article_snippet: The demo version (pictured) was covered in glass that measures 0.9mm thick, and Qualcomm did not reveal what the maximum thickness is. 
article_snippet: A prototype version of the sensor is on display at Mobile World Congress in Barcelona.
article_snippet: When a finger is placed on the tiny sensor - the demo version has a 9mm by 4mm
article_snippet: A prototype version of the sensor was covered in glass that measures 0.9mm thick, and Qualcomm did not reveal what the maximum thickness is.
article_snippet: For its prototype, Fujitsu has built a miniature scanner so its fits on the front of a smartphone.