Many times, companies adopt an approach to quality that is overly narrow, functionally centered, and not fully integrated across the business. To some extent, this is a natural, but unintentional, by-product of the quality function as the company’s regulatory interface is Quality control mindset. It is also a prescription for trouble. Quality assurance can actually help the productivity and improve the bottom line.
Quality Assurance is essentially process oriented and focuses on defect prevention, while quality control is product oriented and focuses on defect identification.
Quality assurance activities are usually determined before production work begins and these activities are performed while the product is being developed and is more to do with the way we work and the priorities we define. In contrast, Quality control activities are performed after the product is developed or manufactured.
There are many many real time quality control equipments, the choice of the equipment depends upon the industry you work in. I have seen and worked on check weighers, metal detectors, vision inspection systems, Xray inspection systems, Seal integrity checking equipments, moisture and oil content analyzers and so on...