Among the possible new technologies to be incorporated in this year’s refresh of the iPhone series, 3D sensing has generated a lot of interests in terms of applications. A 3D sensing solution requires an RGB camera module an infrared (IR) sensor module that uses VCSEL (vertical-cavity surface-emitting laser) as a light source. With more high-end smartphones adopt 3D sensing, TrendForce estimates that the worldwide market scale of IR sensor modules for mobile devices will reach US$145 million in 2017.

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Since Apple gained IPs related to 3D sensing via its acquisition of PrimeSense in 2013, there have been anticipations that future smartphones will one day feature facial recognition based on this technology. Jason Tsai, TrendForce’s wearable analyst, pointed out that the 3D facial recognition feature on smartphones is not going to match digitally created 3D models of human faces and match them with reference models in databases as most people would expect.

“Acquiring and processing data of 3D models is quite burdensome for smartphone hardware, especially if models are to be constructed in precise detail,” said Tsai. “To have a 3D facial recognition feature with an acceptable response time, smartphone makers are probably going to enhance the existing 2D facial recognition solutions with 3D sensing. Therefore, 3D sensing will be a supporting technology that mainly helps to determine whether the face that is being recorded comes from a real living person.”

Generally, solutions based on 3D sensing obtain dimensional data including depth values by scanning the environment within a defined range. These data in turn create digital 3D models that can be analyzed or matched with reference models in the database. Tsai noted that extending the scanning range and getting finer depth details of objects will take more computing power and time. 

“Scanning range and modeling capability have positive relationships with hardware specifications,” said Tsai. “In the realm of AR for mobile devices, applications are still too few to warrant the hardware cost for 3D sensing. There is also the issue of increasing power consumption. Consequently, smartphone makers are not too keen on using 3D sensing for AR-based features because this kind of innovations do not significantly increase the value of their products.”

On the other hand, 3D sensing can strengthen user security by making the facial recognition function of the device more accurate. This does not mean that smartphone has to create, store and match exact models of human faces. 3D sensing is just there to ensure that the smartphone can recognize that the facial image that the camera has captured comes from a real living person. 

“3D facial recognition for smartphones must be fast enough so that it can assist in tasks such as unlocking the device, mobile payment and identity verification,” Tsai pointed out. “Convenience and response time are just as important as accuracy in the adoption of new biometric technologies. Otherwise, consumers would still prefer passwords and fingerprints.”

Tsai added that as 3D sensing components will push up hardware cost for smartphone makers, such solutions will initially be available for the high-end market segment. Gradually, there will be more smartphones featuring this kind of technology in the near future.