Raspberry Pi 4 CRT-based VR Headset

What would virtual reality be like if flat panel display technology were never invented? In this project, Andy uses a pair of CRTs and the Raspberry Pi 4 to build a VR headset with stereoscopic 3D, 3DOF head tracking, and custom, browser-based software. It may not be practical but it's definitely unique and guaranteed to have no screen door effect: bit.ly/2QCoKjg
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[@tetsujin_144]

Now you have the perfect setup to run all those classic Virtual Boy games

[@RobertTheHaunter]

Tetsujin this comment is cursed

[@jmalmsten]

Having run Virtual Boy emulators on both the Rift CV1 and Quest, I can say that with proper head tracking the games are surprisingly playable. Of course the CRT setup would be more tech accurate but if people a curious about the platform I'd highly recommend trying it out since emulators exist and run fairly well.

[@MsHojat]

Virtual Boy didn't use a CRT. It used a a 1 pixel by 186(?) pixel monochromatic LED (or LCD?) strip, and then a quickly moving mirror to multiply that one pixel into the capability to display more via strobing/duty-cycle (like when you hook up LEDs to a fan or fast spinning stick, if you've seen that in action) It's one of the few reasons why it was not only completely terrible, but couldn't even be called VR (which is why it's so annoying when people scoff at VR by mentioning Virtual Boy)

[@SockyNoob]

@@jmalmsten run it in black and white though since the red is gonna give you a migraine fast.

[@supernovagamer929]

@@MsHojat The single row of pixels also has a weird effect of having a high frame rate and no ghosting, and if you play a virtual boy now they are surprisingly smooth and sharp

[@LetustheDragon]

1990: Don't sit too close to that (CR)TV, you'll damage your eyes! 2020:

[@Nightspyz1]

this!

[@Bleats_Sinodai]

That's half misinformation caused by a few cases of radiation poisoning that happened when the VERY first TVs came out. It was ONE brand of TVs that did it, because they forgot to add a protective layer in the glass. No other CRTs since then have caused issues. The "damage" is natural eye strain for staring at a screen for hours, which people still get today with modern display technologies.

[@GoldSrc_]

@Zwenk Wiel CRT glass has lead in it which is why it's really good at blocking X-rays, and also viewfinder CRTs don't use that high of a voltage, so the chances of you receiving X-rays from any of them is quite low. It is only when the CRT has a malfunction and the high voltage goes too high, that you start producing X-rays. But normally you're safe.

[@badreality2]

@Zwenk Wiel ...and computer monitors.

[@fadammte_aggst]

@@GoldSrc_ "It is only when the CRT has a malfunction and the high voltage goes too high, that you start producing X-rays." Asking for a friend (of course): Could one make an xray machine out of a 'malfunctioning' CRT with high voltage (that goes too high)?

[@joemieszczur9735]

GENIUS! when i was a kid i was grounded and my mom took my tv. i ended up using an old broken VHS camcorder to play my PS1 using the viewfinder. tiny crt's are the best.

[@RetroPlus]

Desperate times call for desperate measures

[@nexxusty]

Are you serious? Hahahah, that is awesome.

[@thebricktop]

augmented ps1

[@EvenTheDogAgrees]

Creative solution. :)

[@WednesdayMan]

uh, VR Tech did start in the PS1 era, remember the Virtual Boy? yeah that didn't work so well.

[@BenHeckHacks]

Wow that was awesome!

[@shaneneyome]

Ur turn. Make a vr headset lol. I miss ur videos.

[@andywest5773]

Thanks, Ben. Your show inspired me to try building things like this.

[@sqliffty5ive]

The fact a guy makes both a headset and the software demo is really inspiring. Good job man !

[@PixelisedPaul]

"We've got our screens, we've got our head tracking hardware. We're wired and running to go except for one problem; how do we turn this into an actual headset? Normally I'd turn to 3D printing to create our parts, but I don't think this is the best fit for this project" Answer: hot glue everything to your face.

[@IgorKolar]

@@silvervens there are 'cold temperature' hot glues! Just...50ish C or so :D

[@lokasz9]

When I heard about screen door effect I thought: "wouldn't CRTs fix this?"

