It is an extension of the Hartmann test. In the Hartmann test, a screen with holes is put in front of the primary mirror, and a photographic plate is placed near the telescope focus to record a pattern of spots. An analysis of the position of these spots gave the aberrations of the telescope.

Since it is inconvenient to put a screen in front of the mirror every time the test has to be made, Shack in 1980 suggested that the test could be done on the transferred pupil, by putting a lenslet array instead of a screen, which could be of a much smaller size. This also allowed the use of CCD detectors, making the process of recording the SH pattern and its subsequent analysis much easier.

The SH method is now standard on most telescopes, and can be used both in the off-line and on-line mode (active optics).