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The reason why I ask is because I'm a bit concerned after reading an article on Infrared light and the potential damage it can do to the eyes. These are the articles I was reading:

http://tuxmobil.org/Infrared-HOWTO/infr ... afety.html

http://en.wikipedia.org/wiki/Laser_safety

Thanks

Earl

The trackIR operates by tracking reflected or emitted IR light that is imaged by a CMOS sensor. The sensor and emitters are tuned to 880nm, slightly above the visible spectrum, you can see them emit a slight glow when the room lights are off, this is the very upper end of the red spectrum. The sensor and IR LEDs are covered by a very special plastic that we custom designed with Bayer to block all light below 820nm, it passes all light above this point, it is called a band pass filter.

The LEDs emit at 880nm and are standard off the shelf IR LEDs, we run them all the time with the unit is turned on. There are 4 of them and they each have a total radiant output of about 23mw/sr, that is 23miliwats per ster radian. Total output power is NOT 4 X 23 mw/sr as the LEDS do not overlap exactly, they create a coverage pattern with slight overlap at the edges. Also, the LEDs to not emit a uniform brightness, they have an angle to half intensity, so the center of the overlapping LEDs is the SAME brightness as the center of each LEDs output, hope that makes sense.

Your eyes ARE sensitive to IR light, you can�t see it, but your eyes will register the �power� of the light, your pupils will shrink down as if you were looking at light in the visible spectrum. Remember, we are just slightly above red in the visible spectrum. You won�t feel your pupils getting smaller when our device turns on because we are a relatively low level of light for an average room condition. If you turn out all the lights in the room, put the unit about 1 foot away from your face and watch your eyes in a mirror, you will see your pupils contract, they are �seeing� the IR light.

As for the amount of power the LEDs output, it is many of times lower than simply going outside, not to mention on a bright sunny day. As I had seen posted before, we are a small fraction of the IR output from a normal incandescent light bulb. ANSI references spec ANSI Z 136.1 � 2000 for laser power emission, but we are not a laser, so in the back of the spec they reference ANSI/IESNA RP-27.1-96, which is the spec for lamp output, basically what we are and what ANSI says to use. Maximum exposure for our wavelength range, which is from 700nm to 1100nm is 10mw/cm2. To convert our power output, which is about 30mw/sr, we apply sr x 1cm2/distance2. Typical user distance is 18� or about 45cm (on the conservative side, most users are further away), so 30mw/2025 = .015mw/cm2. Needless to say, we are on the safe side!

Thanks for the info. I feel much better about it now. Unfortunately, the unit has stopped working. The unit isn't responding at all. I've even tried reinstalling windows and its not helping. Any ideas what I should do?
Thanks

Earl

Contact us directly, Support@NaturalPoint.com, with the following info.............

What is the Serial # of the device?
It should be located on the end of the cable, near the USB plug, or on the underside of the device.

Could you send us a copy of the Setupapi.log file?
It should be located in the C:\Windows folder

Have you tried the device on another system?

Are you plugging in directly to the system, or are you using a hub?

Have you tried isolating the device on the USB ports?

Could you attach a screen shot of your device manager, and tracking screen?

To make Print Screen work, you must save an image of what's displayed on-screen to the clipboard and then paste it into a document where it can be printed.

Windows Help: Print Screen

To do this, follow this procedure:

1. Maximize the window you'd like to capture.
2. To copy/capture the current window, hold down ALT + Print Scrn at the same time. To capture the entire screen, just press Print Scrn alone.
3. Open a new document in MS Paint, MS Word, MS Photo Editor, or Adobe PhotoShop.
4. Paste the screen shot by holding down CTRL and V at the same time.
5. Save the document as a .JPG or .JPEG file and send it in.