Polaroid Corporation a "juggernaut of innovation", in many respects Polaroid was the Apple of its time with a "leader in Edwin Land, a scientist who guided the company as the founding CEO for four decades". Polaroid’s initial market was in polarized sunglasses — spawned from Land’s self-guided research in light polarization. Land, having completed his freshman year at Harvard University, left to pursue this market, resulting in Polaroid's birth. Land later returned to Harvard to continue his research. Polaroid, owning patents to its polarizer technology, got its start by employing polarization in products that included 3-D movies and glare-reducing goggles for dogs.
Polaroid Swinger correctly. Earlier models also displayed the word "NO" when not properly adjusted, while later units used only the YES indicator. The Swinger also included a built-in flashgun for AG-1 flashbulbs. The Swinger used Polaroid's 20-Series roll film, which was the first Polaroid roll film to develop outside the camera. Variants included the Model M-15 "Swinger Sentinel" (the Swinger II in non-US markets), which was a cheaper Swinger without the built-in flash, and the Model 3000 "Big Swinger", which used 100-Series pack film instead of the old-style picture rolls. The Swinger name was also used on several international-market Polaroid cameras in