UPDATE: This article previously speculated that the Apple Watch may have employed color filters. However closer inspection shows that it's a true RGB OLED structure and that the observed color leakage is actually the result of a color management scheme that enables the watch to more closely match the appearance of Apple's iPhone 6. Our watch also shows a red point that is well short of sRGB. Since others have measured watches with a closer match to sRGB red this discrepancy may be due to a color management error.
It's launch Friday for the Apple Watch and, from the looks of my Instagram feed, lots of people around the world are excitedly trying on Apple's latest creation. Everyone seems to want to know- does this mark the beginning of a game-changing new product category or is it merely a passing fad?
While it's probably a bit too early to pass judgement on the success or failure of the Apple Watch in those terms, we can take an objective look at the performance of the hardware now that it's arrived. I'm mostly interested in the display's color performance of course. So, after pairing it with my phone, my first move was to load it with a set of test images and point our spectroradiometer at the screen. Overall, it's a beautiful looking display and our measurements revealed a few interesting things about how Apple designed the watch to overcome battery limitations. Here's a summary of what we found:
The Apple Watch Sport we tested had a surprisingly narrow color gamut for an AMOLED display- a technology known for saturated color- covering just under 82% of the color gamut of the iPhone 6 it was paired to. The biggest miss in terms of color gamut coverage was in red where Apple chose to go with a less deep red that's a bit closer to orange by mixing in some of the other primaries.
Apple is clearly prioritizing light output, high power efficiency and matching the iPhone's gamut here over maximum color gamut coverage here. This makes a lot of sense in the context of the Apple Watch's limited battery size since our eyes are less sensitive to very deep reds (we see yellowish-greens best). Choosing a red that's closer to orange means our eyes will perceive reds as being brighter without the watch needing to spend extra energy to overcome our eye's insensitivity to the color.
Looking at the spectrum for green above, do you notice the two bumps on either side of the green peak in the center? Notice the two bumps on either side of the green peak in the center? These are likely the result of software color management on the watch. Bleeding in blue and red reduces the inherently deeply saturated green of the watch's OLED display, enabling it to more closely match the appearance of the iPhone's LCD display.
And that's all the data we've had time to collect since the watch only just arrived this afternoon! (for more detailed, deep dive on the watch's display, check out Ray Soniera's Apple Watch Shootout)
Overall, the Apple Watch display is excellent given the limitations Apple faced in terms of battery life and it will be really interesting to track how future iterations of this display improve. They will most likely have to look for a big breakthrough in display efficiency given the recent track record of battery technology if the Apple Watch display is going to catch up to the iPhone or even the latest HDR TVs that are starting to hit the market.