Mµ Thermal Imager - real or fake?

[mikeselectricstuff]

Fluke have a new product out, the VT-04 not-quite-a-thermal-camera:

http://www.farnell.com/datasheets/1751644.pdf

"Four times sharper" than the VT-02, apparently, though still no actual resolution figures quoted.

I read somewhere that these use a mechanical scanner + thermopile sensor - not sure if it's a single sensor or something like the Melexis chip

[CanadianAvenger]

Hahaha, now they're telling people where to go to get a cheap thermal camera

Hello All,

Things are coming along well. The iOS app is nearly complete. Just a few more tweaks to the the image processing and to saving the video. We're working on getting rid of some shakiness and making the auto-scaling of the IR gradients as good as can be. I'm looking forward to the completion of porting the app over to the other operating systems.

Some news from the IR industry this week. FLIR has released a new line of cameras. http://www.flir.com/thermography/americas/us/view/?id=61194

They seem like solid products, and their low end model with a resolution about a quarter of ours is retailing for under $1000.

We're happy that we'll be able to beat that price by more than half, with a camera with much higher resolution, video and still recording, greater storage capabilities (dependent upon your smartphone or tablet), and WiFi.  We also think our form factor allows easier use than the pistol grip.

But we're very happy to see the continuing drop in cost of so many IR products which are now being targeted at the mass market.

We're excited to be getting so close to launching our camera and enabling even more people to utilize thermography.

Cheers!

-MuOptics

[EEVblog]

Hahaha, now they're telling people where to go to get a cheap thermal camera

And STILL no actual thermal image after at least 9 months of R&D (they claimed several months before the campaign, and it's been 6 months after now).
Wow.
The backers have pitch forks at the ready and these guys don't address any of their concerns. Wow.
They have balls, I'll give them that. And that's likely all they have, plus the money, unless they have spent it all.

[mikeselectricstuff]

I am interested to see FLIR's take on visual and Thermal image merging. There is normally an image registration error but FLIR appear to have sorted that issue.

I suspect its only solved over certain distance ranges.

The down side of the stated new E series camera is the low resolution of the base unit. I surmise that the images in the brochures are from the higher resolution models and not the base unit.

Would be very interesting if all the E series used the same sensor, like the I series apparently did. 
Also may be some scope for tweaking lens distance for close-up  use.

Curiosity has got the better of me - Flir M4 ordered 

[EEVblog]

Curiosity has got the better of me - Flir M4 ordered 

I presume you aren't going to do a destructive teardown...
Flir have mentioned something on twitter about contacting me to get me one.

[mikeselectricstuff]

Curiosity has got the better of me - Flir M4 ordered 

I presume you aren't going to do a destructive teardown...
Flir have mentioned something on twitter about contacting me to get me one.

Not destructive (hopefully!) but will definitely be investigating mods for close-up work and investigating potential for resolution & framerate tweaks.
Might be good if you can get one of the higher-up models to compare - I suspect the higher res ones may have a different lens, even if the other hardware is the same
 

[EEVblog]

Not destructive (hopefully!) but will definitely be investigating mods for close-up work and investigating potential for resolution & framerate tweaks.
Might be good if you can get one of the higher-up models to compare - I suspect the higher res ones may have a different lens, even if the other hardware is the same

A close-up lens would be essential for PCB work I suspect.
Yes, most likely the same sensor in all the range.

[mikeselectricstuff]

A close-up lens would be essential for PCB work I suspect.

Most camera lenses can be made to work close up by moving them further from the sensor, so that's probably the first thing to investigate. Obviously the visble/thermal combining stuff won't work.

[Fraser]

As Mike states, if a lens can be distanced from the sensor, close-up focus is achievable BUT many low end thermal cameras use either fixed focus assemblies or a variable focus mechanism that does not offer easy modification for close-up work.

