EEVblog Electronics Community Forum
Products => Thermal Imaging => Topic started by: NiallxD on May 09, 2020, 05:32:13 pm
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Hello!
I've just finished up my Thermal Telescope prototype and thought I'd share it with you all. I'd welcome any feedback as this is the first optical device I've ever made.
Lenses used:
- 38mm dia Trumpf ZnSe lens (negative meniscus - 190.5mm FL)
- 20mm dia MCW ZnSe lens (plano-convex - 38,1mm FL)
Camera:
- Seek Compact Pro FF (iOS)
Extra Parts:
- Female to Male Lightning adapter
- Many 3D Printed parts. All bespoke.
Now, this is a prototype and I will be refining it some more, including redesigning the parts to improve the overall design. Was having a nightmare getting the images inline without been humongous so just attached for you to take a look at. Also, a small clip of a pigeon too https://youtu.be/TX-Pc-LAoUw
The magnification is approx 7.75x, which is great for what I want! Simple slide action can be used for focusing if needed.
Areas I'm aiming to improve:
- Image circle size. I'd like to maximise the image circle so that it covers the entire sensor. This could be a limitation to these lenses as their job is to focus the laser down to a small point minimising waste (hence the negative meniscus).
- Mount stability.
- Include amount for an iPhone 5s so I can mount the whole package together.
- Better fixing for the camera. Currently held in place with tape :-+
That's about it for now, hope you find this somewhat interesting! :-+ And a major thank you to @winternight95 for the lenses & @Fraser for the heads up!
Cheers
Niall
(https://i.imgur.com/vQuFjrR.jpg)
(https://i.imgur.com/GvveUEX.jpg)
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Which image can you get, if you place lens just in front of seek compact lens?! Can you see smd chip with 38mm dia Trumpf ZnSe lens?
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If you are asking what the close focus is like then pretty good. Though that lens is overkill, a 20mm works great and can focus down to about 25mm.
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Congrats Niall , great work, I will try to replicate it
looking for the parts do you know if it possible to use another diameter for this lens 38mm dia Trumpf ZnSe lens (negative meniscus - 190.5mm FL)
up to 20mm diameter are cheap but 38mm skyrocket
Thanks!
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Hey there,
It was a great project to work on! You can buy decent lenses here for a good price! The smaller lenses might not work as well, even at this size it’s not great!
If you want any STL’sn let me know.
https://www.ebay.co.uk/itm/254602422621 (https://www.ebay.co.uk/itm/254602422621)
Cheers!
Niall
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Thanks Niall,
have you thought of selling full telescopes yourself? you will have at least one buyer!
Thinking on making it smaller I tear down one cheap smartphone 10X zoom (in the attached picture), but there are many other optics parts I couldnt find yet to buy in ZnSe
(https://img.techpowerup.org/200603/telescope.jpg)
Cheers!
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maybe here https://www.cdysgd.com/list-15-1.html (https://www.cdysgd.com/list-15-1.html)
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Hi Dav, I haven't purely hobby projects haha!
That should work but you have some issues to overcome. The FL of these lenses is not usual for optical imaging. The shell there might be too small. The optics I made were designed around the lenses, not the other way around. This is a simple refractor telescope, which works, mostly.
I'm looking to upgrade the front element of this one I've made to 58mm ZnSe lens and possibly use some other small elements to better the design.
If you do ever want to look at getting some parts printed and mailed, I'd happily look to help you.
Cheers again and keep my updated with how you get on. I plan to start work on my thermal scope v2 very soon!
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Thanks Niall will let you know, will keep researching and once I have the optics testing, looking forward your v2 8)
Maybe worht also looking at other materials like NaCl KCl CaF2 Ge KRS-5 BaF2 or CdTe
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Indeed, there are definitely other materials that can be used. ZnSe is nice because it has decent transmittance and still allows visible light through for setting up and testing.