Infleqtion's quantum matter service, "Oqtant," equips users with remote access to quantum hardware for performing sophisticated research and enriching scientific education. Users can dynamically control reconfigurable optical fields applied to ultracold atoms, expanding their exploration of quantum mechanical phenomena. The platform offers tutorials, demos, and simulations to empower users to study and develop applications. In this paper, we introduce Oqtant and explore how users can leverage the platform for education and quantum research.
Confocal scanners are used to scan through a large sample depth necessary in both high throughput and high content screening applications. However, this scanning takes time and increases the cost and optical complexity of medical diagnostic devices. Here we present extended depth-of-field engineered point spread function (ePSF) technology, combined with our universal modular subsystem SPINDLE®, to enable precision extended-depth imaging that can be combined with high-content analysis (HCA), without the need for z scanning, and without trading off light or lateral resolution.
KEYWORDS: Optical coherence tomography, Data acquisition, Diagnostics, Volume rendering, 3D image processing, Image segmentation, Retinal scanning, 3D acquisition, Data centers, Signal detection
We report on the development of quantitative, reproducible diagnostic observables for age-related macular degeneration
(AMD) based on high speed spectral domain optical coherence tomography (SDOCT). 3D SDOCT volumetric data sets
(512 x 1000 x 100 voxels) were collected (5.7 seconds acquisition time) in over 50 patients with age-related macular
degeneration and geographic atrophy using a state-of-the-art SDOCT scanner. Commercial and custom software utilities
were used for manual and semi-automated segmentation of photoreceptor layer thickness, total drusen volume, and
geographic atrophy cross-sectional area. In a preliminary test of reproducibility in segmentation of total drusen volume
and geographic atrophy surface area, inter-observer error was less than 5%. Extracted volume and surface area of AMD-related
drusen and geographic atrophy, respectively, may serve as useful observables for tracking disease state that were
not accessible without the rapid 3D volumetric imaging capability unique to retinal SDOCT.
The onset of congenital heart disease (CHD) is believed to occur at very early stages of
development. Investigations in the initiation and development of CHD has been hampered by the
inability to image early stage heart structure and function, in vivo. Imaging small animals using
optical coherence tomography (OCT) has filled a niche between the limited penetration depth of
confocal microscopy and insufficient resolution from ultrasound. Previous demonstrations of
chick heart imaging using OCT have entailed excision of, or arresting the heart to prevent motion
artifacts. In this summary, we introduce SDOCT Doppler velocimetry as an enhancement of
Doppler OCT for in vivo measurement of localized temporal blood flow dynamics. With this
technique, dynamic velocity waveforms were measured in the outflow tract of the heart tube.
These flow dynamics correlate to a finite element model of pulsatile flow and may lead to a
further understanding of morphological influences on early heart development.
KEYWORDS: Heterodyning, Optical coherence tomography, Interferometry, Reflectors, Imaging systems, Demodulation, Image segmentation, Homodyne detection, Signal attenuation, Signal to noise ratio
Fourier domain (FD) techniques have increasingly gained attention in optical coherence tomography (OCT). This is primarily due to their demonstrated sensitivity of two to three orders of magnitude over conventional time-domain techniques. FDOCT images are subject to two primary sources of artifacts. First, a complex conjugate ambiguity arises because the Fourier transform of the real-valued spectral interferometric signal is Hermitian symmetric. This ambiguity leads to artifactual superposition of reflectors at positive and negative pathlength differences between the sample and reference reflectors. Second, noninterferometric and sample autocorrelation terms appear at dc, obscuring reflectors at zero pathlength difference. We show that heterodyne detection in swept-source OCT (SSOCT) enables the resolution of complex conjugate ambiguity and the removal of noninterferometric and autocorrelation artifacts. We also show that complex conjugate ambiguity resolution via frequency shifting circumvents falloff induced by finite source linewidth in SSOCT when samples are shifted to large pathlength differences. We describe an efficient heterodyne SSOCT design that enables compensation of power losses from frequency-shifting elements. Last, we demonstrate this technique, coupled with wavenumber triggering and electronic demodulation, for in vivo imaging of the human anterior eye segment.
Fourier domain techniques have increasingly gained attention in the optical coherence tomography field. This is mainly due to demonstrated sensitivities of two to three orders of magnitude greater than conventional time domain techniques. FDOCT images are plagued with two sources of ambiguity and artifact. First, complex conjugate ambiguity arises from the Fourier transform of the real-valued interferometric signal. This ambiguity causes a superposition of reflectors at positive and negative pathlength differences between the sample and reference reflectors. Secondly, the source spectral shape and sample autocorrelation terms appear at DC, there by obscuring reflectors at zero pathlength difference. In this paper, we show that heterodyne detection in swept-source OCT (SSOCT) allows for the resolution of complex conjugate ambiguity and the removal of spectral and autocorrelation artifacts. We show that frequency shifting of the reference arm optical field, by use of acousto-optic modulators, upshifts the cross-interferometric signal to a user-tunable electronic frequency that corresponds to a adjustable electronic pathlength mismatch between the interferometer arms. This electronic pathlength mismatching recenters the A-scan at an offset that can be far from DC, which effectively resolves the complex conjugate ambiguity problem. Additionally, spectral and autocorrelation terms still reside near DC, which allows them to be removed by high-pass filtering. We also show that complex conjugate ambiguity resolution via frequency shifting is immune to falloff induced by finite source linewidth in SSOCT.
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