US Patent 9068703 Light emitting diode illumination system

The present invention provides a light engine having four light sources. A combination of collimators, bandpass filters, dichroic mirrors, and other elements is operative to direct light from the light sources onto a main optical axis from where it may be focused into a light guide for transport to an instrument or device. Particular embodiments of the invention provide for computer control, intensity control, color control, and light source modulation. Additional embodiments include particular light sources including light pipes and lasers. The light engine provides white light having a high color rendering index and suitable for applications in microscopy, endoscopy, and/or bioanalytical instrumentation.