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Superresolution Total Internal Reflection 3D Printer

Use evanescent waves to polymerize resin at much finer z resolution
  [vote for,

To my surprise, LCD display panels can be made staggeringly thin. 0.3mm is the state of the art at the moment, but many incentives are aligned to push that further. This is so thin, that you could do microscopy THROUGH it. One type of microscopy is TIRF <link> which works by shining light at the critical angle at of the glass so that it reflects (Total Internal Reflection). Here, a weird thing happens, as the light reflects inside the glass, an evanescent wave appears on the top surface that behaves like the light but only extends for around 200nm* or so.

Now, there are 3D printers that use LCD screens, see my other idea <link>. This suggests that we can replace the backlight with a one that is configured for TIR. There are a few ways of doing this, you could create a light sheet <link> and scan across at the critical angle of the screen/resin interface. You could possibly make a grid of lenses to create the critical angle, or maybe even simple angled LEDs. It doesn't need to be good enough to image through, like microscopy, and it doesn't even need to be completely even, we're only polymerizing resin.

So, our screen has the image of the first layer of the object we're building. The TIR light is turned on, a 200nm layer of resin polymerizes, the platform then moves up 200nm and we repeat until our astonishingly precise object is printed. How precise is it? well, the current 3D printers of this type print in ~200um steps, so this is 1000x better. So good in fact that the z-axis steps will be difficult to control at that level, we may even need laser interferometry to get enough control precision.

The downside? well, if each z step is now 1000x smaller, it will take 1000x as long to finish the print, so an object that takes 6hrs to print in current machines will now take the best part of a year, exactly what the world of rapid protoyping needs.

* if you thought 0.3mm was a small distance, nanometers are really small.

bs0u0155, Dec 30 2020

TIRF microscopy https://en.wikipedi...rescence_microscope
[bs0u0155, Dec 30 2020]

Evanescent Field https://en.wikipedi...ki/Evanescent_field
[bs0u0155, Dec 30 2020]

Total Internal Reflection https://en.wikipedi...internal_reflection
[bs0u0155, Dec 30 2020]

Light Sheet https://en.wikipedi...rescence_microscopy
[bs0u0155, Dec 30 2020]

Laser, LCD mask and DPL https://www.matter-...based-sla-printers/
I just not seeing, getting the amount light out of evanscent wave when it is a fraction of the source. [wjt, Jan 05 2021]


       Scientists will love you.   

       You've also invented the: if you can see it through the eyepiece you can embed the single cell or virus in a preservative polymer 200 nM thick coat to make a kind of slide.   

       At 200nm (or 100 nM) you can 3D print a diffraction grating, waveguides, many MEMs devices, and other very small things without an IC fab, But if you do have an IC fab you can make a big wafer of something, load it into an evanescent wave 3D printer and put a layer of what might be called "optical bench on a chip"[link] components made with your evanescent wave 3D printer.   

       This would benefit optoelectronics. as 3D printing optical elements at 200 nM with resin sounds pretty affordable Monitor screens would benefit.   

       Also a nifty thing for your idea is that while others might print imitation fabric(?) which is a lot like chain mail with their 3D printers you 200nM is so small you can print real fabric, or maybe more importantly, completely new kinds of (better) thread:   

       Visualize your LCD screen curled around so it resembles an inner-lit paper towel tube; then use evanescent waves to print some resin; it can of course be nanomail, but the general idea is that it is getting pulled (vacuum or airjet fiber draw) out of the tube where it becomes thread, then they can make things out of the nanotextured thread.   

       Paper towel tube evanescent wave 3D printing could also be used to print replacement arteries and veins; As each layer of a reverse-jawbreaker 10,000 layer is printed on the inside of the LCD tube, it can have a different chemical makeup that makes it more biocompatible than previous attempts at synthetic vessels; It's really primitive, but if each alternating layer is a polymer with either + or - surface charge, and each of 10,000 layers takes 144 hours to wear off, revealing the layer beneath it, then you have 18 decades of very fresh, non-plaque bearing vessel surface you have printed. You might do lots better than that: a 2020 artificial heart inner surface lasts 4+ years.   

       Printing out artificial blood vessels that reveal a fresh new (highest known quality) interior once every 144 hours might be much more rapid than necessary.   

       Also, because you are printing with the resin and weave/wallpaper pattern of your choice, and each layer (and LCD pixel) can have its own resin laced with physiochemicals, you can make it so that a drug completely harmless to humans, like a rare plastic-degrading enzyme (polylacticacid-ase to be silly; PLA) could be given to the humans if they wanted to purposefully scrub out a single layer of their new artificial blood vessels. This could also keep the artificial blood vessels clean, clot minimized, and plaque minimized.   

       So, is evanescent wave 3D printing good enough to print an artificial heart interior lining 10,000 layers, 180-1800 years fresh and clean? It could be. I have an image in my mind of 3D printing not with a flat LCD and a flat "top base" but a specially-made curved LCD and curved pull-up-top, sort of like two spoons nesting together. That is because rather than assuming you are going to print granules together in a heap, you can print layers of textured film on a form without any dislocations, "edge steps" etc. Then you clamshell the two halves together. Or, since I have no Idea, you just print the whole heart, using a noncontoured base; they could try both on nonhuman mammals first and find out if the stair-steppy artificial heart if as good as the smooth film artificial heart   

       Could you make a (dip 10,000) times artificial heart this way without a 3D printer? possibly.   

