get Region contents

Hi,

I have to detect a certain alphanumeric string on the screen. However, the built-in OCR feature is too buggy to provide usable results. Hence I have though of a workaround..

I have realized that since I first have to type the alphanumeric string I am trying to detect later, I can just capture whatever I have typed and then use this as a usual image pattern to find on the screen.
My problem here is capturing the region to use it later as a pattern. I have tried using the "capture" function which should return a path of the image where the region was saved, however when I search at a returned path, I can't find the image there.

Is that a bug?
Is there any other way to save region contents?

Thanks!
Eugene