Stereo Microscope HUD dispay - is it possible?

[dicky96]

Hi guys
This post follows on from a discussion I am having with several members on badcaps forum.   So apologies to anyone who also follows that forum.  In the end we thought the folks here may have a better idea if our idea is do-able.

We were discussing the practicality and desirability of having a HUD type display built into a binocular or trinocular microscope so that it would be possible to view meter readings and possibly oscilloscope wave forms while diagnosing faults on DUT such as laptop & desktop motherboards or mobile devices, without having to move your eyes from your carefully placed test probes. 

We discussed several ideas from wearing smart glasses or some other sort of HUD when using the microscope, to having an OLED or other display integrated into the microscope or a modified eyepiece, or having a scanning laser or other device clipped on the microscope to project a small image directly onto the DUT itself (given that PCBs are relatively flat and reasonably reflective)

We briefly chatted about using blue tooth to get the data from a compatible multimeter onto the microscope display.

That's about as far as we got with it.  But we are thinking you eevbloggers could get further 

So the questions are...

Is it a desirable/workable feature?
Is it feasible to do this, as an 'affordable plug in add-on' or upgrade to an existing stereo microscope such as the common Amscope and similar models that are all over aliexpress?
Has it already been done?
How would it best be implemented?
Is this a good kickstarter type project for someone?


Cheers
Rich

[KaneTW]

Transparent fluorescent coating that you excite with a UV laser + UV filter?

[Dannyx]

Hi everyone. One of the guys over at Badcaps involved in this discussion is me, so I'm following along here

[KaneTW]

https://www.lumineq.com/applications/optics

Could also project a LCD display on a reserved segment of the optics.

[Dannyx]

The biggest hurdle I see is where and how you'd install the display in the microscope as an add-on without damaging the scope. The trinocular port seems to make the most sense, except it would have to work in reverse. I'm no optics expert so I don't know what's going on in there exactly :|

[KaneTW]

Just make it an alternate eye piece.

[Dannyx]

Just saw the insides on one of these microscopes shown here *struggling to work out how to insert links*....is this right ?

[dicky96]

https://www.lumineq.com/applications/optics

That sort of thing looks like it would work but I'll bet it is also expensive

[Dannyx]

Yes, that looks like the most "professional" and viable option, but the most expensive too, no doubt...

[ebclr]

Nikon D200 has something on this concept

https://www.imaging-resource.com/PRODS/D200/D200VIEWFINDER.HTM

[dicky96]

The D200 thingy says it is not really usable as a viewfinder so I wouldn't think it would be usable in place of a stereo microscope

To be honest we were hoping for some sort of home brew solution that could be implemented at a low cost so users of these sort of microscopes could add it for like 50-100 euros or something like that

[ebclr]

A microscope that comes with this feature for sure will be a good seller,  something like D200 solution but already on the microscope. I guess  Dlp's will be involved in the solution


http://www.ti.com/dlp-chip/automotive/overview.html

[Dannyx]

Oh yeah, that's right: the viewfinder on SLRs is another good way of describing this. I forgot I had one at my old shop which had this in its viewfinder. It could work since you'd only need to display only a few characters at a time, provided you found a way to make it into an add-on as previously discussed, either inside the body somehow so it shows up in both eyepieces or inside the eyepiece itself.

[dicky96]

If you look at the way the binocular microscope is built, it has two completely separate optical paths, one for each eye.  The only time both go through a single lens is where the objective lens is fitted at the bottom (Barlow Lens)

However if the HUD was only present in one eye, wouldn't your brain just compensate for that and you would see it normally anyway?  It's not like you depth of vision for the readout itself.

I am also convinced such a device (a microscope that had this feature, or even better an add-on to existing microscopes) would be a very good seller as I doubt it is very expensive to do it.  I wish i had the skills, knowledge and time myself. Surely someone would like to take this project on?

Rich

[tv84]

My 50 cents:

I don't think it's an easy issue. The D200 viewfinder example is a perfectly controlled implementation and, in optical terms, very different than looking at a bi-trinocular microscope.

It would be very difficult to make something DIY that could be adapted to several equipments...

