I've seen a gizmo consisting of a vertical line of red LEDs which appear to flicker slightly when looking right at it=2E At first I didn't understand what it was, but as I turned my head, the word "ABSOLUT" spelled out in the air (this was in a bar)=2E Very clever I say=2E If you settle for 8 LEDs, you could build one from say a 16F628 with almost no support circuitry, and use a 5 or so line PICBasic program to drive it=2E /Hugo >>-----Original Message----- >>From: Lindy=2EMayfield@EUR=2ESAS=2ECOM [mailto:Lindy=2EMayfield@EUR=2ESAS=2ECOM= ] >>Sent: Sunday, May 23, 2004 12:16 PM >>To: PICLIST@MITVMA=2EMIT=2EEDU >>Subject: Re: [PIC:] Single Row of LED's Illusion - How they do that? >> >>Thanks for the info, I'll check that out=2E >> >>Sorry, perhaps I wasn't specific about my "idea"=2E (-: I >>meant I thought I could maybe do one where you have to look >>at it and shake your head NO! over and over to read it=2E >> >>-----Original Message----- >>From: pic microcontroller discussion list >>[mailto:PICLIST@MITVMA=2EMIT=2EEDU] On Behalf Of Jinx >>Sent: Sunday, May 23, 2004 12:07 >>To: PICLIST@MITVMA=2EMIT=2EEDU >>Subject: Re: [PIC:] Single Row of LED's Illusion - How they do that? >> >>> To be more specific, I had the idea of seeing if it would work with >>> just a row of lights in one place and you have to move your head >>> to read it >> >>I don't think so, unless you have more eyes than a spider and you >>can select which one(s) is looking at the LEDs >> >>The effect is similar to how a dot matrix print-head makes characters >>with a line of pins=2E Where the pins struck the paper and made a mark >>is the record of where they were=2E LEDs "print heads" use the principle >>of persistence of vision, like a film strip or flip-book=2E >>Each frame is a >>single static picture but run quickly in succession gives the >>impression >>of a dynamic display >> >>Bob Blick's Propellor Clock is a good place to start >> >>http://www=2Ebobblick=2Ecom/techref/projects/propclock/propclock=2Ehtml >> >>Google for "propellor clock" to get other examples, or eg "message >>wand" >> >>http://www=2Esalient=2Ecom=2Eau/led_MessBar=2Ehtm >> >>-- >>http://www=2Epiclist=2Ecom hint: The PICList is archived three different >>ways=2E See http://www=2Epiclist=2Ecom/#archives for details=2E >> >>--- >>Incoming mail is certified Virus Free=2E >>Checked by AVG anti-virus system (http://www=2Egrisoft=2Ecom)=2E >>Version: 6=2E0=2E663 / Virus Database: 426 - Release Date: 4/20/2004 >> >> >>--- >>Outgoing mail is certified Virus Free=2E >>Checked by AVG anti-virus system (http://www=2Egrisoft=2Ecom)=2E >>Version: 6=2E0=2E663 / Virus Database: 426 - Release Date: 4/20/2004 >> >> >>-- >>http://www=2Epiclist=2Ecom hint: The PICList is archived three different >>ways=2E See http://www=2Epiclist=2Ecom/#archives for details=2E >> >> -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body