Some all-spherical designs are presented that are variations of the positive-negative-positive triplet with the stop at the
front. Examples include a compact wide angle (60° field of view) near-telecentric lens, as well as super-achromatic,
telecentric lenses for the visible to infrared (450-1000nm or 450-2300 nm) and mid-wave and thermal infrared. This
design form, loosely thought of as a boosted version of the rear landscape lens, has provided a useful optimization starting
point for a variety of designs with different requirements.