Xiaomi seems to be really obstinate in creating a mobile phone with a screen without any notch or hole for the front camera. We recently saw a patent of it where a pop-up camera was shown and now we have another one of these documents showing another idea, but this time a little more creative and bold.
The patent filed under the number CN 305868884 S on June 28, 2019 at the China Patent Office was published today. The description cites a completely notch-free screen and any other type of sensor and even shows a small rectangular rear module where the main cameras are housed. There are two sensors and a hidden third, see:
That way, the front camera just needs to slide like a side pop-up to appear. The patent does not mention whether this mechanism could rotate to the point of using dual sensors for selfies as well, but because there is a dedicated sensor for this we can assume not. The mechanism somewhat resembles the one used in Zenfone 6, which was a little more versatile at that point, but could generate more problems because it needs more movements to work.