[@SwishaMane420]

LOL

[@TheCobrabee]

bug vision with the tricolor filters

[@runrundave]

Exactly. They can make new crts that small and we be in business

[@Thats_Cool_Jack]

also zero screen tearing

[@batt3ryac1d]

also just higher resolutions lol. It's not really that big a problem anyway I always just tune it out and only notice it when I try to. My vive is so immersive if it wasn't for the cables I'd forget it was on.

[@jameslangridge8849]

i'd love to see this integrated with steam VR somehow, although i can't imagine how!

[@foldionepapyrus3441]

Looking around the available documentation quickly seems like openvr from Valve available on github would let you do just this. I've just browsed the top to see it is supposed to be possible (as i'm working on a Project Northstar AR/VR helmet and wanted the integration eventually - though when this project will actually get the deskspace to work on I don't know, and till the hardware works not much point digging deeper into the software)

[@tyler.r]

@@foldionepapyrus3441 To be honest at this point I would take a look at OpenXR apparently there is a "device plugin interface"

[@foldionepapyrus3441]

@@tyler.r Hmm I'd not heard of that one. Thanks I will have a look myself (when I get to this project)

[@PippyLive]

it would be interesting although very limited as this headset is 3DOF and steamvr is mostly 6DOF

[@foldionepapyrus3441]

@@PippyLive Could always attacth a vive tracker to it if you want the too.

[@GoldSrc_]

It never occurred to me to use viewfinder CRTs for something like this, and I've know about them for a long time. Amazing.

[@LowFlatRate]

"I'll just throw together these random assets for a demo..." :accidentally recreates scene from the Radiohead - Motion Picture Soundtrack music video

[@Razumen]

Sounds like the music video wasn't that impressive.

[@SurajGrewal]

Could have flipped the scanning coil wires instead of software based rotation. I did it for my CRT tube based active night vision

[@andywest5773]

Very true. If it wasn't so easy to flip in software I might have done that.

[@SurajGrewal]

@@andywest5773 lol, we do have different standards of ease,I guess 🤣

[@smithincanton]

>CRT tube based active night vision I had a similar idea using CRT tube view finders! Would love to see some details about this!

[@SurajGrewal]

@@smithincanton just a security camera hooked onto a camera viewfinder and ir light, packed inside a PVC tube which was originally ment for plumbing. Turns out, buying a proper gen 2 tube off of an old BTR costs the same (40$)

[@ryanfakename251]

How difficult/'expensive was that to make? I am an airsoft enthusiast and that sounds interesting for night combat

[@chrislaws4785]

Talk about nostalgia, when you opened that first cameras case. My dad had that EXACT camera back around 1993-96. I have many a fond memories of me dad using it to record family Christmas get to gathers, Christmas mornings and birthday parties. I think he even still actually has the thing and in complete WORKING order as well. It's crazy to think that in less then 10 years cameras went from literally being the size of a suit case to small enough to fit in your pocket.

[@PMVault]

Not even close to obsolete, CRT has nearly perfect scaling and frame rate sync.

[@zulc22]

CRTs are obsolete by literal definition. they are no longer produced. this isn't to say there's *nothing that makes them better*, i like CRT displays plenty. scaling depends HEAVILY on dot pitch though

[@zulc22]

low dot-pitch consumer television sets do things like blur together genesis-style dithers, adding something to the image by removing some quality. on most cheap CRT TV sets the scanlines from 240p are visible, but the phosphor isn't dense enough to really capture that detail when you zoom in or take a photo; you kind of just have to switch from 480i to 240p to really see it

[@zulc22]

but then a high dotpitch CRT; low-res scaling is beautiful, but native res...? is just about comparable to an OLED or something

[@fureversalty]

Me: Mom can we get a VR headset? Mom: No we have a vr headset at home VR headset at home:

[@manecronik]

ha ha funny funny

[@FPSRayn]

ha ha funny funny

[@CaveyMoth]

ha ha funny funny

[@maniacatthecontrols]

Wow. Possibly the best project I've ever seen.

[@TimothyTimPSP]

This guy sounds like a friendly robot.

