Pixel Envy

Written by Nick Heer.

On Bloomberg’s Report That Apple Downgraded the Accuracy of Face ID to Improve iPhone X Production Speed

Alex Webb and Sam Kim, Bloomberg:

As of early fall, it was clearer than ever that production problems meant Apple Inc. wouldn’t have enough iPhone Xs in time for the holidays. The challenge was how to make the sophisticated phone — with advanced features such as facial recognition — in large enough numbers.

As Wall Street analysts and fan blogs watched for signs that the company would stumble, Apple came up with a solution: It quietly told suppliers they could reduce the accuracy of the face-recognition technology to make it easier to manufacture, according to people familiar with the situation.

The implication at this point in the story is that the facial recognition technology that will be shipping to consumers may not necessarily be as thorough as Apple has been promoting it in its iPhone X marketing materials:

Face ID revolutionizes authentication on iPhone X, using a state-of-the-art TrueDepth camera system made up of a dot projector, infrared camera and flood illuminator, and is powered by A11 Bionic to accurately map and recognize a face. These advanced depth-sensing technologies work together to securely unlock iPhone, enable Apple Pay, gain access to secure apps and many more new features.

Face ID projects more than 30,000 invisible IR dots. The IR image and dot pattern are pushed through neural networks to create a mathematical model of your face and send the data to the secure enclave to confirm a match, while adapting to physical changes in appearance over time. All saved facial information is protected by the secure enclave to keep data extremely secure, while all of the processing is done on-device and not in the cloud to protect user privacy. Face ID only unlocks iPhone X when customers look at it and is designed to prevent spoofing by photos or masks.

All biometric technologies are subject to an elevated level of scrutiny. Even before Touch ID was announced, early skeptics predicted that it could be easily fooled like other fingerprint readers. Now, it’s Apple’s take on facial recognition that’s encouraging the same kinds of pre-launch dismissals and high levels of skepticism. That’s probably why Apple describes it in such detail in that press release excerpt above, and it’s likely also why they felt it necessary to issue a statement on Bloomberg’s report — something they rarely do for rumours:

“Customer excitement for iPhone X and Face ID has been incredible, and we can’t wait for customers to get their hands on it starting Friday, November 3. Face ID is a powerful and secure authentication system that’s incredibly easy and intuitive to use,” an Apple representative told Business Insider. “The quality and accuracy of Face ID haven’t changed. It continues to be 1 in a million probability of a random person unlocking your iPhone with Face ID.”

“Bloomberg’s claim that Apple has reduced the accuracy spec for Face ID is completely false and we expect Face ID to be the new gold standard for facial authentication,” the representative continued.

Apple’s statement here is not phrased in a deceptive or weaselly way. It is clear: Face ID won’t be worse in consumer devices than they have previously promised. This is a very clearly-worded dismissal of Bloomberg’s claim that facial recognition will be less accurate.

So what, if anything, is true in Bloomberg’s report?

Well, I can think of a few things, if we read between the lines a little later in the report:

The dot projector is at the heart of Apple’s production problems. In September, the Wall Street Journal reported that Apple was having trouble producing the modules that combine to make the dot projector, causing shortages. The dot projector uses something called a vertical cavity surface-emitting laser, or VCSEL. The laser beams light through a lens known as a wafer-level optic, which focuses it into the 30,000 points of infra-red light projected onto the user’s face. The laser is made of gallium arsenide, a semiconductor material, and the lens is constructed of glass; both are fragile and easily broken. Precision is key. If the microscopic components are off by even several microns, a fraction of a hair’s breadth, the technology might not work properly, according to people with knowledge of the situation.

[…]

To boost the number of usable dot projectors and accelerate production, Apple relaxed some of the specifications for Face ID, according to a different person with knowledge of the process. As a result, it took less time to test completed modules, one of the major sticking points, the person said.

I only know what has been published by Bloomberg and the Wall Street Journal, and what is in Apple’s press statement. Even with that limited information, though, I think it’s possible to guess at different ways that Bloomberg’s report may be a reflection of the complexity of producing the iPhone X at scale and how Apple’s statement reflects the shipping product:

  1. Apple may have over-engineered a component, or found a simpler way to make it without compromising accuracy or reliability.

  2. The testing may have been overly and unnecessarily cautious, and it was able to be relaxed slightly without compromising accuracy or reliability.

  3. Early components were required to meet more stringent requirements because the software needed a higher level of precision. Adjustments could have been made to the Face ID software to make it more reliable and exactly as accurate with components that aren’t quite as perfect as the earliest batch of components.

There is overlap between all of these possibilities — and I’m sure there are more — but I think my first guess is a reasonable interpretation of Bloomberg’s report and Apple’s statement. It also takes into account production ramp factors and last-minute adjustments that, while not ideal, are not entirely uncommon. These changes are usually made under the hood, but occasionally the results of these adjustments may be visible. For example, some early-batch first-generation iPhones had a bell icon on the ring/silent switch, for example. The point of a production ramp is that potential issues are found and, to the best they can be, eliminated so later production runs more smoothly. And it appears that this is the case, according to Bloomberg’s report:

For months, Apple investors have fretted that a shortage of iPhone Xs would send consumers into the arms of rival smartphone makers such as Samsung and Huawei Technologies Co. Apple seems to have overcome the biggest production hurdles. Sharp is working to bring the production yield for dot projectors above 50 percent, while LG Innotek has already surpassed that level, which both companies consider acceptable. Meanwhile, Apple is working with Taiwan’s Himax Technologies Inc. to boost production of lenses to make up for lower-than-needed output from Heptagon, a Singaporean company that so far has been the only lens supplier.

The iPhone X is clearly a very advanced device to produce, especially at the scale customers would like to see. But, while the facial recognition sensors seem to be a primary obstacle to that scale, Apple’s statement refutes the notion that Face ID will be compromised in any way. That doesn’t mean they haven’t taken steps to make production easier; it simply means that the production ramp is doing its job, albeit perhaps within a tighter timeframe.

I am not worried about the accuracy of Face ID today any more than I was yesterday, or any time previously. And, though I understand general skepticism of the technology, I don’t think you should worry about it any more than you might have before. The biggest worry I have is whether I’m going to get my order in fast enough to be able to get an iPhone X delivered to my door next Friday.