The thing everyone notices about Apple's new 4in iPhone 5 screen is that it's longer than the one of the iPhone 4S, but there is more to it than that. 

DisplayMate Technologies has compared the new screen with the one on Samsung's Galaxy S3 and has concluded that Apple's screen is better, or in DisplayMate's words: “More refined”. 

The iPhone 5 scored an A rating, beating the Galaxy S3 which only managed a B+ due to poor calibration and viewing angle issues.

DisplayMate looked at screen reflections, brightness and contrast, colours and intensities, viewing angles, display power consumption and effect on battery life, according to Apple Insider's report

"In every category that we measure (except Brightness Decrease with Viewing Angle), the performance of the iPhone 5 display has improved over the iPhone 4, sometimes by a bit and sometimes by a lot," said DisplayMate's Dr. Raymond Soneira. 

Improvements include

Decreased screen reflectance by 52 percent - “One of the lowest screen Reflectance values we have ever measured,” according to Soneira

Boosted contrast by 57 percent 

Improved colour accuracy

Very good display calibration 

“It is the Brightest Smartphone we have tested in the Shoot-Out series”

“Highest Contrast Rating for High Ambient Light for any Mobile device we have ever tested,” said Soneria.

And the: “Color Gamut and Factory Calibration are second only to the new iPad.”

The only negatives: 

The White Point is still somewhat too blue like most Smartphones

Maximum Brightness it has a shorter Running Time than the iPhone 4

Minor gamma intensity

"It is still probably more accurate than any display you own, unless you have a new iPad," added Soneira. 

iPhone 5 screen smashing news 

But the good news regarding the screen doesn't stop there. A smashed iPhone may be a thing of the past. Not only has Apple switched from a glass back to an aluminium back, it has emerged that replacing a broken screen will be easier. So easy, in fact, that Apple Geniuses will be able to do so in store. 

Apple retail sources are said to have told blog site iMore that equipment that can be used to replace iPhone screens has been turning up in Apple Stores. 

With the iPhone 4 and 4S it was necessary to send the phone off for refurbishment and Apple often gave customers a replacement model. The iPhone 5 is  more like the iPhone 3G and 3GS, with the LCD panel, touch sensor and glass housed together. This means the whole front can be easily replaced, which is easier than just the screen. In the case of the iPhone 4 and 4S some of the internal components lay on top of the screen, according to iMore.  

It's not just the screen that is easily replaced. According to iFixIt: “The iPhone 5 is easy to open and easy to repair.” iFixIt shows how easily the screen is removed with a suction cup. 

Not enough iPhones 

The only problem with this wonder screen is it is said to be part of the reason why supplies of the iPhone 5 are constrained. 

Sharp is said to be providing the screen, but according to Bloomberg, the company is “struggling to reduce defects in screens that include the new technology”. 

As we reported yesterday, discussing why Apple missed analyst targets for the first weekend of sales of the iPhone, Barclays analyst Ben Reitzes said: “Apple is facing significant production constraints due to a move toward in-cell display technology. Apple is struggling to keep up with demand.”

Apple admitted that supply of the iPhone 5 had not met demand when it announced that it had sold five million iPhones in the first weekend. 

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