I approached this problem from the same angle as scientific thermal imaging and microscopy. It is common to fit an auxiliary lens to a standard thermal camera in order to provide a close-up focus capability. FLIR offer such lenses as optional items but they cost a small fortune. For my 570 or 695 models they would cost more than a new FLIR E4

The challenges are in selecting a suitable lens material, the focus distance and the diameter of the lens. A Germanium Bi-convex lens with a 6" focus distance works very well, but there are few such lenses available at reasonable cost. I did find some very reasonably priced Bi-convex ZnSe lenses of 20mm diameter and 4" focus distance. This lens costs only $30 from China and works very well, if a little small in diameter. ZnSe is an excellent lens material at thermal image wavelengths. The alternative material for a similar cost is GaAs, but this has a higher transmission loss and narrower band-pass characteristic. Just search e*ay for ZnSe or GaAs lens and you will find many CO2 laser lenses to choose from. I also purchased some suitable 20mm camera lens holders so that the lenses could be mounted on the camera more easily. Remember, if you modify your camera, you lose your warranty and make normal use of the camera difficult at longer distances. An auxiliary lens avoids both issues.

I was fortunate enough to find a new Inframetics Germanium 58mm diameter Meniscus close-up lens with a 6" focus distance designed for the purpose. The original cost was $6800  Its a scientific lens and rare as hens teeth. I  bought it for $150 and it works superbly on my FLIR 695 

I will attach some pictures of another (faulty) TIC's video processing SRAM at the PM695's normal 0.5m minimum focus range and at approx 6" (the last 2 pictures) using the Inframetrics lens. The far left SRAM chip is faulty ! Thermal images of PCBs can be both enlightening and helpful in repair operations.

Except in very high end TIC's, be careful with digital zoom. Just like a normal digital camera, you just get lower resolution and awful pixilation, especially when you are starting with only 320x240 pixels. My 695 can digital Zoom up to X4. X2 would be 160x120 pixels and x4 would be lowly 80x60 pixels.  It would be a bit of a joke to offer a digital zoom on a 80x60 pixel start point.

[Fraser]

For anyone interested, I will show the auxiliary lenses that I use with both my Ex Fire service cameras and the FLIR PM series.

The lenses are as follows:

1. Inframetrics single element Germanium Meniscus 6" Close-up lens 58mm.
2. Chinese GaAs CO2 Laser Bi-Convex 4" focus point lens 19mm in lens holder.
3. Chinese ZnSe CO2 Laser Bi-Convex 4" focus point lens 19mm in lens holder.
4. Commercial Germanium Lens protector, high transmittance coated 35mm.

The Inframetrics lens is interesting in that the concave side faces the target and the convex side faces the TIC primary lens. This lens offers excellent transmittance, anti-reflective coating and good depth of field. If you see one cheap, buy it !

This isn't a cheap one .......

http://www.ebay.com/itm/FLIR-Systems-100-m-Close-Up-Lens-LW-34-80-/121185050471?pt=LH_DefaultDomain_0&hash=item1c37311f67

Neither is this........

http://www.ebay.com/itm/FLIR-Systems-MACRO-LENS-50-MICRON-P-N-1700-500-/300951292680?pt=Camera_Lenses&hash=item4612184b08

The two Chinese Bi-Convex lenses are 19mm diameter and are symetrical. They fit perfectly into the 19mm filter/lens holders that were used on older compact cameras of the 1970's. Good Camera shops still have some old stock of these types of holders. The price of the holders is around $5 each.

The weird 'lens' with the plastic shell and red 'hood' is in fact a lens protector made from a very thin piece of Germanium for low through loss. The red fitment is used only to insert the protector into the lens aperture of the TIC for which it was designed. These lens protectors are expensive (approx. $250) but protect the even more valuable primary lens in the TIC. I will be mounting the protector on a filter step down ring for mounting on the TIC's.

A very cheap alternative to the expensive Germanium lens protector may be constructed using a filter holder and a sheet of 25 micron Polyolefin Shrink Wrap plastic. Its not perfect but is effectively transparent at thermal wavelengths. FLIR offer such cheap protectors as disposable alternatives to the more expensive options. I bought a 20m x 45cm roll of the Polyolefin Shrink Wrap for $7.50 

http://www.ebay.co.uk/itm/350800488552?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

That should last a few years. You can also make temporary external weather proof housings using the shrink wrap as the face plate. Great for wildlife observation which is what I intend to do with my cameras.

