Does scopes have "Z" axis ?

[CatalinaWOW]

There were many clever and useful applications for the "z-axis" on oscilloscopes.  If you can bend your mind to ignore the association of z with the third axis in a Cartesian coordinate system you can probably figure many of them out, and perhaps invent something new.  It is another way of presenting information.

An example that might trigger more interest in today's generation:  Use one of the interrupts in your system (latched and cleared with the interrupt clear or return as appropriate in the system you are using) to drive the z axis.  Then the display will only show during that interrupt and you can see the signals bouncing uncorrupted by whatever they are doing in other interrupts or in the main/background routine of the system.  As long as the interrupts occur repeatedly at intervals shorter than the phosphor decay time (usually a few milliseconds) you will get a nice view of what is going on.

[MLXXXp]

The best use I found for the Z-intensity input of a scope was to play Spacewar!

As described in the "Ports to other systems" section of  this article: https://en.wikipedia.org/wiki/Spacewar_%28video_game%29#Ports_to_other_systems, I used two 8 bit DACs connected to my 8080 system, feeding the scope in X-Y mode, plus another output bit connected to the Z axis to turn the beam on and off.

In my high school electronics lab there was a teaching scope with a big TV CRT for the screen. I was really nice to use that to play it on.
This was back in the late 1970's.

[w2aew]

Fun Fact: the fact that analog scopes have an X, Y and Z (intensity) inputs is why the iconic Tektronix application note "XYZs of Using an Oscilloscope" is named that way.

Here are two videos I did that utilized the Z input:

[GK]

3D displays on an analogue X-Y scope:

http://www.glensstuff.com/3dpu/3dpu.htm

[tggzzz]

3D displays on an analogue X-Y scope:

http://www.glensstuff.com/3dpu/3dpu.htm

2D display of a (nominally) 3D object.

[GK]

3D displays on an analogue X-Y scope:

http://www.glensstuff.com/3dpu/3dpu.htm

2D display of a (nominally) 3D object.

Is this kind of pedantry supposed to make you look smart? Read the introductory paragraph.

[fcb]

I loved the PM3394B - amazing scope. If you get chance the to get one GET IT.

I know exactly what you are saying.
Over the years I have bought every single one that had a good price and was in good condition.
Right now I probably have at least 10 of them.

The specialty was with "all options" and I was lucky enough to get 6 of them in a bundle from a
government sale in the US a few years ago.

These days, people have less and less appreciation of this amazing scope.
I usually use 6 of them at once on my high voltage bench.

Now I'm not an envious person - but today I'm making an exception!!!

I had one back in 1995 (bought new for £5500+VAT) - I miss that scope so much.

[vk6zgo]

There are two meanings of "3D". The real one that has been around for >150 years, and the computer weenie one which is really 2D or, to stretch a point, 2.5D.

Perhaps this might be of your interest https://www.oculus.com/en-us/ ? (Or any competitor in field of head mounted displays, there are plenty and consumer versions are just behind the horizon.)

In early 2013 I tried an early Oculus when they kindly brought it to show my local HackSpace and University. I spent 5/10 minutes playing a VR video game. The resolution was low, but that's not a fundamental and I believe they have already improved it. I was interested in whether it might eventually work with the Condor gliding simulator, where you spend a lot time going in circles and/or spinning towards the ground e.g. real life

or simulation
http://www.condorsoaring.com/media/movies/Discus2%20spin%20cockpit.zip
. 

Nice gliding video,but they spoilt it with the dumb background music.
(I didn't look at the simulation-------sorry!)

Half of the experience of gliding is the near silence,with only the slight sound of air rushing over the aircraft.
In straight & level flight,there is very little sensation of forward motion.

[vk6zgo]

The simulation has captured the sound pretty well---not quite,but almost.
I needed to wind the volume right down,& as I said,it was close.

I joined a Gliding club back in the day,but it didn't fit well with shift work,& then,when I met my wife,that was goodbye to Gliding!

[tggzzz]

3D displays on an analogue X-Y scope:

http://www.glensstuff.com/3dpu/3dpu.htm

2D display of a (nominally) 3D object.

Is this kind of pedantry supposed to make you look smart? Read the introductory paragraph.

Clear and accurate, not smart. Read the thread drift.

[tggzzz]

Half of the experience of gliding is the near silence,with only the slight sound of air rushing over the aircraft.
In straight & level flight,there is very little sensation of forward motion.

Noise depends on how fast you are going; it is a good way of assessing large changes in airspeed without looking at the ASI. Too quiet => wake up fast!

What's straight and level flight? I'm always hunting for lift, chasing after buzzards, or just having exuberant fun. It is claimed that glider pilots that transition to powered flying have two problems: realising they can fly straight and level , and then managing to stay awake while doing do.

