apuntes sobre materiales inteligentes
Intelligent Materials According to Bullinger (2007, p. 36), intelligent (or smart) materials have the capability to react to stimuli from the environment or changes there and to adapt their functionality respectively. This is either directly possible or achieved through combining sensory materials with actuating materials and a control unit. The resulting combination is named composite material and has special properties. Until now intelligent materials can be classified – according to the main effect they use or expose – in at least five groups:
• with shape memory; • with piezoelectric effect; • with electrostriction or magnetostriction; • using electro-rheology and magneto-rheology; • using chromogenic effect.
Speculating on further development, one could expect materials with programmable (or computer-controlled) behaviour (e.g., remote form giving?) in the (near) future.
link to hacks
Originally Posted by Tinman View Post
Yes, you can use ANY good quality polarizer as long as it fits and you rotate it for optimal result. I did this a long time ago on an old Sony LCD projector with a bad blue polarizer. As is typical, that part is never available. Would be too easy, right?
Well, this was a dumpster find anyway, so I took a plastic polarizer from a calculator and cut it to size and stuffed it in there. With the projector on, I rotated the polarizer until I got the best "black". Taped the damn thing in place and used the projector for quite a while before I upgraded to a CRT.
It worked just fine. Using a glass polarizer would be better, but any GOOD polarizer will indeed work just fine. The polarizer doesn't make the color. The Dichroic mirrors in the light path do.
It's not rocket science at all. The manufacturers just like to make it difficult, so we just buy a new product.
The dicronic lens and mirrors are part of the color separation process but there ARE different colored Polarizers. The one I'm guessing you are looking for is the yellow colored one that blocks the most UV light. Its generally the one that cooks followed by the LCD Panel itself. if you can get one that blocks the path of the light before the panel it doesn't really matter what shape it is .. You will need one made of glass since the plastic ones will cook. You can fool around with one from a cheap pair of UV blocking (sunblockers type) sunglasses that you pick up for cheap at a dollar type store. The ones that the projector makers use are generally fitted to the projectors light path. but if you can get one off another projector as long as you get it to block the light between the light path and the actual panel you should be good to go. If you can get one made out of Glass and can cut it down without cracking it. Make sure to put the coated part of the glass polarize facing the LCD panel.
BTW If you are just using the projector for data you can swap out a panel and polarozer from a matching projector that has the same style panels and polarizers in it but you will not get accurate colors like you would with factory panels. For example If you take two matching projectors that have burnt out blue panels which is common you can replace the Blue ones with green or red panels and polarizers and you will get a decent picture. its best to start with the green panel. I'm pretty sure since you have the yellow spot already you will also have replace the LCD panel.