Kindle DX 2 screen contrast improvement analysis

The improved Kindle DX 2 screen contrast is its big selling point. Amazon hasn’t really revealed too much about what led to this improved screen contrast.

Well, let’s take a closer look and see what factors might have helped improve the Kindle DX 2’s screen contrast.

Kindle DX 2 Screen Contrast Improvement – possible Factors

Here are the 3 factors that we can identify right away –

  1. Actual hardware improvements. eInk say the Pearl screen has 10:1 contrast as compared to the 7:1 contrast in previous versions. Quite frankly it doesn’t really seem like the hardware improvement by itself is 43%. In terms of measurements we have this from Bruce Wilson’s comment at Teleread

    From density numbers alone – white is a little whiter, black is a lot blacker.

    Old White Kindle DX 1 (6 months old):
    white area density = 0.46, Lab = (65.8, -2.3, 0.6)
    black area density = 1.30, Lab = (26.6, -1.0, -2.2)

    New Graphite Kindle DX 2:
    white area density = 0.42, Lab = (68.2, -2.4, 0.9)
    black area density = 1.58, Lab = (18.5, -0.1, -3.6)

    I used a Datacolor Spectrocolorimeter model 1005. “Lab” is a color space measurement like RGB, only for print.

  2. Graphite Casing. Amazon have implied this is not factored into the 50% better contrast – However, it’s clear after playing around with the Kindle DX 2 that the graphite casing has quite an important role in making the screen look better.  
  3. Speckling on the Screen. There are very tiny speckles on the screen of the Kindle DX 2 when you zoom in. Click on the last photo on the Kindle DX 2 Photo page to see this speckling. When photos have noise like this added to them it improves their contrast – It’s hard to believe there could be any other reason speckling would be added to the screen of the Kindle DX 2.

We also have two additional possibilities –  

  1. Software improvements. Kindle software upgrades have improved Kindle screen contrast in the past by making the text bolder and it’s possible that Kindle DX 2 comes with some software improvements. Kindle DX 2 comes with firmware version 2.5.5 and it makes you wonder if that firmware version includes screen contrast tweaks.
  2. Additional changes in the screen hardware. There’s a very interesting mention in the official Kindle forum that the Kindle DX 2 screen is noticeably whiter if you tilt it a little rather than look at it straight on. For my Kindle DX 2 this is true – It’s noticeably whiter when tilted a little. Is this by design? Is this a byproduct of the new screen technology?  

The former is very, very likely while we understand too little about the latter to factor it in.

Breaking down the supposed 50% screen contrast improvement

After shooting a lot of Kindle DX 2 videos and taking a lot of photos and comparing screens in all sorts of lighting conditions it seems to me –

  1. Compared to Kindle 2 Global – Kindle DX 2 screen is 25% to 30% better normally, 30% better in sunlight, and 30% better when Kindle DX 2 and Kindle 2 are both tilted a bit. 
  2. Compared to Kindle DX 1 – Kindle DX 2 screen is 40% better normally, 45% better in sunlight or when both are tilted a bit.

There isn’t really a 50% improvement in screen contrast. It’s 40% to 45% when compared with Kindle DX 2 and 25% to 30% when compared with Kindle 2 Global. 

Furthermore it seems that this 40% improvement is broken down into –

  1. Half due to hardware improvements. If the spectrocolorimeter readings are correct hardware improvements might be responsible for as much as three-quarters of the improvement.
  2. A quarter due to the graphite casing. 
  3. A quarter due to the speckling.

The Kindle 2 Global screen is much closer to the Kindle DX 2 ‘better hardware screen’ than the Kindle DX 1 screen. This might be due to software tweaks or International Kindle 2s getting better screens or perhaps my Kindle 2 global was an exceptionally good version.

How did 50% screen contrast improvement and a graphite case and speckling and possible software improvements add up to 40%?

Well, it seems that eInk messed up and Amazon did as much as they could to make up for it.

Seriously – Look at the videos and photos. If you happen to have any of the earlier Kindles and the Kindle DX 2 compare them in various lighting conditions. If eInk’s claim is valid and there’s a 50% screen contrast improvement then it means that the graphite casing and the speckling and the software improvements (if any) contributed minus 10%.

The far more likely case is that eInk did a terrible job with their screens and improved just 20%. Then Amazon did a lot of brainstorming and came up with the graphite case and the speckling design for the screen and software improvements to get to 40%.

Amazon better hope Pixel Qi or Qualcomm Mirasol deliver color eInk screens soon because Amazon can’t keep compensating for eInk’s inadequacies with software upgrades and smart design decisions. The new Kindle DX 2 has managed to use almost every design and software trick possible to improve screen contrast (we’re including font sharpness improvements in the Kindle 2.5 upgrade). It’s had to because the actual screen technology from eInk isn’t improving fast enough.

Quick Summary 

Yes, Kindle DX 2 has a noticeably better screen. No, eInk isn’t responsible for all of the improvement. If eInk really would have improved their eInk screens 50% we would be looking at 70% to 75% better screen contrast on the Kindle DX 2.

