IHS Markit: [Display Dynamics] Display-based fingerprint solutions Q & AQuestion: Will Apple return with Touch ID under the glass?
Answer: No, Apple will not return to Touch ID under the glass. Apple already applied for many DFP patents. The silicon Touch ID conflicts with 18:9 displays (or wider aspect ratios like 19.5:9) because there is no space for the silicon fingerprint sensor on the screen. We believe Apple will continue to use Face ID, which is on the current iPhone X, for two to three years until it develops its own DFP solution, possibly ultrasonic. Apple’s evolutionary steps will be as follows:
Answer: No, Apple will not return to Touch ID under the glass. Apple already applied for many DFP patents. The silicon Touch ID conflicts with 18:9 displays (or wider aspect ratios like 19.5:9) because there is no space for the silicon fingerprint sensor on the screen. We believe Apple will continue to use Face ID, which is on the current iPhone X, for two to three years until it develops its own DFP solution, possibly ultrasonic. Apple’s evolutionary steps will be as follows:
- Use structured light for Face ID to solve its biometric ID needs. Meanwhile, build a mature supply chain for the next steps—vertical-cavity surface-emitting laser (VCSEL) light source and diffractive optics element (DOE) by wafer-level optics.
- Use the artificial reality (AR) kit only to support the 2D camera, with no 3D depth sensing. Make AR well-known to end users.
- Develop a new display fingerprint (DFP) technology to replace Face ID for biometric ID on the front side of the smartphone.
- Enhance its structured light solution—or develop time-of-flight (ToF) or active stereo vision—to deliver a 3D sensing upgrade to the AR kit.
- Develop an optical wafer-level package to solve the camera issue on the rear side of the phone.
What David is saying is, current fingerprint solutions are all under-display technologies. Apple won't try to cram the Touch ID silicon under the glass. Apple will however, wait for TFT-based sensors (true in-display) solutions before implementing. These are known as Display Fingerprint solutions (DFP) and are less bulky and offer better performance.
When I read this last year, I was hesitant about about Apple ditching Face ID. Now, with Kuo and Credit Suisse opinions converging, it seems very likely we'll see and end to Face ID. It appears Apple's strategic plan is to use VCSEL and DOE technology and supply chain developed for Face ID and put it to use at the back of the iPhone. Putting this technology on the front of the phone is overkill for biometrics and Animojis and doesn't allow for bezel-less displays. You want 3D mapping on the rear camera to see the world in AR terms.
If you're wondering who David Hsieh is, he is basically the Ming-Chi Kuo of the display world with about 30 years of experience in the industry. He used to be VP of DisplaySearch for those who have been following the industry for the past few decades.