If there's one major annoyance with the iPhone it's that it lacks the ability to display status indicators when the phone is in sleep mode. If you're out and about and just want to know how much battery power is left, you have to press the Home button, which lights up the whole display, and then check the status icon for the battery.

This not only requires the press of a button every time you want to know some little detail such as the battery status, signal strength or the time but also the glaring bright display can be jolting in the dark confines of someplace place like a cinema.

See also: Apple iPhone 3G review

Nokia has tried to work around this issue by displaying monochromatic status indicators on the display even with the backlight turned off in their earlier phones. However, since it didn't work in very dark or very bright lighting conditions, they've stopped using this method on more recent models.

Sony Ericsson deals with this by activating the backlight at a much lower brightness to display the status indicators when a button is pressed. This method works well for the most part, but it still does require that press of an extra button.

However, according to Apple Insider, Apple has filled a patent that details how status indication could be achieved on an iPhone without having to keep the display powered on the whole time or necessitating the press of a button.

Credited to an Apple engineer by the name of Michael Rosenblatt, the patent describes a method of placing two light sources behind the display, one stacked on top of the other. The light source immediately below the display would be the bright, primary one and would itself be placed over a low-powered source that emits very faint light.

Apparently, the secondary light source could then be made to pass light through several transparent or semi-transparent areas on the main lighting source, thus emerging as faintly lit, distinct status icons on the screen, even when the phone is in sleep mode. The secondary light source could then be used to create a blinking effect or something resembling the pulsing behaviour of the sleep indicator on Macs.

Since this method requires changes to the hardware, don't expect to see it enabled via a software update, if ever. Apple has a lengthy history of patenting ideas and technologies that never actually make it into the hands of consumers.

That Apple is looking into ways to add more status indicators to iPhone is certainly good news. One way they could add them on the software level even to current iPhones is to have some more icons in the status bar to reflect important information like unread email and SMS text messages or missed calls. That would eliminate the need to unlock the phone or scroll to a different Home screen to find these details and make the phone a tad more accessible.

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