Hey Ben, I've got a question regarding photo-resistive film, since you've been using it a lot in your projects from what i recall.
The basic question is how thick is a layer of such film, and what is the maximum thickness you can get from a single layer?
Now to expand a little upon the question: I was wondering if its possible to reproduce a fingerprint from a fingerprint scan without the use of a high quality 3D printer. The plan was to use a somewhat high quality laser or maybe inkjet printer to print the image of the scanned fingerprint, and then expose a layer of photoresistive film to it, develop it, etch it and apply a new layer on top of it and repeat the process. The idea would be to get a sort of mold of the fingerprint while the needed accuracy is about 0.075-0.1mm detail, problem is i don't really know how photoresistive film behaves. (an alternative would possibly be to apply new layers of copper with a pre-applied film on it and just do it in a controlled temperature environment). After having a mold producing a copy of the fingerprint using silicon or gelatin isn't hard.
The overall idea of the project is to demonstrate a security hole in the upcoming implementation of a biometric database by the government where i live, where basically a cheap and easy to make copy of anyone's fingerprint can be produced at home.
Hi! I am not sure if my youtube comment actually got posted or not so i am also asking here. I want to do the freeze-drying as an experiment in school and i would like to ask some questions about how your experiment went. Is that okay with you? Thanks in advance!
Alex, in the semiconductor industry "thin" photoresist is usually 1 micron thick, or less, eg 800nm. "Thick" photoresist is maybe 3-4 micron thick. The thickness is controlled by the photoresist's viscosity and spin-coat speed. You can apply multiple layers to build up thickness, theoretically without bound. Check this out: http://istouchidhackedyet.com/
This vendors sells smaller bottles: http://www.alibaba.com/product-gs/1458702385/Nematic_liquid_cristal.html I have not purchased small quantities of LC on Alibaba, so I couldn't say for sure how this will work.
Do you think it would be possible to make switchable privacy glass like http://smarttint.com/ does? I would like some but I don't want to spend a whole $80 for one square foot.
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ReplyDeleteHey Ben,
ReplyDeleteI've got a question regarding photo-resistive film, since you've been using it a lot in your projects from what i recall.
The basic question is how thick is a layer of such film, and what is the maximum thickness you can get from a single layer?
Now to expand a little upon the question:
I was wondering if its possible to reproduce a fingerprint from a fingerprint scan without the use of a high quality 3D printer.
The plan was to use a somewhat high quality laser or maybe inkjet printer to print the image of the scanned fingerprint, and then expose a layer of photoresistive film to it, develop it, etch it and apply a new layer on top of it and repeat the process.
The idea would be to get a sort of mold of the fingerprint while the needed accuracy is about 0.075-0.1mm detail, problem is i don't really know how photoresistive film behaves. (an alternative would possibly be to apply new layers of copper with a pre-applied film on it and just do it in a controlled temperature environment).
After having a mold producing a copy of the fingerprint using silicon or gelatin isn't hard.
The overall idea of the project is to demonstrate a security hole in the upcoming implementation of a biometric database by the government where i live, where basically a cheap and easy to make copy of anyone's fingerprint can be produced at home.
Hi! I am not sure if my youtube comment actually got posted or not so i am also asking here.
ReplyDeleteI want to do the freeze-drying as an experiment in school and i would like to ask some questions about how your experiment went. Is that okay with you? Thanks in advance!
Alex, in the semiconductor industry "thin" photoresist is usually 1 micron thick, or less, eg 800nm. "Thick" photoresist is maybe 3-4 micron thick. The thickness is controlled by the photoresist's viscosity and spin-coat speed. You can apply multiple layers to build up thickness, theoretically without bound. Check this out: http://istouchidhackedyet.com/
ReplyDeleteRailon, please ask your question publicly (G+, blog, youtube), so that everyone can benefit from the conversation.
ReplyDeleteIs it possible to buy 1..10 grams of liquid crystal? Minimum order on Alibaba is 1 kg or more.
ReplyDeleteThis vendors sells smaller bottles: http://www.alibaba.com/product-gs/1458702385/Nematic_liquid_cristal.html I have not purchased small quantities of LC on Alibaba, so I couldn't say for sure how this will work.
ReplyDeleteDo you think it would be possible to make switchable privacy glass like http://smarttint.com/ does? I would like some but I don't want to spend a whole $80 for one square foot.
ReplyDeleteThis LCD is not sealed at the edges. Is it possible to seal it completely like industrial LCDs?
ReplyDeleteFantastic!!! Thanks!!!!
ReplyDeletenice work!!!, could you please do a more detailed instruction, it will be fantastic!! :D
ReplyDeleteAre you spin coating with PVA before rubbing like in this lab http://education.mrsec.wisc.edu/nanolab/LCD/ ?
ReplyDeletehttps://www.alibaba.com/product-detail/china-manufacturer-Nematic-liquid-cristal-smart_1458675165.html
ReplyDeleteIs this liquid crystal suitable for LCDs?
A while ago you showed us how to make LCD and working principle. can you please also make few videos on electrophoretic display?
ReplyDelete