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Dry erase board lined with IR sensors to record pen strokes [video]

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Re: Dry erase board lined with IR sensors to record pen strokes [video]

#11

Post by arey_abhishek »

langseth wrote: post #9

Is this working on a similar system to Optical touchscreen technology? Did you build the ir sensors into the edge of the glass or at the surface? http://www.planar.com/media/111012/touch_technologies_white_...

Different technology. This is what we've used: http://www.touchscreen-me.com/technologies-comparison-infrar... Same result can be achieved with CMOS sensors mounted on the corners as well but ambient lighting conditions affect the way the board works.

Re: Dry erase board lined with IR sensors to record pen strokes [video]

#12

Post by arey_abhishek »

djrogers wrote: post #4
ohitsdom wrote: post #3

Really impressive. Must be pretty sensitive IR sensors to not have false detections when the marker/eraser gets close to the board but doesn't touch it. Any info on the hardware and software stack?

Looks like it did actually have an FP+ on the eraser there if you compare the phone to what he actually erased onscreen. I'll second the request for more info though!

The eraser did actually touch the board, but appears like it didn't because of the reflective surface. :)

Re: Dry erase board lined with IR sensors to record pen strokes [video]

#16

Post by jwcacces »

My high school had these in 1995. Each marker color had a different reflective pattern on a band around the tip so the scanning laser could read it like a bar code. I remember the eraser having a solid reflective band all the way around. It was pretty cool, as we all got whiteboard "transcripts" emailed to us at the end of the class that you could play back / pause / rewind / etc... whenever you wanted.

Also, these boards had no projectors (they used real ink in the markers) and didn't require special markers (just the barcoded pen collars, which were removable)

Re: Dry erase board lined with IR sensors to record pen strokes [video]

#17

Post by pavel_lishin »

raldi wrote: post #14

This is cool as a DIY project, but digital whiteboards have been around since at least 1991: https://en.wikipedia.org/wiki/Smart_Board

The one at my high school (admittedly, over a decade ago) was ridiculously expensive, though. If this is cheap, it could be pretty great for a cash-strapped startup, striking the balance between a smart board and a person with a cellphone snapping photos.

(The expensiveness of the whiteboard made it even funnier when a teacher used a Sharpie permanent marker on it one day.)

Re: Dry erase board lined with IR sensors to record pen strokes [video]

#19

Post by arey_abhishek »

raldi wrote: post #14

This is cool as a DIY project, but digital whiteboards have been around since at least 1991: https://en.wikipedia.org/wiki/Smart_Board

All the previous whiteboards force you to buy a projector or invest in smart pens. This costs ~150USD to make vs. 1500USD+ for the kind of smart boards that existed in the past.

Re: Dry erase board lined with IR sensors to record pen strokes [video]

#20

Post by raldi »

arey_abhishek wrote: post #19
raldi wrote: post #14

This is cool as a DIY project, but digital whiteboards have been around since at least 1991: https://en.wikipedia.org/wiki/Smart_Board

All the previous whiteboards force you to buy a projector or invest in smart pens. This costs ~150USD to make vs. 1500USD+ for the kind of smart boards that existed in the past.

Ah, this is a key piece of information, and indeed sounds like quite a big deal.

You should mention it in your presentation!

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