[@StellarMoig]

I really like his voice. Very radio/commercial

[@keahibailey2646]

Pathfinder from apex Legends

[@MaxJ.ProfessionalLilGuy]

He sounds like he’s about to tell me the rules of the Fitness Gram Pacer Test

[@m4nuz]

@Alex Frideres oh shit... it will going to terminate you, still with this voice :O

[@bitluni]

That's awsome! I need to rebuild it with the esp32

[@MAYERMAKES]

That was to be expected!

[@enzofrancesca]

Please do it! It would be awesome...

[@KodakYarr]

Is the ESP32 powerful enough for that?

[@BraveRock]

That’s incredible! So much work! I had no idea that those old cameras used CRTs

[@XatxiFly]

Absolutely delightful project and also thanks for the warning about CRTs, I had no idea!

[@pizzalicker4576]

I tried to do this very same project back in the 1990's. I failed, but always felt like it was something that needed to and, could be done. I wish the Pi existed back then. Good work and thank you for breaching (and dealing with) the subject of software interaction complexities.

[@Rubbe87]

I did try it in the 90s successfully.

[@Vanillaessence]

This is so good and imo this video alone is enough to justify this channel continuing. Great stuff!

[@dpc4548]

Crts aren't quite obsolete yet. We use them in our editing bay as a colour checker for accurate colours. I still have 2 at home for this reason. They're a great professional tool!

[@beesong2729]

me: hey mom can we get valve index mom: we have valve index at home the valve index at home:

[@sabinsx]

underrated comment.

[@simpson6700]

me: hey mom can we get original jokes mom: we have original jokes at home the original jokes at home:

[@generic_programmer]

@@simpson6700 me: hey mom, can we get original replies to unoriginal comments on youtube? Mom: we have those replies at home. Replies at home:

[@mincrmatt12]

I wonder what it would look like with a vector CRT (or maybe one of those weird hybrid LCD-CRTs that did color vectors)

[@mcrsit]

This Andy is quite entertaining to watch. I'll definately come back to more of his videos!

[@cvspvr]

yes, this andy is a lot more entertaining to watch than other andies

[@alexandergranados1718]

I love the design of this! Super retro futuristic!

[@mileskosik472]

Thank you for using broken camcorders and not destroying good vintage electronics like nearly every other KZbin channel would do.

[@katiereeves1537]

thought about doing this a couple years ago but honestly would never get around to it, glad see it actually done

[@KnightMD]

I love you man. This is awesome. Thank you for the project but also for the lovely film making, script and editing.

[@Theodore-ox6no]

when you want to play HalfLife-Alex but you cant afford a headset

[@bradcobalt]

Or your tired of waiting for the Valve Index to be off back order!

[@CaveyMoth]

All of this probably costs more than a Lenovo Explorer, actually.

[@nasimagdam2723]

@@bradcobalt you can order it now

[@benjibat4655]

As happy as i am to see this, I'm frustrated because I've had this idea for a few years but haven't been able to get my CRTs working right.

[@apollion888]

Dude! Outstanding work. I haven't coded in 10 years and really enjoyed this trip

[@Kumimono]

Absolute madness. Keep it up. :) I wonder if those old Virtuality arcade VR machines used something similar to those CRT's... A sidenote, that camera chassis would be a great base for a sci-fi kitbash blaster thingy.

[@allenlewis5689]

Still has a better field of view than anything else on the market.

[@Roushyy_]

Actually baffled that I just now found this channel... awesome content.

[@Lapha002]

I can imagine that when vr becomes competitive, there are those who would want a crt-based headset only because of the nearly zero input lag and lack of motion bluring

[@RobertMorgan]

What type of optics do they use in those Fat Shark POV goggles for Drone Racing League, where they're flying drones at ludicrous speed through complicated courses? I'd guess those have extremely low latency, lag, and blurring

[@melissa6470]

@@RobertMorgan I'm inclined to think they're just LCDs.

[@ChrisD__]

@@melissa6470 Some of the newer ones are micro-OLED

[@turkeycannon161]

3:34 "Let's remove this ICUP..." You're not getting me this time!

[@CaveyMoth]

Next step: Harvesting the two cameras from the old camcorders, and adding them onto the headset to create inside-out tracking. 6 degrees of freedom, baby!

[@geronimowilliamson2173]

Thanks for helping me to understand the value of recycling old parts with raspberry pi.

[@utubby3730]

First time viewer. Wow this was really neat. I can just imagine the work that went in off camera!