       Other applications:   

       [bs0u0155]'s evanescent wave 3d printer could be an evanescent wave 3d Printer; but it could be a 3D evanescent wave materials science and other technology/biology tool:   

       If you were willing, you could grow stochastic crystals, purposeful crystals, or investigate chromatographized / electrophoresized crystals from samples.   

       What if you 3D print, not a blob of resin, but a "aqualet" of a chemical onto a IC fab silicon trough array \_/\_/ If you grow a crystal in the trough, based on say a 1/100th fluid concentration drying out you get a sample laying right on it's own IC test bed.   

       Like maybe the base of the well/trough is a camera element transistor(spectroscopy-like), or is connected to a data line for capacitance testing, or has a laser diode underneath it, or has a grating of conductors ||||||| the crystal lays on, and various voltages can be applied and effects listened for. With an under-trough _))))))_ nanoheating element, melting point could be determined for the crystal. Printing 200 Nanometer liquid blobs is great for technology and screening new materials, particularly if you print them on some kind of pan-functional IC chip base. So basically you would get like a 100-300 mm wafer with pan-fuctional capabilities then print trillions of samples onto its wells.   

       Who doesn't want to use a 300mm wafer with (90?) trillion little wells in it to test 10 trillion chemicals, 9 times each for unusual properties. I remember when ytterbium copper superconductors came out. It just seems like it would be great to screen a library of variations, well, with 200 nm 3d printing (on 2 axis) you can do things like screen a ten trillion materials science YbCu samples on a wafer.   

       Thinking of when people have companion robots, as a home device, it could be used for robot repair. One application is printing electrically guideable supplemental or replacement sensor arrays, or making smart car wax. You print out tiny flakes, each is an electrical circuit, the car wax keeps it on the surface of the car/robot and other existing sensors (visual light, UV/IR) on the robot or car read the sensor-wax. Perhaps the individual 11 micrometer or smaller circuits (which were drawn 200 nM thick in the z axis) made from things like conductive PEDOT polymer make the wax sparkle slightly; You can also print out RAIC (plaid conductor, .5b) and put a layer of that on between wax coats. The robot, without much effort, is then able to print both its spare sensor, surface, and some ability parts.   

       Can you figure out how to get the resolution of your 3D printer's evanescent wave to be about 10 nanometers? You could do amazing things then like directly print geometry-drugs (stuff- glomming antibody mimics)   

       One possibility to increase he resolution even higher is Fourier-like waveform stacking, (wave addition) so instead of what I perceive an un- engineered evanescent wave looks like, that is, a decaying harmonic oscillator sinusoidal wave,   

       It could look like some other wave but have an evanescent wave's nanodepth. It could be like a big tall blob without much spread (I think they call that chirped light), or a soliton, or Even something like waves-cancel waves active noise cancellation.   

       With active noise cancellation wave physics, the evanescent wave instead of looking like a short range squiggle, looks like a chopped 1/10th of it's non- flatline- after- noise- cancellation- squiggle, so like 100%-1/10th as big, 100% near to 10 times further away, producing higher resolution.   

       People who know stuff about optics would know what would happen, but another way to make the evanescent wave even tinier/shallower would be to put an object in front of it. 500 picometer-3nm quantum dots are published, and it you put a shape made of those in front of the light exit surface (like maybe even have them embedded in the glass/polymer) a 200 nM wave that has to pass a [::] 500 pm dot array might act really different, depending on where you put the dots. I'm clueless but this is likely "post refractive" so although I want to say "fresnel", that might be meaningless, those big things you see on 2 screen doors on top of each other "emergent macropatterns of Moire" might arise from putting 500 pM dots in front of a 200 nm evanescent wave   

       Also, with 500 pM dots in front of a 200 nm evanescent wave that is like a 400 x 400 matrix dotspace in front of each 3D printed evanescent wave pixel. I'm imaging this really crude physically changeable viewmaster slide kind of thing /contact print sheet array that occludes say 100 different patterns like (all left, all right, asterisk, top half, bottom half,) Sort of like the ASCII block characters people use for drawing at the viewmaster slide made of quantum dots;   

       You could build microfluidics devices and MEMs devices with it.   

       Other thoughts and words: Biochem protein crystallization, chromotography, 3D print what microfluidically comes out of a chromatography column or electrophoresis "column" into IC \_/\_/ troughs at microdilution, crystallize each; auto-scan with published 5 nanometer microscope; you've characterized a million or a billion chemicals from one biological or plant sample   

       That's great!
beanangel, Dec 31 2020

       Whoa up there. A two questions.   

       Can Evanescence be pixelated enough to get the correct plane slice light pattern needed for resin printing? I can believe, at the nano scale, evanescence can be used in a holistically way but to specifically pattern at that scale might to need a structure which seems to me a bit catch twenty two.   

       Also, are the clever resin/oxygen reactions even compatible with evanescent waves? Energy delivery , setting and not specifically setting of the resin.   

       Since the direction matters a wave traveling across the face of the slice won't work. A plane of pixelated tiny Evanescent burst lights aren't going to get to the 200nm scale.
wjt, Jan 03 2021

       How is the top surface of a blood vessel going to wear away if it's protected by a layer of plaque?
Voice, Jan 03 2021

       Once every 72 hours or 2 months you could take an enzyme pill, that says to the outermost fluid facing vascular/artificial heart coating layer, "dissolve".
beanangel, Jan 04 2021

       Illumination is not the same as setting off a reaction. LCD masks burn out due to the amount of light used.   

       True, it only takes one photon to move the electron but which one.
wjt, Jan 05 2021


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