Automatic phase shifting Ronchi tester with a square Ronchi ruling

The Ronchi test is one of the simplest and most effective methods used for evaluating and measuring aberrations. Employed in optical shops, its use is limited to qualitative analysis. Few methods in use today produce quantitative results. What follows are explained both the development and the guidelines for manufacturing a Ronchi tester based on quantitative analysis which also has the advantage to receive automatic input and output of data. In order to achieve this goal, phase shifting interferometry and a square Ronchi ruling with a variable intensity LED were used. It is important to note that with the set up described only one movement of the motor which supports the square ruling is needed to simultaneously obtain both the X and Y components of the wave front aberration.