[tggzzz]

I joined a Gliding club back in the day,but it didn't fit well with shift work,& then,when I met my wife,that was goodbye to Gliding!

Maybe you'll reconsider when you have a child (wonderful for their self-confidence, maturity, CV, being with them for longer), or decide that a little absence from a wife can make the heart grow fonder Have fun, safely.

[GK]

3D displays on an analogue X-Y scope:

http://www.glensstuff.com/3dpu/3dpu.htm

2D display of a (nominally) 3D object.

Is this kind of pedantry supposed to make you look smart? Read the introductory paragraph.

Clear and accurate, not smart.

Correct on the last point.

Read the thread drift.

I did.

Note, I have been taking 3D photos for 30 years (with a 1940s vintage camera https://en.wikipedia.org/wiki/Stereo_Realist ), so I have some experience of the subject.

Surely you meant stereoscopic photographs.
 

[Warhawk]

I loved the PM3394B - amazing scope. If you get chance the to get one GET IT.

I know exactly what you are saying.
Over the years I have bought every single one that had a good price and was in good condition.
Right now I probably have at least 10 of them.

The specialty was with "all options" and I was lucky enough to get 6 of them in a bundle from a
government sale in the US a few years ago.

These days, people have less and less appreciation of this amazing scope.
I usually use 6 of them at once on my high voltage bench.

Nice collection, what is "that" special on these scopes ?

[tggzzz]

Surely you meant stereoscopic photographs.

Evenly divided. Some clubs are 3D, some stereoscopic, some stereo-3D. Here's a list of "3D clubs worldwide" http://www.stereoscopy.com/clubs/

3D photographs and projection systems have been around for >100 years. The only way of seeing 3D is to have two images, one for each eye.

[vk6zgo]

Half of the experience of gliding is the near silence,with only the slight sound of air rushing over the aircraft.
In straight & level flight,there is very little sensation of forward motion.

Noise depends on how fast you are going; it is a good way of assessing large changes in airspeed without looking at the ASI. Too quiet => wake up fast!

What's straight and level flight? I'm always hunting for lift, chasing after buzzards, or just having exuberant fun. It is claimed that glider pilots that transition to powered flying have two problems: realising they can fly straight and level , and then managing to stay awake while doing do.

The old Blanik I learnt in seemed quite capable of flying very slow & straight & level,& was very quiet.
I wasn't up to chasing buzzards,even if we had any around here.

I had one adventure  while learning,when the tow parted at 400ft(my fault).
The instructor got us down with a minimum of fuss,but those big jarrah trees at the end of the paddock were looking bigger all the time!

[tggzzz]

Half of the experience of gliding is the near silence,with only the slight sound of air rushing over the aircraft.
In straight & level flight,there is very little sensation of forward motion.

Noise depends on how fast you are going; it is a good way of assessing large changes in airspeed without looking at the ASI. Too quiet => wake up fast!

What's straight and level flight? I'm always hunting for lift, chasing after buzzards, or just having exuberant fun. It is claimed that glider pilots that transition to powered flying have two problems: realising they can fly straight and level , and then managing to stay awake while doing do.

The old Blanik I learnt in seemed quite capable of flying very slow & straight & level,& was very quiet.
I wasn't up to chasing buzzards,even if we had any around here.

I had one adventure  while learning,when the tow parted at 400ft(my fault).
The instructor got us down with a minimum of fuss,but those big jarrah trees at the end of the paddock were looking bigger all the time!

Modern gliders are much quieter - unsurprising since noise=drag. Even so, they are noticably noisier at 100kt - and probably much much noisier at 200kt ;}

Round here sometimes the buzzards come and join you in a thermal, which is a delightful complement to your flying skills.

I've done very few aerotows, but had many winch cable breaks - great fun, except for the walk back! And deliberately entering spins at ~1000ft is fun too.

[GK]

Surely you meant stereoscopic photographs.

Evenly divided. Some clubs are 3D, some stereoscopic, some stereo-3D. Here's a list of "3D clubs worldwide" http://www.stereoscopy.com/clubs/

3D photographs and projection systems have been around for >100 years. The only way of seeing 3D is to have two images, one for each eye.

LOL. The Stereo Realist camera took 2D stereoscopic photographs (which merely give a very limited illusion of depth when viewed with the correct apparatus) , not 3D photographs in the true sense of the term. In that regard "3D" is a misnomer and a pendant like you shouldn't be using it. Or perhaps you managed to modify your Stereo Realist for holography.

As for my use of the words "3D display" in reference to my linked-to electronics project, I was clearly using the term in the same context as the title of the reference text that I cite: http://www.glensstuff.com/3dpu/ref.jpg . I posted it because I figured that it was relevant to the OP's question about the possible utility of a Z-axis input for an oscilloscope display; not a response to any of your posts.
   