PVI supplies Kindle, iPad screen technology

If you thought it was impressive that PVI/eInk supply screens for the Kindle, Sony Reader, Nook, and pretty much every dedicated eReader device, wait till you hear this (via Electronista and Wall Street Journal) –

Hydis Technology Co., Prime View’s South Korean subsidiary, … provides a key display technology used in Apple Inc.’s iPad …

… the technology, known as advanced fringe field switching, that widens the screen’s viewing angles and improves visibility

Apple refers to the technology as IPS – in-place switching.

PVI’s IPS technology and LG Display ties

Here’s a little more on PVI’s in-plane switching technology from DigiTimes

The Hydis-developed FFS technology has been further developed into AFFS (advanced fringe field switching) and AFFS+. The benefits of AFFS technologies include readability under sunlight, low power consumption, wide viewing angle, fast response time and high brightness, PVI said.

Note that the iPad does not have the readability under sunlight promised in AFFS (perhaps it has FFS, AFFS’ predecessor) – However, it does indicate that a future version may well be readable in sunlight.

WSJ fills in some details on how PVI technology got into the iPad –

Prime View in December signed a cross-licensing pact with LG Display Co., which analysts have said is likely one of the iPad’s flat-panel suppliers.

LG Display said that it would invest $30.5 million in Hydis through a bond purchase, following a $10 million investment in Prime View

Electronista point out that there is a $500 million Apple-LG Display deal –

Apple hasn’t confirmed the deals and doesn’t normally divulge which companies supply its individual components. It did recently strike a $500 million deal with LG Display to produce screens across its lineup.

It’s interesting to see PVI gradually grow and expand. The deal with LG Display in December 2009 was their second major deal of the year. PVI had bought eInk Corporation of Cambridge Massachusetts in June 2009 for $215 million.

PVI shows off new eReader Screen technology

T3 has two videos of new eInk screens from PVI that are promised to reach eReader makers by end 2010 and customers by end 2010 or early 2011. Great to know that technology that should have arrived a year ago is still a year away.

Here’s what’s promised –

improvement from the standard 7:1 contrast ratio screens – to the much easier on the eye 12:1 ratio – and a faster refresh rate. E Ink claims this refresh rate is fast enough to support simple animations.

Another prototype shown boasts a larger flexible display with claims from E Ink that it’s tough enough to take a fair size impact without it blinking a single pixel.

On the plus side the eInk display in the first video has excellent contrast.

Companies that profit from both Kindle and iPad

There are lots of companies that are profiting from both Kindle and iPad –

  1. PVI is perhaps one of the most critical since they supply the key screen technology for both Kindle and iPad.  
  2. FoxConn – It manufactures the Kindle and Apple devices like iPhone – making it likely it’s also manufacturing the iPad. 
  3. Amazon – Yes, that’s right. Kindle for iPad’s 480,000 books and worldwide availability is much more impressive than the iBooks’ 60,000 books and US only availability.
  4. Newspaper and magazine publishers.
  5. Book Publishers.

It’s an interesting thought – while the Press keep playing up the Kindle vs iPad angle, multiple companies, including Amazon, just see them as two separate channels/devices that can both be a source of profit.

Flexible eInk screens – the possibilities

For all the talk of flexible eInk screens there’s not really been much discussion of what their actual impact would be. Let’s explore if there’s more to flexible eInk than we realize.

What are the Obvious Benefits of flexible eInk screens? 

The first few benefits that spring to mind are pretty significant –

  1. Unbreakable or difficult to break screens.  
  2. The option to make eReaders foldable and/or rollable and thus more convenient and portable.
  3. A similar, but not identical, benefit is the possibility to give small form factor devices screens that are double or triple in size.
  4. The ability to expand use of eInk screens to a variety of non-flat products i.e. watches, clothing, etc.

Take a look at this video (00:25 onwards; sort of not safe for work; some people could be offended by intro/outro/a few of the designs) for what eInk based, infinitely redesignable T-Shirts could be like.

What are some of the other possible benefits of flexible eInk screens?

With a little thought we get into some really interesting uses –  

  1. Using rolling screens or double screens to eliminate eInk reload delays.

    You could refresh the part that is not currently shown while the reader is reading the part that is shown.

    This could be in the form of a back screen that refreshes while the front screen is being read and then replaces the front screen.
    Or it could literally be a rolling display that scrolls around and refreshes lines of eInk before they are visible.

  2. Switching between concave and convex modes to better adjust to conditions i.e.

    When you want more privacy or want less reflections and less outside light you switch to concave mode.

    When you want to be able to catch more light or read while lying in bed and at obtuse angles, you switch to convex mode. Convex mode would also be useful when adding freehand notes.

  3. Rigid Screen Versus Flexible Screen mode of the eReader where users can choose what works better for them. 

How could use of flexible eInk screens in other areas help eReaders?

Making eInk screens flexible adds the possibilityof using them in lots of other areas i.e.

  1. In defence (the Arizona State project with the US Army is focused on flexible wearable displays for soldiers).
  2. On clothing and in watches. 
  3. In retail displays. 
  4. For cellphones.

This leads to innovations that can be brought back to eReaders. For example, solar powered eInk (which Neolux is already working on).

Even more importantly it leads to advances in eInk technology and price drops that are crucial for eReaders to become more popular.