[@soul-6323]

you shouldnt have used the hdmi to av converter they introduce tons of lag

[@mcshaggyswildadventures3952]

Yeah, theres literally composite through the 3.5mm jack

[@AmeshaSpentaArmaiti]

@@mcshaggyswildadventures3952 I didn't know this, cool.

[@soul-6323]

exactly,i knwo that the zerio has a dedicated composite pin but im not sure if its on all models

[@midgetman4206]

Seeing stuff like this confuses me, oh well I a can at least find comfort in (usually) understanding the mechanical side of technology

[@menotu000]

Since we now have access to quantum technology, mini engines, etc... I wonder if we could use some of that miniaturization tech to make new color CRTs that are HD AND small. I think that would be an interesting project. Imagine a 1" color CRT with full HD capable, but without the drawback or LDC/OLED screens (namely display lag)... run on an SVideo signal or similar.

[@badreality2]

CRTs can receive a digital signal HDMI/DVI, etc, as long as their internal circuitry allows it. They are not limited to analog signals. There was a developing flat-panel technology conceived around 2010, that was called sed, then fed. It used an-array of small crts like the ones featured in this video, to illuminate a flat-panel display. It was Full HD, and all of the benefits of crts. ...then flat-panel makers made the decision for consumers, to not develop this technology, and it was almost forgotten. Plasma flat-panel technology, the screen technology that everybody said reminded them of crt screen technology, suffered the same fate in 2013. 😞

[@zcubedmusic]

this was an awesome project. I was especially interested in the bit where you connect the accelerometer. I wonder if you have any ideas on DIY conversion kits for 3DOF -> 6DOF head tracking or even custom 6DOF VR controllers?

[@relativityboy]

"That's all we have for today" - all you have is SUPER AWESOME! WOOT! GREAT WORK!

[@slicedpage]

I think this design is better than a few of today's headsets. Removing any resting on the nose is a great step forward.

[@CecilMerrell]

For the web browser you can use the web browser sample code in qt. You can code it to a set url and run it borderless at a fixed window position and size.

[@jaymesyt]

This is SUPER retro-futuristic i love it

[@Jdbye]

I'd like to see this connected up to a PC somehow and used to play SteamVR games. You can attach a vive tracker to the headset and with a simple config file change in steamvr.vrsettings make it work as the headset tracking and get full 6DOF tracking compatible with base stations. The other issue is getting SteamVR to detect the headset and actually output an image to it. I guess you'd probably have to write your own driver for SteamVR, but I suspect there is already an open source driver somewhere you could use as a base.

[@eatbsreal]

I'm currently building a CRT viewfinder-based headset using Relativity VR, which by using an Arduino and some open source firmware it will enable it to be fully supported by SteamVR as a display out, as it just uses extended monitors for video out, and I'm also using HDMI to Composite converters. If I ever get any of it working I'll see if I can upload a video but it will be a lot more amateur than what was made for this video.

[@DanielKorgel]

Great project, the headset looks very 'sword of damocles' like, which I hoped you'd do. Awesome!

[@shaneneyome]

Next add six dof tracking using the ir cameras from wiimotes and ir LEDs mounted to the headset.

[@MatthewHolevinski]

totally made me think of johnny lee's channel

[@PeachIceCreamy]

Just slowly start turning it into a sort of Rube Goldberg machine lol

[@shaneneyome]

@@PeachIceCreamy ha

[@DBZHGWgamer]

@@PeachIceCreamy Nothing like a Rube Goldberg machine. A Rube Goldberg machine attempts to complete a very simple task in a very complex way. This is attempting to complete a very complex task in an equally complex way.

[@jhonviel7381]

@@PeachIceCreamy haha yeah you stupid!

[@plapbandit]

Add a hip mounted battery bank for wireless capability

[@MatthewHolevinski]

Then start screening for the new movie "The Wizard 2"

[@lewismassie]

Every time I look at the price tag of VR headset all I can think is "That's just motion tracking and software. I could make that" and then I never do. Glad someone did

[@Skarredghost]

It's a super-crazy experiment! I love it

[@Bowa10000]

If you use Electron you could remove a bunch of overhead and a few of those programs and still have the window cover both eyes without the tabs. Also now I want to build one.

