Roller Venetians consist of a set of parallel Perspex roller tubes, spanning the width of the frame, all touching each other top and bottom, so that if the top or bottom one is turned, the rotation is transmitted all the way up or down through the entire structure.
One half of each individual Perspex roller is obscured by being a solid colour, and the other half is clear. This means that when fully rotated into one position, this blind provides for a total black out. The slightest turning of the blind allows for parallel slivers of light to enter.
Now that you understand the principle of Roller Venetians, you have to consider the opportunities these blinds present if the rollers are capable of first of all being motorised, and secondly divided into a large number of segments running across the width of the frame, then down its length.
At any one time the blind can be set to provide total darkness, but with the motors turning the vertical rows numerous pattern and colour variations can be created that are constantly changing.
Complex? - slightly. Usefulness - dubious, but entertaining, and unlike most blinds provides for 100% black out, without needing to be raised to allow controlled amounts of light to enter-- xenzag, Jan 12 2012 Adjacent rollers must be able to roll in opposite directions, else you will have gaps between them (OR you will have friction between them that prevents rolling).-- Vernon, Jan 13 2012 You're so knowledgeable Vernon. I might never have known that. Beyond that there are systems of rollers that turn in the same direction in order to create the very friction effect you have just discovered. These are called "Shearing Rollers" - or sometimes "Friction Rollers".-- xenzag, Jan 13 2012 Can they be used as a mangle, in case you have any clothes which need drying?-- hippo, Jan 13 2012 Good idea.... especially for socks.-- xenzag, Jan 13 2012 There was a similar idea here, using rotating, partly transparent columns to control light admission. They were to be built into a wall, rather than in the form of blinds.
To allow closer to full transparency, the opaque part could be a strip through the middle, thus: Ø, rather than one half of the roller.-- spidermother, Jan 13 2012 //Ø, rather than one half of the roller// That's an excellent idea. I was trying to work out the greatest "dynamic range" you could get with stripes on the surface, but the Ø is much better.
One query: how do you ensure that all the rollers stay in synch? They'd have to be geared to stay locked in relative position. Or - wait!! - magnets!! Magnets make everything better.-- MaxwellBuchanan, Jan 13 2012 An excellently over-engineered solution, xenzag. Have a bun.-- DrBob, Jan 13 2012 Magnets! Smoke! Mirrors! As regards rollers if there were two sets placed in front of each other, then polarsing lenses could be deployed. One set part vertical, and one set part horizontal. Combined with colour and alignment, makes for even more permutations.-- xenzag, Jan 13 2012 You had me at socks. [+]-- Grogster, Jan 13 2012 //polarsing lenses// It's what Pole Pants were invented for! [later] A thought occurs! Why not do away with the window pane altogether. Construct the blinds from dozens of glass rollers and each roller can be made up of several different colours of glass. DIY stained glass windows!-- DrBob, Jan 13 2012 Will the cylinders have those little pins sticking out of them, as in cheap musical boxes, so that they play a tune when being rolled up or down?-- hippo, Jan 13 2012 Actually "Roller Venetians" sounds like it should be a modern "Starlight Express"-style musical version of "The Merchant of Venice".-- hippo, Jan 13 2012 Ha - that would be the Vene-tune variation :-)-- xenzag, Jan 13 2012 random, halfbakery