For anyone wondering why Germanium lenses are so expensive, they have to be grown as a single crystal of Germanium. The crystal is then cut and ground to the same optical standards as instrument grade vision wavelength lenses. The lens is then coated with a special anti-reflective coating (at thermal wavelengths) to improve its performance. Think carefully before buying a Germanium lens with damage or coating loss. This will degrade performance seriously. Sharp impact can cause a Germanium lens to suffer micro fractures within its single crystal structure....very bad news !  In summary, thermal camera lenses are a very specialist product that is made to very exacting standards. The price increases exponentially with diameter which is why the cheaper cameras have small lenses and so are less sensitive. \take a look at my PM695 primary lens ....its almost 60mm in diameter and the internal focussing lens is 50mm diameter  = Very expensive

[Fraser]

An impressive thermal camera picture taken during this weekends Korean Grand Prix.

The car caught fire 

I hadn't realised F1 had live TICs on the cars these days. Excellent application of the technology  I presume they are normally looking at the tyre surface temperature.

[firewalker]

[firewalker]

[bookaboo]

Interesting info all round.

I'm thinking about getting myself a Flir I3 to help with fault finding work. Would it be high enough resolution to help with PCB work?
What I'm thinking of is that it could help find which components are shorting or which areas of a board are "dead" i.e. no current flowing.

Has anyone used Flirs for this and if so what's the lowest model you would recommend?

[mikeselectricstuff]

Interesting info all round.

I'm thinking about getting myself a Flir I3 to help with fault finding work. Would it be high enough resolution to help with PCB work?
What I'm thinking of is that it could help find which components are shorting or which areas of a board are "dead" i.e. no current flowing.

Has anyone used Flirs for this and if so what's the lowest model you would recommend?

The problem is not resoution but close-up focus. Stay tuned on this...
I think the  E4 is better than the i3 at similar price -  may be some cheap i3's around though- not clear if the E4 is actually shipping yet - it's not in RS/Farnell etc.
I couldn't find a place that showed stock levels - I ordered on Fri PM so have only had an auto acknowledge email so far.

[Fraser]

I will take an 80x60 resolution image of the same chips that appeared in my earlier post. You can then see what sort of image the i3 may produce. As Mike says, the E4 is a different creature as it uses a visible image overlay to provide edge detail that low resolution thermal cameras cannot produce. Very clever. As you will have seen, clos-up focus is achievable for $30 so no biggie there.

Watch this space.

Fraser

[mikeselectricstuff]

I will take an 60x80 resolution image of the same chips that appeared in my earlier post. You can then see what sort of image the i3 may produce. As Mike says, the E4 is a different creature as it uses a visible image overlay to provide edge detail that low resolution thermal cameras cannot produce. Very clever. As you will have seen, clos-up focus is achievable for $30 so no biggie there.

Watch this space.

Fraser

I think the question is how well 80x60 will work without the overlay. For close-up work, the issue of figuring out what you're looking at may be less as you can wave things around close to the subject to find where you are. 

[Fraser]

Well that was an interesting little test. FLIR may have outwitted me here.

I set up my PM695 to view the SRAM and another chip on my PCB.

The camera was set to normal 320x240 (x1 electronic zoom) with the close-up lens, the picture framed and recorded. I then set the camera to 80x60 (x4 electronic zoom), reframed the shot  without the close-up lens and recorded the picture.

To explain why I did this... the minimum focus distance of the camera is 0.5m. At this distance, using the x4 zoom you can get a close-up of the chips. When in X1 zoom I have to move closer to the chips to get the same frame contents. As stated 0.5m is the closest I could go without a close-up lens, hence why I had to use it here.