What about smartglasses/optical head-mounted display?

https://en.wikipedia.org/wiki/Optical_head-mounted_display

[Dannyx]

Yes, I agree it may not be easy overall. I was thinking an OLED display and somehow "projecting" it into the optical path. I think the only way to achieve this is with a prism (or a semi-reflective piece of glass like a teleprompter), since you HAVE to combine both the image from the display and the one which normally comes through the microscope, so you'd have to "insert" it somewhere, that's why I imagine the third port as a good place to start experimenting before taking stuff apart....just an idea. If I had a microscope myself, I would have definitely looked into it more...

[jfiresto]

I suppose you could put a bright, order 10mm diameter display at the intermediate image plane of the photo port: to project a focused image on to a flat specimen. That way, dust and such on the display would not noticeably degrade the specimen image.

If the specimen isn't flat, you likely want to project the image the other way, to the eyepiece instead of the specimen, so that you are essentially viewing two superimposed specimens. Unfortunately, most microscope systems assume just a single specimen with possibly two or more viewers. I wonder if you could find some sort of optical comparator.

[TERRA Operative]

I imagine an oled or LCD at right angles to the optic path with an angled piece of flat glass to reflect the displayed image into the eyepiece, kind of like a teleprompter or a Peppers Ghost type effect.

Oled would work well for this as the black is truely black so it won't wash out the image of the PCB, although a neutral density filter would probably help when using an LCD anyway.

The trick will be getting the optics right so both the image from the display and the thing you are looking at are both in focus at the same time.
I suppose it would be easiest to keep both focus mechanisms seperate as the display will never need to be refocussed once it is set. It will then always remain in focus while the thing you are looking at can be brought into and out of focus in the mormal way.
With the correct lenses, you can use a larger (hence cheaper) display, maybe a high DPI iphone display on a breakout board, maybe HDMI or similar to a Raspi or PC running some software to mirror the scope/Test equipment display.

Stick the display in a lightproof enclosure with the correct lenses then attach it to the microscope with that bit of angled glass in the right spot in the original optical path.

I have absolutely no idea about figuring out optics though..... good luck!

[dicky96]

What about my idea of using a low powered laser and voice coil operated mirrors to produce a scan or raster (like the animation lasers I used when I was using when running mobile discos - some of those you could type something on a keyboard project it onto a wall or even the dancefloor).

The laser and mirror assembly could be clipped to the microscope casing similar to how the LED ring light fits (hey, it could even be incorporated into an LED ring light!), and project a small image onto the PCB under test.  You could manually swivel the laser assembly to move the image wherever you want in the field of view.  It wouldn't matter if it was projecting from an angle and causing some key-stoning of the image.  You would still be able to read it.  A graticule and oscilloscope wave form should be easy to project as well as a meter reading.

The PCB under test should be flat and reflective enough to make the displayed image clear enough to read.  You could use a diffuser on the laser which would actually make the laser image easier to read and keep it safe to the eye if it was reflecting up the microscope at any time

As it is a laser it does not require focusing.

That sort of addon would potentially fit to any microscope and require no modification of the optics.

[jfiresto]

Just saw the insides on one of these microscopes shown here *struggling to work out how to insert links*....is this right....

The link looks good to me, but you probably do not want that fellow cleaning your microscope. You can actually hear him scrubbing glass.

[joeqsmith]

If you don't mind looking at an LCD monitor, you could feed everything you want on a PC and display it easy enough.   Maybe some better probe and board holders would help.   

[rt]

Some googling later .....

It looks like various groups have tried this before:

Novel Microscope-Integrated Stereoscopic Heads-up Display for Intrasurgical OCT in Ophthalmic Surgery
https://iovs.arvojournals.org/article.aspx?articleid=2333389



They insert a beamsplitter for each eyepath before the collimated beams get to the eyepiece optics and add a lensed image from an OLED display.


Or you could add an external single beamsplitter/45degree glass reflector to an OLED/etc at the same working distance from the objective lens as the PCB/DUT.
e.g.





rt

[dicky96]

Or you could add an external single beamsplitter/45degree glass reflector to an OLED/etc at the same working distance from the objective lens as the PCB/DUT.
e.g.





rt

Nice idea.  That looks like it could become something workable.......

[Marco]

It's a shame there is no open source solution for autostereoscopic eye tracked 3d displays. It's too boutique for any proprietary solution to ever be affordable , but hardware wise it's all cheap and COTS.

[tv84]

Nice idea.  That looks like it could become something workable.......

Yes, nice idea. BUT, the (hands/tools) working space becomes a big problem.