Apple has been cleared of misleading potential iPhone customers by exaggerating the quality of its display.
The UK's advertising watchdog rejected a complaint that a London Underground poster showed better quality pictures than the iPhone could reproduce.
Adverts for Apple's iPhone on the London Underground were designed to show off the machine's ability to be used to surf the internet, and displayed a sample internet page of Times Online, the website of The Times newspaper.
A member of the public complained to advertising watchdog the Advertising Standards Authority (ASA) because he did not believe that the iPhone could reproduce web pages at as high a quality as was depicted in the ad.
The ASA rejected the complaint, but only after discovering that Apple had matched the quality of the picture in the ad almost exactly with the quality of image produced by the iPhone.
"Apple said the Times Online screen images in the posters originated as screen grabs from the iPhone itself," said the ASA ruling. "They said the quality of the poster image was dependent on the means of reproduction rather than the quality of the input image. They argued that, if the image had simply been enlarged, it would have been unrecognisable and unusable, and therefore had to be manipulated in post-production to vectorise text and graphic elements of the image to make it scalable for large print use."
"[Apple] believed it was the resolution of the picture that was important and in this case the poster screen grab image resolution was 162.8 ppi [pixels per inch], which was fractionally lower than the resolution of the iPhone screen itself, which was 163ppi," it said.
The ASA accepted that the reproduction of the picutre involved "a few minor manipulations", but that these did not alter the fact that the resolution of the web page on the poster and on the iPhone screen were almost exactly the same.
"Apple gave the ASA a demonstration of the iPhone and also showed how the screen grab was converted to a poster image," the ASA said. "We considered that the quality of web page images on the iPhone were comparable to that featured in the posters and concluded that the posters were unlikely to mislead about the image quality achievable with the iPhone."
The ASA cleared the advert of breaching its rules on substantiation and truthfulness.