Resources Contact Us Home
Fiber optic rotation sensor utilizing high birefringence fiber and having reduced intensity type phase errors

Image Number 5 for United States Patent #4881817.

A fiber optic rotation sensor using birefringent optical fiber includes an uncorrelating element, an equalizing element and a polarizer in the common input and output fiber portions of the sensor to reduce or eliminate the intensity type phase errors caused by interference between lightwaves originally in the same polarization mode on entry to the sensor loop that cross couple into another polarization mode. In the preferred embodiment, the uncorrelating element comprises a birefringence modulator and a length of birefringent fiber. The equalizing element comprises a birefringent fiber having a splice at which the axes of birefringence of the spliced portions of the fiber are positioned at relative to each other. The preferred embodiment also advantageously includes a birefringence modulator that introduces a time-varying birefringence into the optical fiber to introduce a deterministic phase error that reduces or eliminates amplitude type phase error caused by coherent interference between field components of light that are orthogonally polarized at the input of the sensor loop and that couple to the same polarization mode within the loop.

  Recently Added Patents
Method of treating a preceramic material
Method and apparatus for accessing and downloading information from the internet
System, apparatus and method for enabling/disabling display data channel access to enable/disable high-bandwidth digital content protection
Non-disruptive configuration of a virtualization controller in a data storage system
Discharge lamp lighting circuit
Scanning projection apparatus with tangential compensation
Method and apparatus for automatically controlling gas pressure for a plasma cutter
  Randomly Featured Patents
System and method for evaluating risk in fraud prevention
Stabilized video signal control loop
Network authentication system using individual services providers and an authentication server
Magnetic recording medium and the production thereof
Heat sink system
Method for manufacturing monolithic ceramic electronic components
Blind edgewise connector
Apparatus, system, and method for maximizing power system holdup time during loss of input power
Digital signatures for tangible medium delivery
Roller assembly for sliding screen door, and the like