Archive for February, 2011
After years of working with camera-based multitouch setups, I was very interested in the newer infrared touch frames that for years had only been dual 2 touch, but were now being upgraded with software which supported many simultaneous touch points. The frames are composed of infrared LEDs, typically around 900nm and infrared sensors that are next to each other throughout all 4 sides of the frame. The previous 2 touch frames typically had one full side being LEDs or sensors, but because these new frames need to be able to detect fingers behind fingers, all the sides have both LEDs and sensors. This reduces osculation and allows multitouch tracking. There is a layer of plastic over the LEDs and sensors which is a high pass filter, blocking out all visible light from interfering with the tracking. Connection to the computer is via USB, and power is typically either supplied by the USB cable or through a separate power cord.
After researching frame pricing, available sizes, shipping prices, etc. from a few manufacturers, I decided to become a reseller for touch frames from PQ Labs. The main deciding factors were the support for both Windows and Mac operating systems and built in export to TUIO/Flash TUIO applications, which their drivers support. You can see all the different standard sizes available on the store, with custom frames also possible (contact me for custom pricing). The frames come in two forms: an overlay which includes a layer of 3mm glass, and an integration kit that comes disassembled with cheaper shipping. All frames have flat rate worldwide shipping which makes it nice because I don’t have to stock the frames and the customer is only paying for one shipping cost, directly to them from the manufacturer overseas.
I filmed a review video which you can see at the end of this post, where I go through everything from the initial unboxing to running applications. The biggest test was how ambient infrared light affected the tracking. While it’s best to just watch that portion of the video (starting at 10:42min), some interesting things about the frames can be concluded:
- The frames will work in all lighting conditions except for intense direct infrared light (such as direct sunlight)
- This means they will work outside in the shade or in any room that has ambient sunlight or incandescent bulbs
- Very large frames may have problems though with tracking towards the center in infrared lighting environments
- If the infrared light changes drastically, you may need to recalibrate the screen
The frames perform really, really well at tracking your fingers or any objects placed on the screen. Pricing and more info can be seen on the store. Contact me if you have questions.