Sensor left of camera (not LED) - Micro Sd reader

What is the sensor positioned left of the camera on the venue 11 pro 7130? Not the Camera 'ON' indicator LED but the other one left of that. Is it a proximity sensor?

Also having a few issues with micro SD card reader. When the sd card is inserted and I unplug the power cable the system crashes. I've tried installing the latest card reader drivers, installing the latest Bios but nothing works. The new driver gets deleted and replaced with an older driver upon reboot. Only solution so far is to eject sd card.  Anyone have a better solution to this problem?