Tobii has released a new consumer eye tracker, the Tobii Eye Tracker 4C for $150. Although I haven’t found eye tracking to be nearly as helpful as speech recognition, it is handy for those occasional situations where you just want to click a button or change context and you don’t have any command to do so (see my earlier post for details). I have been pretty happy with the Tobii EyeX, but it isn’t perfect, so I was excited to try out this new device.
It arrived just a few days after I ordered it, and came with a complementary USB extension cable. This is an essential addition if you want to use the eye tracker with a desktop, because the built-in cable is very short (although that’s nice when using with a laptop, where it reduces the bulk considerably).
The first thing you will notice after setting it up is that the lights are much less bright than the EyeX. I got used to the bright red lights, but I’m happy to not have those blaring at me all the time anymore. The new lights are primarily using infrared wavelength, although you will still see a red glow.
The main new feature that Tobii is touting is a dedicated chip for performing processing on-device. This is supposed to reduce host CPU load and makes it possible to use USB 2.0 instead of 3.0. Even though I have USB 3.0 ports, I’m happy to see this change because I have found them to be less reliable, occasionally requiring driver updates to work. Also, USB 3.0 doesn’t work with standard USB hubs. As for the CPU load reduction, in theory this is helpful when using with a laptop to reduce fan spinning and power drain, although in practice I haven’t noticed much change (including when looking at CPU usage within the task manager, where it hovers at around 1-2%).
Of course, the most important question is whether it actually works better than the old eye tracker. Indeed, it has improved in a couple ways: higher precision and larger tracking area. After performing calibration, the precision is noticeably better (approximately 2-3X, with about 5 mm diameter noise), although it still exhibits consistent error (as much as 2 cm) towards the periphery. It has always been a mystery to me why this bias cannot be fixed by calibration, because it is so consistent. For this reason, I would still recommend sticking with a screen of up to 24 inches, even though the requirements technically now support up to 27 or 30 inches depending on aspect ratio.
The other improvement is in the tracking area. I use a motorized sit/stand desk, and I used to find that the change in the position of my head in standing position was enough to go out of range of the tracker. That is no longer a problem, indicating a major improvement.
Overall I’m happy with the new device, enough that I ordered one for both home and work. My biggest complaint at this point remains the error when looking towards the sides of my screen, which seems like it ought to be fixable in software. Tobii does update the software pretty regularly, so hopefully they will get to this at some point!