entire tube was made of lead glass if i recall. Early black and white tubes where less shielded and most definitely emitted X-Rays. Not fully sure if the relatively thin faced oscilloscope tubes also produce significant amount of xrays, ill have to check that. In general, in terms of shielding X-Rays up to the 125KV range, (about double the voltage used in large color CRT's) a roughly 1cm thick lead glass pain is enough to reduce the exposure down to basically harmless levels. Though this also depends on the beam current, and amount of lead in the glass. The leaded glass i am talking about has a yellow green tint to it, which is a rather bad thing for color CRT's, so lower levels of lead are used. I can write more about this if anyone is interested

[@adzijderlaan7070]

Great video. As I understood in English speaking countries they called it X Ray's where X stands for unknown. Mr Rontgen was a dutchman born in Apeldoorn. Now in the hospital where I was treated they just call them photons.

[@LU-jz8ci]

In Sweden, we call them röntgenstrålar, in english "röntgen rays"

[@Rezaulkarim-xf3st]

Thank you very much.

[@Zephlex]

Hello Doctor Klioze, would you mind if I asked where you got the animations from? For the cathode/anode evolution

[@DoctorKlioze]

+Zephlex I do 99% of 3D video animations. Those were done with an old program called Ray Dream Studio's. Fantastic consumer level animation package but, unfortunately, is no longer available. I'm not sure what's the best and easiest to use now but I've been dabbling in 3D-Studio Max. Excellent platform. Very versatile and produces fantastic 3D images. Because of all the available features, a little tough to master, however.

[@Zephlex]

+Doctor Klioze Thanks, i'm playing around with 3Ds max right now :). I've actually got another question, you mentioned that x-rays at the time took a long time to generate due to the inefficiency of the crook's tube. How does that tie in with Professor Rontgen being able to see the bones of his hand in the lab? Did he hold up his hand for 20 minutes?

[@DoctorKlioze]

+Zephlex In the lab, Roentgen simply saw the glowing phosphorescent plate near the Crookes tube and when he placed his hand between the tube and the plate, he thought he could see the bones of his hands. However, the image was very blurry with poor spatial and contrast resolution. That's why he wasn't actually sure what he was witnessing. Over the next 8 weeks, he worked out the details of his new ray and developed a technique for recording the phenomenon on a sheet of film for presentation purposes. With the inefficient Crookes tube and lack of a good phosphorescent screen (now standard on any film-screen cassette), the process required many minutes of exposure to produce an image with sufficient anatomic detail.

[@Zephlex]

+Doctor Klioze many thanks for the thorough explanation.

[@kantdrawl3328]

Bud Hinkle. Reminded me of Ray Finkle!

[@KhalidFarooq786]

superb

[@margaqrt]

This is a fantastic presentation and was very interesting. Thank you for uploading.

[@benparenonicolas5292]

How to combine vernacular night vision scope building x ray ?

[@getuliocavalcante5215]

very cool

[@elitokihaste]

Amazing

[@kaye3441]

Is that paper that glow is called fluorescent screen?

[@vishalbindlish6407]

Awesome

[@kakkarot045]

Thank you

[@richasinh]

It's really really helpful....just perfect. Thank you soooo much. God bless you!

[@dfgfhg]

Great documentary (although I would have liked if it explained how the images are created [what's going on when the x-rays impact the blank target image made of I don't know what]), thanks for making them.

[@DoctorKlioze]

With classic film-screen technology, the x-ray hits a screen coated with a fluorescent material. The x-ray is absorbed and the fluorescent chemical emits a small light with an intensity proportional to the energy of the original x-ray. This visible light then exposes a standard sheet of film which is subsequently developed into the x-ray image. Computed Radiography or CR uses the same fluorescent screen but the light is captured on a solid state matrix which stores the image in digital form which can then be read by the computer. Great question!

[@dfgfhg]

Thank you very much.

[@Drewm000-z7f]

So that image at 11:01 is actually the very first radiograph not the other one in the beginning of the video. Also that radiograph is of Roentgen's wife Bertha.

[@AlexiHolford]

the radiograph of Bertha's hand is not shown in this video. It can be seen in this video: kzbin.info/www/bejne/hoWqnqCfpbmdocU

[@donal-bertomaldonado3428]

I have a question, do regular light bulbs produce x-ray energy at a very low dosage?

[@DoctorKlioze]

No. The electrons are simply boiled off the heated filament but they aren't accelerated through the bulb and therefore, cannot produce x-rays.

