It seems that there's more than meets the eye when it comes to the various Corps symbols in Green Lantern's lore. One Green Lantern artist revealed the secret history behind each sigil in the Emotional Spectrum.

Though the Green Lantern is the most well-known light-based organization in the DC Universe, it is but one fraction of a force known as the Emotional Spectrum. Millennia ago, the White Light of Creation was fractured into seven lights, each with their own emotional frequency. From passionate emotions like love to influential feelings such as fear, the Green Lantern universe got bigger with the Emotional Spectrum. In the same way that the Corps uses the Green Light of Will to protect the universe, every other organization in the Spectrum uses their lights for their own ends. And like the corps that preceded them, all other light-bearers have a unique symbol for their particular force.