Typically for longer imaging ranges the sampling rate and data transfer will become a limiting factor that must be considered in engineering design. The imaging range further depends on the optical detector bandwidth and data acquisition (DAQ). There are certain regions such as 1060, 13 nm which are optimal due to dip in the water absorption. This is strongly wavelength depended why for imaging of tissue with high water content lower wavelength is chosen, and for tissue with low water content longer wavelength is chosen. OCT provide very high resolution in the micrometer range with limited penetration depth in the millimeter range. Specific to OCT is the consideration of the optical penetration which is limited by absorption and scattering. There are several other areas where OCT is an active research area or commercialized. ![]() ![]() OCT is especially useful in Ophthalmic imaging since other methods such as ultrasound, x-ray, positron imaging and magnetic resonance imaging (MRI) are not convenient due to the invasive nature, high cost and large size. Better sweep stability enabling high-quality imaging and phase-sensitive OCT (e.g., angiography).Less constraints on sample positioning and simplified design of scanning equipment.Long imaging range by its inherently long coherence length of more than 50 mm.High sweep rates for wide-field, video-rate, and high-resolution 3D imaging.Center wavelength of 1060 nm for deeper penetration into the eye (choroid imaging).OCTLIGHT´s Caliper technology has the following features and benefits with Ophthalmic OCT Full 3D wide-field OCT scans have the potential to become a comprehensive tool for mapping out all the layers of the eye with better results in diagnosis and treatment. This allows the doctor to see a cross-section of the retina of the eye where the sharp vision is formed. The eye specialist can perform non-invasive optical biopsies using the OCT technique. OCT is widely adopted within eye care where it is the gold standard for in vivo imaging of the retina. This cross-sectional image is also referred to as tomography. © 1999 Society of Photo-Optical Instrumentation Engineers.Optical Coherence Tomography (OCT) is a technology for non-invasive optical imaging of tissue. However, as presently implemented, ZAP tends to blur sharp boundaries between image features. The results show that ZAP reduces speckle contrast in regions where scatterer density is high and expands the range of gray values in the image. After demonstrating its speckle-correction properties mathematically and in numerical simulations, we apply ZAP to OCT images of living skin. A speckle-reduction technique that works in the complex domain, called the zero-adjustment procedure (ZAP), is investigated as an example of complex-domain processing. We describe an OCT system that incorporates a quadrature-demodulation scheme for accurate recording of the phase and amplitude of OCT signals from single or multiple detectors. Processing the partially coherent OCT signals in the complex domain provides the opportunity to correct phase aberrations responsible for speckle noise in OCT images. ![]() This study explores the idea of recording and processing the phase of the OCT interference signal before calculation of the magnitudes for display. Computation of the absolute magnitude of the signal for measurement of the envelope is a nonlinear process that destroys phase information. In optical coherence tomography (OCT), images are usually formed from the envelope of the measured interference signal.
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