[@DoctorKlioze]

Good question but no. The electrons on the heated element are not in a strong magnetic field so they don't accelerate through the bulb with enough force to produce x-rays (unlike the old TV tubes that did produce some low level x-rays)

[@vittoriobacchiega9118]

The accelerated electrons must hit a metal target (anode) to make onto this an energetic jump of internal (more energy) electrons orbit level forward another (external)orbit and when return to previous orbit release this high energy (secondary emission) kind radiation with short waves (high frequency).

[@diegooppo6830]

Very interesting, however, of its about rays coming from electricity, where does the harm come from ? I know the Radio was a new element discovered by Marie Curie, is there a connecting?

[@youcefdjedi5563]

Hello Doctor Luis Sorry for disturbing you for small business 4 x ray tube is given with different kind of antikatod (Mo,CU,Co,Cr) rank this 4 tube by the work performance based ont he thermal conductivity? Best Regards.

[@DoctorKlioze]

Youcef - I was an electrical engineer before going to medical school but, unfortunately, I don't know enough about materials engineering & science to answer your question confidently! From what I recall during my training, most of our current x-ray tubes for standard body and CT imaging have Tungsten anodes because of their durability under the harsh environment of a hot cathode ray tube and the fact that the characteristic x-rays emitted are in the perfect range for body imaging. On the other hand, breast imaging or mammography uses an x-ray tube with a Molybdenum anode to produce the softer, less energetic x-rays necessary for this type of diagnostic work. Good luck!

[@youcefdjedi5563]

thank you Doctor Klioze. Good luck!

[@estebanfuenzalida7581]

That guy that jumped on that car definetely died on camera

[@ArifGhostwriter]

But wait a minute - don't modern X-ray machines instead now use a radioactive source (as in, literal lump of radioactive material) - & the machine then operates a shutter, to control exposure time? Which is why X-ray machines have strict protocols around decommissioning & disposal.

[@slooh1991]

thanks

[@jmchez]

Most people leave out the contributions in this area and the very, very important photoelectric effect of Philip Lenard. Lenard has become an unperson because of his horrendous behavior in wholly and enthusiastically embracing the Nationalist Socialist German Workers Party, the Nazis. It was Lenard's development of a very high voltage Crooke's tube that helped Roentgen. In fact, Roentgen borrowed Lenard's tube for his experiments. Even more important was Lenard's amazing and very detailed photoelectric experiments, which provided such precise data that Einstein used to show that light behaved as wave packets of electromagnetic radiation, later to be called, photons. I mention this because I found it amazing that no Physics book would say who did the photoelectric experiment that gave Einstein his insight into the workings of light. It took me a long time to find out.

[@DoctorKlioze]

Very interesting! I didn’t know any of that myself. Thanks for sharing!

[@jmchez]

@@DoctorKlioze No problem. After learning about Lenard, I happened upon the "Kathy Loves Physics and History" KZbin Channel. In that channel, Kathy recounts stuff " You never learned in school". Her videos are really good in going step by step (and I really mean step by step) on the history of electricity and technological developments. I find them very informative and entertaining, just like your video. kzbin.infofeatured

[@DoctorKlioze]

jmchez 👊🙏

[@pa4tim]

at 10:46 is that Thomson on the right ? I read he was not there in 1895 so it could not be him (and long white beards where not uncommon back then) He supposed to had his hand Xrayed (by Rontgen ? ) in 1896. If it is lord Kelvin then this picture is from 1896. I'm interested in Xray for electronics trouble shooting not in medical stuff but I do like your video.

[@DoctorKlioze]

I assume you are referring to Sir JJ Thomson, credited with the discovery of the electron. Great question but I doubt it's him. This scene took place in Wurzburg Germany in 1895 and, while professor Thomson was alive during that time, being an Englishman, almost certainly was not in attendance at Roentgens initial presentation.

[@pa4tim]

No, not JJ but William Thomson, aka Lord Kelvin ( degrees Kelvin is named after him). I have read his biography because he also did a lot for my field of interest, electronic measurements. He invented f.i. the electrometer, but he did a lot more. From math to thermodynamics, telegraph over sea, etc. en.wikipedia.org/wiki/William_Thomson,_1st_Baron_Kelvin Kelvin was indeed not there at Roentgens initial presentation. If I remember well, he was invited but did not believe Rontgen. He had contact after the presentation with rontgen who sended him information. A year later they met and Thomson had his hand Xrayed by rontgen. Thomson had contact with most of the great minds in that area and traveled "often" to the mainland.

[@stevenking2980]

Like the video. I think I'll subscribe. Thanks sir.

[@xray_prof]

X-rays cannot be redirected or focused. When any x-ray tube emits radiation the radiation propagates in every direction. The angle of the anode is there to control the size of the effective focal spot not direct the rays. Otherwise an excellent video.

