Folding converging light into a lightpipe

A front end unit for a light engine system comprising:

• a light source defined by a focal ratio for producing a high-flux converging beam of light along a first axis in free space and having a first cone angle;
• a lightpipe for inputting the converging beam of light and for outputting a relatively more spatially uniform beam of light along a second axis;
• a prism for folding the converging beam of light from the light source into the lightpipe;
• and
• a lens between the prism and the lightpipe for focusing the converging light into the lightpipe;
• wherein the prism a larger index of refraction than the free space, whereby the converging beam of light passing from the free space through the prism has a second cone angle less than the first cone angle, effectively increasing the focal ratio of the light source, and
• wherein the second cone angle effectively provides extra distance between the light source and the lightpipe to enable the beam of light to be folded into the lightpipe.

A front end unit for a light engine system comprising:

• a light source defined by a focal ratio for producing a high-flux converging beam of light along a first axis in free space and having a first cone angle;
• a lightpipe for inputting the converging beam of light and for outputting a relatively more spatially uniform beam of light along a second axis;
• a prism for folding the converging beam of light from the light source into the lightpipe;
• and
• a color wheel between the prism and the lightpipe;
• wherein the prism a larger index of refraction than the free space, whereby the converging beam of light passing from the free space through the prism has a second cone angle less than the first cone angle, effectively increasing the focal ratio of the light source, and
• wherein the second cone angle effectively provides extra distance between the light source and the lightpipe to enable the beam of light to be folded into the lightpipe.