To fit on the MPL spacecraft, it had to be compact, low mass and not use much power.
To be able to image the landing site at an interesting set of resolutions, it had to provide high resolution over a wide field of view.
To fit within the limited budget of the Mars Surveyor '98 Program, it had to cost a small fraction of what previous planetary mission imaging systems cost.
The mass and power and performance requirements were met with an innovative design which is described in subsequent pages.
The financial constraint was met by sharing the development costs of the MARDI electronics with those for the Mars Color Imager (MARCI), a camera system that was lost with the Mars Climate Orbiter in September 1999.
Art Credit: NASA/JPL/Caltech, annotated by Malin Space Science Systems