Take thumb impression as input in iPad

Here in my iPad application i need to upload one application form along with a image and a signature or thumb impression, so how to take the开发者_高级运维 thumb impression from a person in iPad. Here i am successfully did all the stuffs except taking thumb impression as input please anybody let me know how to take thumb impression. Thanks in advance.

Regards

GuruPrasad R Gujjar.

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Forget about it. Taking the THUMB IMPRESSION with an iPad is just impossible without a custom made external accessory to do just that.

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Haha, funny!

You can tell the user to press his finger on a glass prism http://en.wikipedia.org/wiki/Prism_(optics) and then you will be able to capture an image with very high contrast.

Actually now that I think about it you could actually fix the prism to a special desk and it can be useful for certain settings (authentication in a conference).

Note that I demand 1 BTC (bitcoin) royalties for every device that is sold with this technology!