[@kennylex]

I think the future of VR will go back to rays in some ways, with two pen sized devices at each side if the head that shoot beams onto a fasette prism that reflect the image onto a screen that is focusing most of the light back towards the eye, in that way the headset will be well balanced if you then go back to the 90th with a belt clip that hold batteries and tech not needed in the headset.

[@jampakdd]

This is cool as hell! I'd actually love to see this kind of Side projection in more mainstream designs.

[@jumoogde]

he always makes the best projects!

[@malcolmvanorder5453]

Considering the low resolution of the composite signal, it would probably help with frame rates to lower the hdmi resolution and not render unneeded pixels.

[@RND_ADV_X]

This seems like it would be a great prop for an alternate history film. Some Terry Gilliam style cyberpunk dystopian nightmare. And that's not really an insult. I'm baffled that you knew how to wire an HDMI to an old CRT, and then programmed it to work as a VR! Awesome :)

[@stapuft]

Oh wow i am super impressed, that is really cool! Keep up the great work!

[@stevy2]

The Pi 4 actually has composite video through the 3.5mm audio jack. The adapter wasn't necessary, although you lose audio output entirely.

[@andywest5773]

Yes, but I don't think you could get stereoscopic 3D without halving either the resolution or the frame rate. I used both HDMI outputs in this project.

[@SMGJohn]

A 720p CRT VR headset with 100Hz must be a dream come true and in colour, there would be no motion blur whatsoever, its really sad that they no longer make CRT except for medical equipment and turbo high end TV studios.

[@sunzithekupa6858]

dude i haven't watched these guys in year good shit 👌👌

[@ObiTrev]

Small world! I've been making the exact same thing for the past couple of years with a pair of crt viewfinders and a raspi-3. However, I'm working on a composite video splitter like the ones used on old VHS 3D movie systems.

[@viniciusnoyoutube]

Wow, so much knowledge in one project. Great job.

[@fringedwig4670]

i respect anyone who uses that keyboard

[@MWMTex]

What would have been nice was a list of all the parts used, your cost of the parts and wiring diagrams etc.

[@saucetelevision7915]

That was honestly really cool and impressive!

[@LegendBegins]

This is the kind of hackjob I absolutely love. Great video!

[@Chriva]

This guy is mad and I love it! :D

[@AndroidFerret]

Absolutely amazing... Really that blew my mind.... So it could have been possible to build a vr headset like this 10 years ago?

[@RealCadde]

And in the future, a VR headset will be a fully self contained unit to where you can walk around a football field without any wires attached and no need for wireless communications. You will be wearing everything from the processing power to batteries and headset as well as tracking components and they will be very slim fitting and super durable so you can actually roll around on the ground without damaging anything. The next step after that will be The Matrix of course.

[@RockstheSquirrelMobian]

As long as it does not contain batteries from Samsung. Burst into flames on head and acid spills.

[@cyrfung]

It's so cool. Like something from Back to the Future.

[@UNSCPILOT]

Or Bladerunner, kinda cyberpunk-ish

[@RhizometricReality]

I'd love to see the return of small crt vr

[@RetroPlus]

I like the idea of modern technology with cathode ray tubes revisited. This should be a real thing

[@Lumibear.]

Amazing! I have wondered if they’d work better for vr... *(edit)* CRTs I mean, just for the look of it, as they slightly ‘merge’ the pixels so you shouldn’t get so much awareness of the dot matrix, and they produce their own light so blacks should appear pretty solid. The weight’s a problem though, huh? And I imagine you were aware of the outer border?

[@cesteres]

Those old cam viewfinders usually have pronounced screen door.

[@Lumibear.]

cesteres I used to use them back in the day (big heavy camcorders that took full sized vhs cassettes) and I just can’t recall now tbh. I do remember being more aware of the pixels when they switched to lcd but that may have been cuz in the early days they were really low res panels.

[@JohnSmith-sk7cg]

CRTs don't have dot matrix. It's a single beam that changes intensity as it drags across a layer of phosphor.

[@Lumibear.]