I was surprised at the recorded results. It appears that the PM695 uses image enhancement technology to improve the lower resolution image created when using the electronic zoom. For this reason my pictures may not give you a true impression of what an 80x60 camera will produce. But FLIR may include the image enhancement technology in the consumer cameras as well  ? I note that the PM695 produces a 320x240 image file no matter what zoom is used when framing the image. I suspect intelligent interpolation is at work here. IriSys do the same with their 16x16 pixel chips to produce a 48x48 pixel image.

I knew the PM695 was a clever bit of kit but I had not expected this 

Note that the PM695 produces proprietary high quality image files or lesser quality BMP files. I used Irfanview to quickly convert the BMP's to JPG so some image quality may have been lost.

Fraser

[EEVblog]

I'm thinking about getting myself a Flir I3 to help with fault finding work. Would it be high enough resolution to help with PCB work?
What I'm thinking of is that it could help find which components are shorting or which areas of a board are "dead" i.e. no current flowing.
Has anyone used Flirs for this and if so what's the lowest model you would recommend?

The FLIR's are not suitable for PCB inspection (at least the cheap ones without lens attachments), you can't focus close enough, they are designed for distance work.
Here is some thermal images from a ULIR brand TI160 TIC with suitable close up lens, provided by Charles at Trio Test
You won't get a that sort of close up PCB work without a suitably designed closeup lens.

[Fraser]

To assist those who are wondering what can be done with a $30 ZnSe close-up lens, here are some really rough pictures. The lens is normally used on my Fire Fighters cameras that have a 20mm lens. My FLIR has a huge lens so some awful bodgery was needed, involving an aluminium lens flange, some cardboard and masking tape. I didn't expect much as the 20mm ZnSe lens is way too small for the PM695 lens aperture. The comsumer grade FLIR's like the i3 use a much smaller lens so no such issue would exist.

My PM694 was effectively looking thorough a 'keyhole' but it did work.

You will see that I have been able to get up close (4") to the SRAM and GAL chips. There are lots of inefficiencies, lens misalignment etc, so more noise is present but that does not occur on my Argus Fire cameras.

The greatest challenge will be to buy a TIC at a decent price. You can then add one of these simple auxiliary lenses and start looking at PCB's. There will be temperature measurement inaccuracy caused by losses in the ZnSe lens but I would expect them to be minor for hobbyist use.

[Fraser]

For anyone wondering where to buy a suitable ZnSe lens, I bought mine here:

http://www.ebay.com/itm/ZnSe-GaAs-Focal-Lens-for-10-6um-Co2-Laser-Engraver-Cutting-Machine-12-25mm-1-4-/321078811086?pt=LH_DefaultDomain_0&var=510102779696&hash=item4ac1c9d9ce

You are looking for a ZnSe lens with a decent focus point in front of the lens. The best I could find in these cheap CO2 laser lenses was 100mm (4"). Pick the diameter that best suits your cameras lens aperture or whatever mount you are going to use. I leave the mechanics of mounting the lens to you but it should be treated with care as it is a soft material and easily scratched. I use proper lens holders and adapt them to the camera.

[EEVblog]

The greatest challenge will be to buy a TIC at a decent price. You can then add one of these simple auxiliary lenses and start looking at PCB's.

That's the trick. As Mike said, the affordable low res FLIR ones really need that optical camera part to give you a good visual outline of what you are looking at, and that will almost certainly be completely screwed with an external lens.

[Sparkey_500]

I've been following this topic for awhile and I finally decided to make an account to add my 2 cents to the discussion. What about using IR Transmittable Ink coated on a standard lens?

http://www.teikokuink.com/en/product/techreport/146_tech.html

[bronzies]

I've looked at some fluke thermal imagers, they are so expensive. This one probably will be too looks like.

[CanadianAvenger]

I've been following this topic for awhile and I finally decided to make an account to add my 2 cents to the discussion. What about using IR Transmittable Ink coated on a standard lens?

http://www.teikokuink.com/en/product/techreport/146_tech.html

That's for Near IR, thermal cameras work in the Far IR range. A standard Camera sensor is not capable of receiving Far IR wavelengths.