Multiple Beam Fiber Optic Holography With Fringe Stabilization

Abstract

The use of fiber optics in the field of optical holography is described with emphasis on an experimental arrangement whereby several object and or reference beams are implemented simultaneously. This scheme enhances a holographic system's versatility by offering multiple illumination planes of any given object. Using several passive singlemode couplers and a closed loop phase stabilization technique, a multiple beam fiber optic holographic system with stable phase correlation among output fibers is presented. The feedback system incorporates a Michelson interferometer which detects relative phase fluctuations between output optical fibers. A servo controlled piezoelectric phase modulator automatically compensates for environmentally induced phase fluctuations inherent to a fiberized system. The resulting scheme is a very stable and highly versatile system suitable for remote holographic interferometric sensing and other applications where conventional holography techniques are impractical. Futhermore, new results on the ability to vary object and reference beam intensity ratios in a fiber optic holographic system will be discussed.