Ulefone Power Armor 13 Review

Sensors, infrared rangefinder

The Ulefone Power Armor 13 arrives with an expansive set of sensors which includes an accelerometer, magnetic field, orientation, gyroscope, light, pressure (barometer), proximity, gravity, linear acceleration, rotation vector, game rotation vector, step counter, geomagnetic rotation vector. There's a side-mounted fingerprint sensor that's fast and accurate with plenty of customizable features that can be assigned to it.

One of the main selling points of the Power Armor 13, besides its huge battery, is the infrared rangefinder. This module is fitted within the top of the smartphone. You have to open the Rangefinder app, point the device in the desired direction until you see the beam's red dot, and measure the distance to this selected point. There are also options for measuring area, volume, and Pythagoras. When measuring length, there can be an error of +/-1 cm for distance from 0 to 20 meters. For distances from 20 to 40 m, the error can be +/-2.5 cm.

How does it work? The smartphone continuously emits an infrared signal by an infrared light-emitting diode onto a target object. The object reflects the IR ray, which is detected by an IR-sensitive photocell placed next to the IR emitter. The photocell, the object, and the IR transmitter shape a triangular arrangement. The determination of the distance is done either based on triangulation or on the time needed for the IR ray to travel to the object and reflect back.