Abstract:
PROBLEM TO BE SOLVED: To provide a frequency swept laser light source to be used for TEFD-OCT (time-encoded Furrier domain optical coherence tomography) imaging, which achieves a long coherence length of the light source.SOLUTION: The frequency swept laser light source to be used for TEFD-OCT imaging includes an integrated clock subsystem on an optical bench including a laser light source. The clock subsystem generates a frequency clock signal as the optical signal is tuned over the scan band. The laser light source further includes a cavity extender in its optical cavity between a tunable filter and gain medium to increase an optical distance between the tunable filter and the gain medium in order to control the location of laser intensity pattern noise. The laser also includes a fiber stub that allows for control over the cavity length while controlling birefringence in the cavity.
Abstract:
An integrated swept wavelength tunable optical source uses a narrowband filtered broadband signal with an optical amplifier and self-tracking filter. This source comprises a micro optical bench, a source for generating broadband light, a tunable Fabry Perot filter, installed on the bench, for spectrally filtering the broadband light from the broadband source to generate a narrowband tunable signal, an amplifier, installed on the bench, for amplifying the tunable signal. The self-tracking arrangement is used where a single tunable filter both generates the narrowband signal and spectrally filters the amplified signal. In some examples, two-stage amplification is provided. The use of a single bench implementation yields a low cost high performance system. For example, polarization control between components is no longer necessary.
Abstract:
A frequency swept laser source for TEFD-OCT imaging includes an integrated clock subsystem on the optical bench with the laser source. The clock subsystem generates frequency clock signals as the optical signal is tuned over the scan band. Preferably the laser source further includes a cavity extender in its optical cavity between a tunable filter and gain medium to increase an optical distance between the tunable filter and the gain medium in order to control the location of laser intensity pattern noise. The laser also includes a fiber stub that allows for control over the cavity length while also controlling birefringence in the cavity.