Damage diagnostic imaging approach based on ultrasonic guided waves (UGW) is a research hotspot in the fields of non-destructive testing and structural health monitoring

which can directly reflect the damage location and severity on aerospace structures. This paper summarizes the general process of UGW diagnostic imaging technology

introduces the research status of eight representative imaging algorithms

including phased array imaging

space-wave number filter imaging

inverse-time migration imaging

time reversal imaging

delay-and-sum imaging

model-based imaging

tomographic imaging and probabilistic-based imaging

and compares the application scope

advantages and disadvantages of these imaging algorithms. Then

the challenge and development trend of UGW diagnostic imaging technology are discussed according to the actual industrial application.