Synthesis of pure white color and its equal power, equal chromatic splitting through a novel 3x3 fiber optic visible multiplexer

Fiber optic engine for micro projection display

A novel compact optical engine for a micro projector display is experimentally demonstrated, which is composed of RGB light sources, a tapered 3 x 1 Fiber Optic Color Synthesizer (FOCS) along with a fiberized ball-lens, and a two dimensional micro electromechanical scanning mirror. In the proposed optical engine, we successfully employed an all-fiber beam shaping technique combining optical fiber taper and fiberized ball lens that can render a narrow beam and enhance the resolution of the screened image in the far field. Optical performances of the proposed device assembly are investigated in terms of power loss, collimating strength of the collimator assembly, and color gamut of the output.

Acousto-optic control of speckle contrast in multimode fibers with a cylindrical piezoelectric transducer oscillating in the radial direction

We report efficient acousto-optic control of speckle contrast at the output of multimode fibers (MMFs) using a cylindrical piezoelectric transducer (PZT) vibrating in the radial direction. With appropriate packaging of an MMF around the PZT, periodic stretching and subsequent intensity modulation were achieved over the wound fiber to result in time-averaged smoothing of the output within a short time. It was experimentally confirmed that light passed through the vibrating PZT-fiber assembly maintains the virtually partial coherence irrespective of the guide length and power splitting. Real-time vibration-off/on movies were presented, and their single-frame excerpts were analyzed.

Design and fabrication of white light emitting diodes with an omnidirectional reflector

This study investigates white light emitting diodes (LEDs), packaged with an omnidirectional reflector (ODR) and UV LED of 378 nm. The current work designs an ODR to solve the problems of UV leak and low phosphors conversion efficiency with a thin film structure of S/(HLH)n/air modified from a quarter-wave stack. Since an ODR is a perfect dielectric mirror for UV light, the UV leak can be eliminated and recycled to enhance phosphors conversion efficiency. By measuring the emission spectrum of a white LED with an ODR, the orientation distribution of the color properties, and the radiation power, the current study did not detect any UV leak. The average luminous intensity enhancement is 15%.