flickering screen

My Mac is a couple of months old and lately the screen keeps flickering on the left side of the screen. At first it happened on the odd occassion, now it's all the time and most annoying. It has nothing to do with the, energy saver (turned off the 'automatically adjust brightness as ambient light changes', nothing seems to work. I have read that in 2008/09 there was a similar issue and recently and some people just simply had to return their macs. I hope not, but I am curious to why this is happening. I have everything up to date, just want to know why this is happening and what to do about it. I hope someone can advise or help as I don't fancy sending this back now.

Model Name: iMac

Model Identifier: iMac12,2

Processor Name: Intel Core i5

Processor Speed: 3.1 GHz

Number of Processors: 1

Total Number of Cores: 4

L2 Cache (per Core): 256 KB

L3 Cache: 6 MB

Memory: 8 GB

Boot ROM Version: IM121.0047.B0A

SMC Version (system): 1.72f1