While chopping up CD’s (with branch-cutting shears) for a mosaic, I inadvertently split one into a thinner mirrored surface. I noticed that I was still alive by the misty condensation that spread across its surface from my breath, but also how the mist cleared as it evaporated, not just from the edges but from where a warm fingertip pressed on the plastic from behind. In fact with less exhaling, the opaque mist didn’t even appear on the warmer spot, and I immediately applied this discovery to a hafbakery idea as we are wont to do.
By taking a thin metal or plastic surface with a mirrored or non-reflective backing and covering its back with a matrix of tiny elements that can quickly change temperature a few degrees, one could create a display for moving pictures. At the bottom would be a wide blower of moist air - visible steam would not be necessary.
Computer control of the temperature spots could result in dreamy depictions of winter landscapes, ghosts and goblins or changing cloud formations, or hands-on viewer interaction could create fleeting finger paintings – surely more exciting than CD mosaics.-- FarmerJohn, Jun 16 2004 Liquid crystal sheet http://www.edmundop....cfm?productID=1642Bad for winter landscapes, but makes many colors. [kbecker]cj finn's link http://www.clearmirror.combathroom mirror defogger heats entire mirror [kbecker, Oct 04 2004, last modified Oct 21 2004] cj finn's link http://www.clearmirror.combathroom mirror defogger heats entire mirror [FarmerJohn, Oct 04 2004, last modified Oct 05 2004] Breathtaking brilliance.+-- cromagnon, Jun 16 2004 genius! *rapidly taps fore head with index finger*-- etherman, Jun 16 2004 I seem to recall a sci fantasy story where an image formed in the mist of a breath on a mirror - I guess the witch or wizard in question was using one of your devices. Croissant!
But given that breath mist will also form on cold windows, and modern liquid crystal technology allows for transparent circuits, how about doing this with windows too?-- DrCurry, Jun 16 2004 You're not really a farmer, are you?-- lemon tetra, Jun 16 2004 Nix.-- FarmerJohn, Jun 16 2004 I like it. [+].-- Apache, Jun 16 2004 Could it work so that my face was mirrored, surrounded by constantly changing hair, eyebrows, beards etc? I'd like that.
Misty mirror on the wall, who's the smartest of them all? Why.... it's that Farmer John, of course.-- Fishrat, Jun 17 2004 Absolutely mistical.I don't understand the two negatives.-- 2 fries shy of a happy meal, Jun 17 2004 What sort of elements were you thinking of? Peltier would be easiest because they could cool as well, but little heaters would be cheaper. You would need to cool the entire surface slightly if the elements could only heat, otherwise it would quickly be too warm to work. Here is an idea, air is pulled across the back of the mirror which is covered in moist wicking, and blown onto the front surface, this cools the back, and provides moist air in one shot. Then cheap little constantan wires can be used to heat the spots where the vapor shouldn't condense. The whole thing can run off one 12V halogen transformer and a little radial fan. A little 7805 provides power for a microcontroller that generates the images. You may have to make a python script that changes all of the instances of little in this annotation to "big" if you want to make a larger version.-- brewer, Jun 17 2004 Oooh, eerie. I can just see a silent "face" peering and saying silent things. You could also add a white beard to your reflection after a shower or a pair of white glasses. +-- k_sra, Jun 17 2004 Definitely eerie. Until these become widely know, I foresee some hilarious episodes convincing your friends they've seen an ethereal spirit in the looking glass. +-- spacemoggy, Jun 17 2004 Excellent. But why...why doesn’t it tell time?-- ldischler, Jun 17 2004 It's also great on top of a bagel with cream cheese to give our bodies the aluminum and petrochemicals they crave. Ooo shimmery. +-- sartep, Jun 18 2004 superb. On a slightly tangential but related note, I recently went to Disney MGM where they do this big show called "Fantasmic". Micky is live on stage but film images are projected onto spreading sheets of misty water produced in front of him from the lake by fountains with prewsumably special nozzles to create a sheet like water stream. Resulted in being able to see the film images but also able to see through them to see what was happening on stage at same time. Brilliant. But not as good as your mirror.-- goff, Jun 18 2004 Out of the box thinking, again. Combine several layers. Each layer has coloured lighting from the side, which is normally contained by total internal reflection, except where the droplets scatter the light. Very thin sheet would be faster.-- Ling, Jun 18 2004 Interesting variation of a technology that I worked on in 1985. There I was creating pixels of clear or scattering texture in smectic liquid crystal layers by using a small heater (current passed through a transparent conductor [Indium/Tin Oxide] layer on the back of the glass cell) to sequentially heat rows, then applying a voltage to orthogonal column electrodes on the opposite side of the cell to 'fix' the texture as the liquid crystal layer cooled though its transition temperature. I built a prototype that had 8 rows and 8 columns and could display characters (at least one at a time). Mine was then projected using an optical system to make a usable projection display (my 8x8 display element was only about 3mm square). The key problems are indeed 1) To keep the thing cool enough to allow the heaters to cross the transition of the display material (in this case evaporating water). I used compresed air. 2) To address rows and colums fast enough to make a usable display for moving images. I needed around 20mS per row, which would mean that today's 'typical' XGA screen resolution could only be refreshed once every 15 seconds - hardly gripping for action movies.
It did make a really high contrast ratio display since the layer scatters light very well. The other 'problem' was that there is lots of existing prior art in this area for display technologies, so it's hard to craft a patent to avoid it.-- ATP, Jun 18 2004 Great idea. Unfortunately, its already baked. I could use one though. http://www.clearmirror.com/-- cj finn, Jun 18 2004 Hmm... *scratching head in thought* ..............brilliant!!!! Croissant for you!-- kranedawg, Jun 18 2004 The clearmirror.com link is nothing like the idea described. cj finn, I suggest you reread the idea.-- waugsqueke, Jun 18 2004 random, halfbakery