This is time-domain OCT instrument that was built to
demonstrate novel and broad bandwidth light sources.
The system has the following features:
Broadband optics
The system is composed of bulk in air optics that
features ~300 nm of bandwidth and can accommodate
wavelengths from ~650 to 950 nm. In time domain OCT,
axial resolution is improves with increasing source
bandwidth. The system currently uses a commercial
SLD source that is centered at 855 nm and has 100
nm of bandwidth.
Focus tracking
The system is designed such that the coherence
gate and focus remain aligned as the objective
scans vertically. This ensures that the system
will have uniform resolution and sensitivity at
all depths within an ascan. The benefit of this
design is that the system can readily be used
for quantitative OCT studies.
High resolution
Using the current commercial SLD light source,
the system has an axial resolution of ~3.2 μm.
The lateral resolution (controlled by the NA
of the objective) is ~2.7 μm.
Spatially compact
The system is assembled onto a custom machined
aluminum plate that is attached to portable
breadboard that can be easily moved.
Minimized feedback to source through use of an isolator
Isolator improves signal to noise (SNR) by diverting the
returning fringe signal into the detector, thereby
preventing the fringe signal from returning to the source.
