We present a newly developed single mode fiber based swept source polarization sensitive optical coherence tomography system using a single input state at 1040 nm. Two non-polarizing fiber based beam splitters are combined to form a Mach-Zehnder interferometer, while two polarizing beam splitters are used to obtain a polarization sensitive detection. Both types of beam splitters solely feature ...

We describe fiber-based quadrature low-coherence interferometers that exploit the inherent phase shifts of 3 x 3 and higher-order fiber-optic couplers. We present a framework based on conservation of energy to account for the interferometric shifts in 3 x 3 interferometers, and we demonstrate that the resulting interferometers provide the entire complex interferometric signal instantaneously in...

A single-longitudinal-mode (SLM) thulium-doped fiber laser, based on an eye-shaped passive dual-ring filter, is designed and constructed. The compound cavity consisting of four couplers used to increase the longitudinal mode spacing, its performance numerically analyzed in detail. homemade uniform Bragg grating serves as a wavelength selection device saturable absorber further suppress intense ...

It is well known that the sensitivity of the LIGO interferometers decreases at higher frequencies and indeed, for an “optimally” oriented g.w. (i.e. with the propagation vector normal to the plane of the arms) vanishes at the free spectral range (fsr) frequency ν = ν0 = c/2L. However “optimal” orientation is a special case and when averaged over directions of incidence and polarization of the g...

We present a noise estimation and subtraction algorithm capable of increasing the sensitivity heterodyne laser interferometers by one order magnitude. The interferometer is specially designed for dynamic measurements test mass in application sub-Hz inertial sensing. A floor 3.31×10−11m/Hz at 100 mHz achieved after applying our to benchtop prototype that showed level 2.76×10−10m/Hz when tested v...

Abstract The high-precision phase extraction method directly determines the final measurement performance of heterodyne laser interferometer. This paper proposes a digital quadrature phase-locked (DQPL) with sub-nanometer precision based on FPGA hardware and compiled LABVIEW platform. DQPL can accurately extract difference two optical signals in validity stability have been verified by simulati...