Kunal, before you can hope to measure quality you have to come up with a definition for the term quality that is applicable in your context. We've had some lively discussion on this in the past. If you consider quality as relating to adherence to process, then this is measurable. If you consider quality as value to an audience, this is more difficult to measure. You might also want to google quality metrics.
Quality is all about a measure of
1.number of defects found
2. the tests run
3.the system covered by the tests.
if you are in a mood to improve quality of a software,going through the application and finding,reporting bug is a good practice that's what most testers do.