Tango Project: How the Lenovo Phab 2 Pro ToF Camera Works

Tango Project: How the Lenovo Phab 2 Pro ToF Camera Works

In June 2016, Lenovo introduced Lenovo Phab 2 Pro, the first device to offer Google augmented reality technology. Part of Project Tango, the device came with support for the Time-of-Flight (ToF) camera, capable of capturing the dimensions of the users environment. Learn how this technology works on the video below.

The Tango Project became known in early 2014, when Google launched Peanut Phone and Yellowstone Tablet, although both were built for developers only. Phab 2 Pro can now be purchased in some regions and already has a number of apps available on the Google Play Store.

The great asset of Tango devices is cameras. In addition to the normal RGB sensor, we have the ToF module. In this module we find an 850 nanometer infrared laser that emits pulses of light up to 100MHz. Thus, using the light reflected from the environment, it is possible to measure the distance of each and every pixel. The amplitude of the signal is also captured to the point where we have the exact measurement of each of the pixel distance. In multiple frames, these measurements are entered with the highest accuracy.

AndroidPIT lenovo phab 2 pro tof camera 4461
Lenovo Phab 2 Pro Time-of-Flight Camera Module / AndroidPIT

The Real3 sensor, developed by Infineon and PMD in Germany, is available in three versions. The Phab 2 Pro has a 224×172 pixel IRS1645C sensor. This may seem small, but enough to create a 3D image of a room. The smartphone not only captures one image but is able to evaluate each video frame and combine the artificial 3D images on the 3D model of the environment.

With a laser pulse rate of 100MHz, and an interval of 10 nanoseconds, if we multiply by the speed of light and divide by two, this equates to a maximum scanning distance of about 1.5 meters. In order to increase the range, the pulse rate may be varied between each frame individually.

This allows the camera to photograph frames with a shorter range and greater scanning accuracy in order to capture hand gestures, for example. This feature also merges lower frequency frames in order to measure a slightly larger room. And this whole process works regardless of the ambient light.

Finally, the fisheye lens camera measures extremely fast position changes that the smartphone makes in a room by analyzing digital images. In addition, Android Nougat natively supports Time-of-Flight cameras.

Now, check it all out in video:

And, did you enjoy what an augmented reality smartphone can do?

. (tagsToTranslate) What is Time-of-Flight (t) Camera Lenovo Phab 2 Pro (t) Google Tango Project (t) Tango Project