NUI Group - Open Source Interface

IR LED Strips from Environmental Lights are a joke

2010-03-19T19:49:34-05:00

I am seriously let down by these led strips. They really don’t cast any IR unless they’re 6 inches from the surface. They don’t even shine through acrylic to the camera - even my IR tv remote can do that.

How can these possibly be weaker than a tv remote?!?!? WHY MAKE THEM???

Which u profile for IR-LEDs

2010-03-19T11:59:47-05:00

Hello!

I bought the LED ribbon of peauproductions.com:
8mm Infrared LED 5 Meter Reel - 850nm

Now I have to choose a “u profile” where I put the ribbon into for my FTIR wall 1,2m x 0,9m.
I have to choose one of these materials:
- Aluminium
- brass
- stainless chromium steel
- bright steel / black steel

Which one will be best?

And the width of the profile? 8mm is the ribbon and the acrylic. Should I buy 8mm or more (9-10mm)?
And what about the height? What distance should be between the acrylic and LEDs for my FTIR wall system?
(because of the wall I have to put spacers between the led ribbon and the acrylic, so the acrylic plate won’t crash the leds )

Best Regards PHANTOMIAS

AIXIZ Q&A AREA

2009-12-04T09:33:31-05:00

Hi all, Chuck Here from AixiZ.

I thought it would be useful if I posted here to help directly with any questions regarding the AixiZ laser products you are using.

My direct email as well is

Another laser brightness question

2010-03-17T09:48:54-05:00

Just getting to the laser focus/alignment stage, and like many folks we are having problems. Here are the details of what we’ve got so far:

- 50 x 64 inch glass surface, so it’s on the large-ish side
- 4 x 850nm 10mw lasers with 120º line generator lenses from Aixiz, ridges toward the diode, (the other way made blurry lines)
- Modded (ir filter removed) and assembled ps3 eye with 850nm bandpass filter from Peau, m12 adapter and lens
- Mini ATX power supply, running all 4 lasers in parallel off the 5v line. Seems to be sufficient wattage/amperage according to the spec
- CCV 1.2, Mac OS X 10.5.8 (tried Macam as well)

Our problem right now is we can’t even get any IR coming through our Rosco, and the touch illumination is really faint. So I’m assuming our light plane is too weak right now.

I’ve focused the lasers pretty well by starting with the dot lens, getting a nice point then attaching the line lenses. The lines I’m seeing are nice and thin, but do they seem to be weak. Looking at the camera output they aren’t super bright, and they seem to dim as you look left or right of center in the plane, as well as getting pretty dim after about 30 inches.

I’ve seen plenty of nice bright planes from other users, so I’m assuming it’s either a power supply problem or a camera problem, (with a very slim chance it’s a camera setting problem?) Any advice would be super greatly appreciated.

IR illumination for DI

2010-03-16T12:29:21-05:00

hey! I’m new to the forum, so sorry I’m making any dumb question. Sorry in advanced if my english isn’t good, but I’m Portuguese.

So i got this forum while searching how to DIY a multitouch table. I stardet doing a MTmini but i wanted to interact directly with the image so i started researching a bit and i found that there were two types of MT : FTIR and DI, I was planning on making the FTIR but i couldn’t find the compliant surfaces, plus, i want to try and work with fiducial so i went for a DI.

gathered some materials but i’m finding hard to get the ilumination i need. I found some 850nM IR illuminators on ebay, that were cheap, but i don’t know how many will i need… besides, ebay orders take centuries to get here.

other thing is, if i get illuminator, do you think i should get a complete one like this
or just these. are these last easy to connect?

other question is, is there a cheaper/realiable solution for IR ilumination

sorry if i’m asking too many questions but i’m really new to this

better/cheap IR filter?

2010-02-05T17:20:23-05:00

hi,

I have been reading up on IR filters for a while now, I know of the main applications commonly used here. I am under the impression that the “negative film” or “floppy disk” filter produces less than ideal results and “proper bandpass filters” are the best choice but are quite costly.

I think I have found a filter that exists somewhere in between these two extremes, basically looking for comments/suggestions from you guys:

The IR filter is a 4x4 inch, polyester filter for use in photographic lighting: ‘Gel Snap Holders’

According to the company “Light Transmission begins above 740 nanometers for the 87 model”

At $27 for 100 x 100mm sheet this may be a good buy or am I missing something?

here’s an image of the wavelength characteristics of the various ‘models’ available:

EDIT: Sorry Moderators, I just realised that this is in the wrong section, my bad

LEDs at 950nm

2010-03-15T10:44:25-05:00

Hi,

I have been working on my first FTIR table, just a small project to work out the process. I just got the table up and runnign and find that my blobs are weak. I bought the hardware a year ago in hopes to build a table then but shelfed it. After getting weak blobs I went over the specs of my LEDs and
Wavelength: 950 nm

Beam Angle: +/- 25

Radiant Intensity: 310 mW or sr

Maximum Forward Voltage per Color: 3 V

Maximum Forward Current: 100 mA

Maximum Power Dissipation: 210 mW

By these specs I should have strong blobs right? Anyways, I am using a slice of magnetic ribbon from a old floppy, some say this is possibly the worst filter and now noticing that the Wavelength is out of the recomended spectrum I wonder,
should I replace LEDs for a more suitable wavelenght?
or is this a filter issue?

Thanks for the help

Mark

Laser mount - yet another one ;o)

2010-02-27T08:56:36-05:00

This is as simple as I can come up with - still to be finished…

Glue the whole lot to the bottom of the acrylic sheet. Turn the nuts to adjust height/angle. The slot in the main sheet is enough to stop lateral movement - using 10mm acrylic.

Can i use IR LED 880nm?

2010-03-13T06:13:56-05:00

Hi all,
Can i use IR LED 880 except 850?
thanks and best regard

LED IR 850

2010-03-13T07:12:38-05:00

Hi,
Can i use LED IR 850nm and 25 deg ?

thanks