 

[tggzzz]

Surely you meant stereoscopic photographs.

Evenly divided. Some clubs are 3D, some stereoscopic, some stereo-3D. Here's a list of "3D clubs worldwide" http://www.stereoscopy.com/clubs/

3D photographs and projection systems have been around for >100 years. The only way of seeing 3D is to have two images, one for each eye.

LOL. The Stereo Realist camera took 2D stereoscopic photographs (which merely give a very limited illusion of depth when viewed with the correct apparatus) , not 3D photographs in the true sense of the term. In that regard "3D" is a misnomer and a pendant like you shouldn't be using it. Or perhaps you managed to modify your Stereo Realist for holography.

Everything is "limited" in some way or another, so that isn't a distinction that throws any light (ho ho) on the subject.

As you correctly imply, holography != stereoscopic/3D - but that rather invalidates your point. Yes, I realise that many people are now starting to grossly misuse the term "holographic" - but that's irrelevant to this discussion.

I'll take holography seriously when it can show me an image of a candle or a chandelier or the sunset.

[GK]

Everything is "limited" in some way or another, so that isn't a distinction that throws any light (ho ho) on the subject.

As you correctly imply, holography != stereoscopic/3D - but that rather invalidates your point. Yes, I realise that many people are now starting to grossly misuse the term "holographic" - but that's irrelevant to this discussion.

That doesn't make sense

I'll take holography seriously when it can show me an image of a candle or a chandelier or the sunset.

Then I'll take stereoscopy and any pretensions of 3-dimensionality seriously when additional information about the subject can be reliably attained simply by altering the viewing position.

[SL4P]

Oh well, while we're all talking 3D and  2.5D...

If you're rendering 3D on a 2D surface - eg screen or printer.
Once you've identified your viewport surface and vanishing point coordinates...

You can scale your depth information back toward that vanishing point, (or project it forward toward the viewer) by decreasing (or increasing) the XY offset from the imagined line drawn between the viewpoint and the vanishing point...

A scaling value of approximately 0.6 gives a focal length that is close to that of the human eye's perception of perspective.  Changing the value changes the 'focal length' of the 'image' presented to the viewer.

Have fun... this is the basic principle of 3D wire frames- and obviously with depth shading and light sources added you can do a lot more!

[Alexei.Polkhanov]

For a 2 input oscilloscope I would expect X-Y mode to be available, for 3 input - X-Y-Z with a 3D diagram shown and for 4 input scope it could be a 4D diagram with 4th dimension translated to colour etc. My assumptions based on the fact that graphs like these are available in any math package like MATLAB or Mathematica, R etc. For high speed oscilloscope it is probably too expensive to provide that kind of functionality and usefulness is limited. 3D is a default plot for Real Time Spectrum Analysers.

In my Agilent DSO even X-Y sucks comparable to Tecktronix for example - that blurry, pink graph that they generate - I hate it. So if I want something pretty I record the trace to and then import it in MATLAB/OCTAVE - that is what this guy have done in this video:

[kony]

I'll take holography seriously when it can show me an image of a candle or a chandelier or the sunset.

You won't see true holographic recording of something, that is lightsource by itself, noncoherent by its nature. (Holographic recording with single noncoherent lightsource is possible, but only in limited and well defined optical path (read: microscopes, etc.)).
But as I already mentioned, there is a way around this (good 'nuff for digital era):
http://www.bmva.org/bmvc/2014/files/paper040.pdf
http://home.otoy.com/otoy-demonstrates-first-ever-light-field-capture-for-vr/

You won't see lightfield videos for few years unfortunately, as it is obscenely data intensive - perhaps somebody comes with brand new compression method, as there is plenty of redudancy in image data.

[dom0]

That's not really how it works.

To map real 3D objects (like a 3D model) into a flat, perspective image (2D) projective geometry is used.
Specifically: you (almost always) use a euclidean 3D space embedded in a projective 4D space (w=1, these 4D vectors are normalized homogeneous coordinates now). Then you can easily calculate a transform (as a 4x4 matrix) to map vectors in said space to a 4D space, manipulating image plane, fov, ... and so on. In conjunction with a w=1 normalization (perspective divide) you'll get your 08/15 flat 3D space. This 3D space is usually a unit space (hardware clips everything outside (-1,-1,-1)-(1,1,1)).

As your vectors probably represent fragments since a few steps you would do a simple Z (depth) comparison to decide whether to update a pixel in the frame buffer with a new fragment or not.

That's the gist of it.

[SL4P]

That's not really how it works.

You're right of course...  I was trying to present a simple method for embedded bit-mapped solutions that presents the 'almost as good as' 3D visualisation, and specifically used in those days before we had powerful co-processors and GPUs.
Thanks for bringing that to the table!  Cheers.. (BTW the mention of clipping was important. thanks!)