John Smith “A CRT monitor contains millions of tiny red, green, and blue phosphor dots that glow when struck by an electron beam that travels across the screen to create a visible image.” So a bit of both, they’re sort of staggered together in tricolour batches, on a standard colour CRT. But if my ancient old Vectrex console is anything to go by, I think that uses a vector display fired up in a standard B&W CRT and there don’t seem to be any individual pixels or dots at all on that, just pure smooth phosphor light wherever the beam hits, so I think you’re right about that type having no dot matrix at all.

[@JohnSmith-sk7cg]

@@Lumibear. Color is usually done with a mask rather than individual phosphor dots. But yes, that does not exist on a black and white television. It's a uniform phosphor coating with no masking element.

[@PineappleFox]

This was cool to watch!

[@BeFs]

This was an awesome project! Inspiring!

[@wingdingdmetrius8025]

I can't believe you guys! so wild and cool. I was reading about using camcorder CRTs and immediately thought about using two of them for a stereoscopic image viewer... and here you guys are making a damn vr headset! and the vid is from a month ago.. great minds think alike friends ;-) 2020 gonna rock

[@grizeldiSLO]

Next step: write an OpenVR driver for it so it can be used with most SteamVR applications. You could also strap a Vive puck on top of it to get full 6dof tracking.

[@devicemodder]

to correct the image, we'll rotate one of our virtual cameras 180 degrees... or just flip the polarity of the vertical deflection coil...

[@stapuft]

Oh man, i did something similar using old camcorder viewfinder screens for eyepieces, and those "one time use" "disposable" digital cameras, and soem IR LED's to make a set of night vision goggles. With a variable pot to dim rhe displays. And some sugru to hold it all together to a dollar store set of "safety goggles" it actually held to my head rather well even though it was kinda heavy. My advice, use betrer goggles to makenit more comfortable and or mount it to a hat (or even a mask!) to keep the weight off your face.

[@TommyHelgevold]

The sad part about this is, if you had shown a video like this, lets say 6 years ago - you'd be working with VR as a full time developer by now. Technically, we could have made this back in the late 80s, but technology was insanely expensive, and most of us just kids without deep pockets. But yeah, thanks for the video, it's fun to revive old thoughts an memories, and see someone actually did it - even today!

[@myztklk3v]

"tweak the code" *comments out the return* im not even a programmer but that made me laugh.

[@murderdoggg]

It looks super cool as well

[@yarden-zamir]

Why not connect it to a desktop computer instead of a pie? You can then take advantage of the "refresh rate" of the crt as well as the resolution benefits, you can also use dp instead of hdmi

[@phillipdevereaux9626]

I think that it will take quite some time for displays to catch up with the black levels and response time of CRT at a reasonable price range. Too bad this isn't more practical. I bet CRT VR would look great pushed to its extremes.

[@BlameItOnGreg]

Now make a rotating camera rig with cameras that have analog output, and feed those signals straight to the CRTs and you’d have analog stereoscopic telepresence!

[@kquote03]

3 things I would have never thought to combine in my life

[@bitwize]

How's the latency? IME the HDMI-composite transition introduces quite a few frames of lag, up to 1/10 s or so.

[@thoughtsofapeer]

Best looking VR headset I've seen to date :D

[@AmeshaSpentaArmaiti]

I kind of want to see this turned into a scouter that display people's power levels with 80s-style sci-fi GUIs.

[@kenball1980]

Cool concept! Be ready for Oculus to show up at your doorstep.

[@grummus]

you know, the Raspberry pi 4 has composite out if you use a TRRS to composite cable in the audio jack

[@paulpjr3224]

Marty - "You mean to tell me that you built a VR headset to play VR with a Pi 4 and camcorder CRTs? Wow that's heavy."

[@AmaroqStarwind]

To make the software faster and more efficient (because for VR, faster is better), you should switch from Python/JavaScript/in-browser to compiled ASM.

[@Panyc333]

CRT framerates seem perfect for VR. I think you are on to something.

[@nexxusty]

Framerates? Lol.

[@Panyc333]

nexxusty sorry. Refresh rates.

[@chibibobo]

Great project, and well shot too!

[@RobotsEverywhereVideos]

this guy won cyberpunk before the game even came out. respect

[@XZenon]

This is so hacky, I love it! But you should really look into using the pins on the Raspberry Pi to output the composite signal directly instead of using the HDMI converters. Composite isn't that hard hard to utilize, the load on the Pi will be smaller and the image should be much clearer!