It has emerged that Apple has already sent out invitations to the San Francisco launch of its new iPad 3 this week.

As expected, iPad3 will be unveiled on March 7 at a special even in the Yerba Buena Center for the Arts in San Francisco.

Apple’s invitation says: “We have something you really have to see. And touch.”

The invitation shows a finger over an iPad screen, pointing to the Calendar app, which is set to March 7.

iPad3 is expected to offer a much higher resolution Full HD screen.

Bloomberg reports that iPad 3 processor will be a “quad-core” device, a step that would put Apple’s tablet ahead of competing devices such as Samsung’s Galaxy Tab 10.1 in terms of computing power, and enable a new generation of high-powered apps.

Tech site MacRumors claims that iPad3 will also be more expensive.

“The iPad 3 costs $80 more for the equivalent Wi-Fi models, and $70 more for the equivalent 3G models,” said MacRumors, reporting on leaks from Chinese factories.

MacRumors claims that the device will be “near identical” to iPad 2, which tallies with other leaks from Apple accessory makers.

iPad3 will reportedly look similar to iPad, but with a higher-res screen, faster processor and Siri voice control

The device is expected to look similar to the current iPad 2, but offer a far sharper HD screen and a next-generation processor capable of impressive visual effects.

The tech blog iMore reported that iPad3 is also rumored to feature the anticipated 2048×1536 Retina display, and the quad-core Apple A6 chip to boost its speed and effectiveness.

Ezra Gottheil, an analyst with Technology Business Research said last week that a March debut of the gadget was a “sure bet”.

Speaking to Computer World, Ezra Gotteil said: “It will have a higher-resolution screen.”

“That’s important to them because it means the iPad will work well with home cinema systems, since it will display full HD.”

Leaked images also hint at a casing that iPad3 looks similar to iPad 2. The validity of those pictures, could not be determined.

All Things D, a blog owned by Dow Jones, reported that the device will be introduced during a special Apple event in San Francisco.

The late Steve Jobs introduced the previous iPad there at about the same time last year.

Various Apple accessory companies were showing off iPad 3 cases behind closed doors at this year’s Consumer Electronics Show in Las Vegas, all of which hinted at a gadget broadly similar in shape to last year’s.

Popular Apple-watching website iLounge claimed to have seen a prototype behind the scenes at the show.

The site’s editor-in-chief, Jeremy Horwitz said: “From the front, the next iPad and iPad 2 appear to look basically the same – apart, of course, from the screen. That’s going to be Apple’s big focus when the new device is announced.”