[@garyhiggins5823]

One thing that you skipped is that taking an X-ray is done in two stages. Stage one, the rotating anode builds up speed while the (positive) element heats up. The anode is not negatively charged during this stage. No xrays are being created at this point. During stage two, the anode receives its negative charge in a timed manner. For a chest xray, it took around of 1/100th of a second. Positive ions slam onto the very briefly negatively charged anode, and boom, the magic happens. I spent a lot of time explaining to radiation paranoid people that the only time any xrays actually happened in the room were when my finger was pushing the stage two button and that the exposure was controlled by electronics. By the time you hear the beep, the exposure is long since finished.

[@DoctorKlioze]

You're correct that, in a modern tube, x-ray production is staged as you described. However you're incorrect regarding tube polarity. At the moment of x-ray production, the rotating anode is positively charged and the heated cathode element is negatively charged.

[@garyhiggins5823]

@@DoctorKlioze I must have gotten my polarity reversed after 30 years of taking x-rays...you're right, my bad!

[@johnkerley4152]

How much of a vacuum is typical for an X-ray tube?

[@rorycraig]

A complete vacuum must be applied to the tube for an efficient x ray. Most modern x ray tubes are completely deprived of air.

[@ShevillMathers]

Always interesting to see these presentations of the early discoveries and just how crude their ‘tools’ were. I am not being picky in my comments but would like to correct a point. Just a note from a medical scientist who in his much younger days, recreated many experiments based on those early ‘electrical’ devices and vacuum tubes, etc. I actually obtained a used X-Ray anode like that shown in the diagram, that angle is 45 degrees, which means that the electron beam is reflected at 90 degrees, straight down, not at the angle shown in this presentation. The angle of reflection equals the angle of incidence, a fixed law of physics.

[@OGRH]

Someone correct me if I’m wrong because I stopped at 152... please don’t tell me this guy glossed over the fact that the first x-ray machines were used two treat women’s skin to improve beauty and ended up having horrifying consequences. Not to mention the fact the exposure to radiation was off the charts from these early machines.

[@johno9507]

I have a pile of X-rays more than 4 inches thick and hold the unfortunate honour of having my hospital file labelled 'Do not X-ray' as after more than 30 major operations I've exceeded my safe lifetime dose of X-rays.

[@xxheart_breakerxx8732]

I injured both of my ankles yesterday. Had you seen the accident, you'd sure as hell x-ray my ankles (and we had it on video, so I was able to show the doctor), but the dumb guy who did the x-ray questioned why I would X-ray both of my ankles when I was able to walk and that it’s so dangerous and that it wasn’t necessary at all. The look on his face when he saw the X-ray pictures of my ankles tho…

[@RynaxAlien]

Nicola Tesla might have been inventor of Xrays and like many other technologies

[@RynaxAlien]

@Julez O'Neil If Tesla lab didn't burn it would have been otherwise. Tesla is genius not of his time.

[@movax20h]

Isn't mAs, just mC (milli Columb)? A product of current and time, to tell how many charges were transfered between electrods. Ampere by definition (originally) is Columb per second.

[@DoctorKlioze]

It's been a while since my electrical engineering days but I think coulomb is simply the magnitude of the charge and ampere is the amount of flowing charge. So if the time is fixed (as it would be in this situation), I would say you are correct with regards to the flow through the heated cathode. They would be equivalent. Anybody else?

[@michaelgonzalez9058]

Take a car and exercise an e,x ray of its fuel and distinguish the fuel 3xamination of the fuel and u will solve the consumption of the car

[@hojo70]

Today we look back at how dangerously X-rays were used 50 years ago and are shocked and appalled how carelessly humans were exposed. People alive 50 years from now will look back on 2021 and will do the same. It's hard to believe X-rays are used for non-emergency uses today.

[@oliverjudson1834]

they are safe an sdont make that much radiation

[@jadumonigogoi845]

nice video .but how much harm done by old tv ray to body?

[@DoctorKlioze]

Fortunately, the strength of x-rays and gamma rays drop off proportionally to the square of the distance from the source. So, as long as you didn't have your face right on the screen, you were probably OK.

[@anullhandle]

TVs emitted very little xray when working properly. Iirc color tv used leaded glass faces. They did emit some xrays off axis but their 30kv soft ish xrays could clime to higher energies as components degraded and voltage climbed. Not even close to the shoe machines or continuous emission imaging machines.

[@x2malandy]

He noticed the glow and then he noticed the candy bar in his shirt pocket had melted. Ha