title: Null Hartmann and Ronchi-Hartmann tests.
abstract: Assuming the Ronchi and the Hartmann tests to be null tests, we were able to design special screens for each test that produce aligned straight fringes and a square array for the observed patterns. It also became clear that the screen filter and observing planes for both tests can be interchanged.
authors.forename: A
authors.initials: A
authors.lastname: Cordero-Davila
authors.forename: A
authors.initials: A
authors.lastname: Cornejo-Rodriguez
authors.forename: O
authors.initials: O
authors.lastname: Cardona-Nunez