Patent ID: 8922899

Claim:
A light combining system comprising: a first prism comprising a first entrance face enabled to receive first on-state light from a first DMD (digital micromirror device); a second prism comprising a second entrance face enabled to receive second on-state light from a second DMD; at least one interface between the first prism and the second prism enabled to receive the first on-state light and the second on-state light; and, a mirror at the at least one interface, enabled to transmit the first on-state light through the second prism and reflect the second on-state light in alignment with the first on-state light back through the second prism, each of respective angles formed by a normal of the mirror and each of the first on-state light and the second on-state light being less than a total internal reflection angle; a combination of respective back working distances of the first DMD and the second DMD and respective shapes of each of the first prism and the second prism selected such that: respective illumination paths and respective reflection paths of each of the first DMD and the second DMD do not interfere with each other, the respective illumination paths do not intersect the first prism and the second prism; and respective off-state paths of the first DMD and the second DMD do not intersect the first prism and the second prism.