Imaging performance comparison between CMOS and sCMOS detectors in a vibration test on large areas using digital holographic interferometry

A comparison of the interferometric imaging performance of two different cameras during a vibration study is presented. One of the cameras has a high speed CMOS sensor and the second one uses a high resolution (scientific) sCMOS sensor. This comparison is based on the interferometric response as a merit parameter of these sensors which is not a conventional procedure. Even when the current standard for image quality is on the signal to noise ratio calculations; an interferometric test to evaluate the fringe pattern visibility is equivalent to the contrast to noise ratio value. An out of plane digital holographic interferometer is used to test each camera once at the time with the same experimental conditions. The object under study is a metallically framed table with a Formica cover with an observable area of 1.1 m(2). The sample is deformed by means of a controlled vibration induced by a tip ended linear step motor. Results from each camera are presented as the retrieved optical phase during the vibration. Finally, some conclusions based on the post processed images are presented suggesting a smoother optical phase obtained with the sCMOS camera.