Posted on 04/30/2015 2:57:59 PM PDT by 9thLife
On the back of the new Apple Watch, there are two sets of lights and sensors. One sends out and receives visible light, while the other works in the infrared part of the spectrum. Together, they form the technical core of the watch’s coolest feature—a heart rate monitor.
This kind of design—using optical sensors to measure pulse—is not unprecedented, but Apple, of course, claims to have improved the system over competitors like the Basis Peak, Samsung Gear Fit, or Mio’s line of activity monitors. Which would be a good thing, because these systems have struggled with their accuracy.
“Everyone has been joking about the inaccuracy of the prior technologies and that’s what we’ve got to get past to get people really comfortable with this,” UCSF’s Michael Blum told me last year at a Samsung event.
And because of the technology that most smart watch makers, including Apple, have chosen, the problems may be exacerbated if you have darker skin.
Why?
The technology is based on a laboratory technique called photoplethysmography, which uses a “pulse oximeter” to measure the components of the blood. A light pulse is sent through the skin and picked up by a sensor. Based on how the light scatters, the sensor can measure how oxygenated the blood is, which allows one to calculate heart-rate based on how often fresh, arterial blood is pumping through.
In the medical context, this oxygen level tends to be measured by a little finger cuff. So the light is on one side of the finger and the sensor is on the other. Even in this more controlled setting, there have been conflicting scientific reports about whether skin color impacts the accuracy of readings.
But no one wants to wear a finger cuff around while they work out, so fitness band companies have had to make do with the wrist. Even a flashlight can shine easily through one’s fingers, which makes the sensing task easier. A wrist-mounted sensor has to rely on the light that’s reflected back from the blood, not shining through it. That’s harder.
The skin on the back of the wrist tends to be darker, too, especially for people with more melanin. “The light has to penetrate through several layers…and so the higher the person is on the Fitzpatrick scale (a measure of skin tone), the more difficult it is for light to bounce back,” explained Basis COO Bharat Vasan to CNET.
Basis, and presumably Apple, try to compensate for skin tone by shining brighter light when someone’s complexion is darker.
Without knowing the precise nature of Apple’s lights and sensors, it’s hard to know whether the device will have hard limits on its ability to work with different skin tones. Apple probably had to choose a center point for calibrating the device, too, making the trade-off between lighting power and battery drain.
Like many technology companies, Apple’s executives form a key early testing team. The company’s top people become the company’s default customers. And if people with dark skin do have problems with the watch’s heart-rate sensor, none of Apple’s top executives would have experienced it.
applexecs
Using optical technology to measure heart rate might also mean that people with darker skin will experience a greater drain on their watch battery, because of the more intense light required to power the sensor. The light required to do accurate measurements was enough to push Apple-competitor Jawbone away from an optical system to an electrical one: “Because bioimpedance requires significantly less power compared to optical sensors for same level of accuracy, we can deliver a smaller form factor and longer battery life,” they claim.
We won’t know for sure until lots of these watches are strapped onto lots of different wrists, but consider the broader idea: wearables want to be intimate devices that interact deeply with our bodies. Are companies like Apple really ready to reckon with the diversity of bodies that exist in the world?
O, what a dilemma.
Fabulously racist!
electronics are racist.
photoplethysmography
This is great.if it don’t work on a bro’s wrist.howdat gonna play out...Huhh?
Fitzpatrick scale (a measure of skin tone) I like this term! We can now use sentences like, the teens were on the high end of the Fitzpatrick scale!
Depends on what color. Apple says tattoos can cause watch problems
http://www.bbc.com/news/technology-32537030
I’ll remember that, LOL!
apparently wrist tats block these sensors too
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The Apple Watch only will sync with an iPhone - both have to be correctly registered with Apple - account name and password...
If you steal an Apple Watch it won’t work - Fitzgerald scale be damned.
Not racist, just an honest observation...
Depends on the ink. . .
LOL ... these days you’re a racist it you hiccup the wrong way ... :-) ...
Since when is a heart rate monitor anything’s coolest feature?
Oh, GEE, maybe Apple did go outside the Apple Executive team to test the Apple Watch on people other then lily white caucasians. The article is FUD!
Apple Recruiting Pro Athletes to Test iWatch's Fitness Capabilities
Friday June 20, 2014 1:34 pm PDT by Juli CloverApple's iWatch is currently being tested by professional athletes from the MLB, NHL, and NBA to measure its fitness capabilities in rigorous training environments, reports 9to5Mac, citing a source with knowledge of the testing. Apple has reportedly invited several athletes, like LA Lakers player Kobe Bryant, to its Cupertino campus to discuss the iWatch.
Apple is said to be working with Los Angeles Lakers basketball player Kobe Bryant, Los Angeles Kings right winger Dustin Brown, and a few other star athletes, including a player from the Boston Red Sox, on the testing project. The athletes are said to have signed non-disclosure-agreements regarding the existence of the upcoming Apple wearable device.
Kobe Bryant was seen on the Apple campus back in May and is said to have met with Apple's chief designer Jony Ive, who has a leading role developing the iWatch. The athletes are likely testing out the multitude of health and fitness sensors built into the device, said to measure everything from sleep quality to heart rate to provide an overall picture of health.
The source also reiterates that Apple's iWatch will be "positioned as a fashion accessory," which is in line with previous reports from KGI Securities analyst Ming-Chi Kuo. Kuo has predicted that Apple will release the iWatch at multiple price points and in a variety of materials, competing with low and high-end watches alike. At the higher end, the iWatch could retail for thousands of dollars.
Both former Yves. St. Laurent CEO Paul Deneve, who serves as a vice president, and Angela Ahrendts, in charge of retail stores, are said to be involved in marketing and strategies for selling fashion products at Apple locations.
According to recent reports from reputable news outlets, the iWatch will come in at least two sizes, with one device having a screen size of 2.5 inches. The design is said to feature a slightly rectangular face that protrudes slightly from a band to create an arch shape around the wrist. The iWatch, which may launch at an October event, is also said to include a sapphire crystal display, a touch interface, integration with existing iOS devices, and wireless charging capabilities.
So much for their claims of not working with minorities and skin tones. So much for their ClickBait™ FUD article!
Why is people of color ok, but colored people isn’t? It seems like the symmetrical property of math covers this.
I don't think that's taught anymore.
Very good point, though.
“Apple’s iWatch will be “positioned as a fashion accessory,”
Says it was tested, not that it passed. Also calls it a fashion accessory. Getting the NBA to wear bling nobody else can get isn’t all that hard.
The main problem with it, is that it isn’t needed and doesn’t free you from a phone. It’ll be as big as apple glasses.
The fact is that cognoscenti just escaped clocks strapped to an appendage in the last few years. We aren’t going back,,,,
See some actual FACTS (instead of ridiculous speculations totally divorced from reality) to which this link will lead you:
The essence of the fact-based article is:
“The Apple Watch works fine with dark-colored skin, scars and skin abrasions, which are translucent, allowing light to pass through. Tattoo ink is opaque, preventing outside light from penetrating your skin.”
Once again bitten by the fact that some people just can't use the English vocabulary properly.
"DARK" and "OPAQUE" are not synonyms, any more than "LIGHT" and "TRANSLUCENT" are synonyms.
I wager that if somebody painted their wrist with opaque white paint, the watch wouldn't work well.
Ya just can't fix STUPID.
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