You can think of the light interference patterns as a covering which interferes with the subtle energy-field, making it visible. That's what PIP is looking at. I'm using the light like the glove. The PIP scans show many colours and patterns on and around the body. It's all about pattern and colour recognition.
Different colours represent different frequencies of energy.
When you are looking at chakra colours on our visual equipment, you are not just seeing one colour, you are seeing a mixture of colours. If a chakra is behaving itself perfectly, one colour will predominate. For instance the throat chakra has more of a blue hue when it is healthy than when it is not. The same with the base chakra, it will be a dirty muddy brown if there are problems, and red if it is healthy. Also, when red kundalini energy goes elsewhere, that is, it goes to the wrong place at the wrong time, there is a potential danger.