Time-of-flight three-dimensional (3D) imaging has applications that range from industrial inspection to motion tracking. Depth is recovered by measuring the round-trip flight time of laser pulses, typically using collection optics several centimeters in diameter. We demonstrate near–video-rate 3D through multimode fibers with a total aperture hundred micrometers. implement aberration correction wavefront shaping synchronized pulsed source and scan scene at ~23,000 points per second. image...

Light transport in a highly multimode fiber exhibits complex behavior space, time, frequency and polarization, especially the presence of mode coupling. The newly developed techniques spatial wavefront shaping turn out to be suitable harness such enormous complexity: light modulator enables precise characterization field propagation through fiber, by adjusting incident it can accurately tailor transmitted pattern, temporal profile polarization state. This unprecedented control leads...

Abstract Light-based in-vivo brain imaging relies on light transport over large distances of highly scattering tissues. Scattering gradually reduces contrast and resolution, making it difficult to reach structures at greater depths even with the use multiphoton techniques. To deeper, minimally invasive endo-microscopy techniques have been established. These most commonly exploit graded-index rod lenses enable a variety modalities in head-fixed freely moving animals. A recently proposed...

Progress in neuroscience constantly relies on the development of new techniques to investigate complex dynamics neuronal networks. An ongoing challenge is achieve minimally-invasive and high-resolution observations activity vivo inside deep brain areas. A perspective strategy utilise holographic control light propagation media, which allows converting a hair-thin multimode optical fibre into an ultra-narrow imaging tool. Compared current endoscopes based GRIN lenses or bundles, this concept...

Digital micro-mirror devices (DMDs) have recently emerged as practical spatial light modulators (SLMs) for applications in photonics, primarily due to their modulation rates, which exceed by several orders of magnitude those the already well-established nematic liquid crystal (LC)-based SLMs.This, however, comes at expense limited depth and diffraction efficiency.Here we compare beam-shaping fidelity both technologies when applied control complex environments, including an aberrated optical...

The dynamic spatial control of light fields is essential to a range applications, from microscopy optical micro-manipulation and communications. Here we describe the use single digital micro-mirror device (DMD) generate rapidly switch vector beams with spatially controllable intensity, phase polarisation. We demonstrate local over linear, elliptical circular polarisation, allowing generation radially azimuthally polarised Poincaré beams. All these can be switched at rates up 4kHz (limited...

Light transport through a multimode optical waveguide undergoes changes when subjected to bending deformations. We show that waveguides with perfectly parabolic refractive index profile are almost immune bending, conserving the structure of propagation-invariant modes. Moreover, we transmission matrix parabolic-index fibers due can be expressed only two free parameters, regardless how complex particular deformation is. provide detailed analysis experimentally measured matrices commercially...

Holographic wavefront manipulation enables converting hair-thin multimode optical fibres into minimally invasive lensless imaging instruments conveying much higher information densities than conventional endoscopes. Their most prominent applications focus on accessing delicate environments, including deep brain compartments, and recording micrometre-scale resolution images of structures in close proximity to the distal end instrument. Here, we introduce an alternative 'farfield' endoscope,...

Holographic, multimode fibre (MMF) based endoscopes envision high-quality in-vivo imaging inside previously inaccessible structures of living organisms, amongst other perspective applications. Within these instruments, a digital micro-mirror device (DMD) is deployed in order to holographically synthesise light fields which, after traversing the fibre, form foci at desired positions behind distal facet. When applied various modalities, purity and sharpness achieved are determinant for...

Holographic multimode fibre endoscopes have recently shown their ability to unveil and monitor deep brain structures with sub-micrometre resolution, establishing themselves as a minimally-invasive technology promising applications in neurobiology. In this approach, holographic control of the input light field entering fibres is achieved by means wavefront shaping, usually treating complex medium. contrast other unpredictable highly scattering media, feature symmetries strong correlations...

In-vivo microendoscopy in animal models became a groundbreaking technique neuroscience that rapidly expands our understanding of the brain. Emerging hair-thin endoscopes based on multimode fibres are now opening up prospect ultra-minimally invasive neuroimaging deeply located brain structures. Complementing these advancements with methods functional imaging and optogenetics, as well extending its applicability to awake motile animals constitute most pressing challenges for this technology....

SignificanceHair-thin multimode optical fiber-based holographic endoscopes have gained considerable interest in modern neuroscience for their ability to achieve cellular and even subcellular resolution during in-vivo deep brain imaging. However, the application of fibers freely moving animals presents a persistent challenge as it is difficult maintain optimal imaging performance while fiber undergoes deformations.AimWe propose solution challenging applications with capability high spatial...

In imaging geometries, which employ wavefront-shaping to control the light transport through a multi-mode optical fibre (MMF), this terminal hair-thin component acts as minimally invasive objective lens, enabling high resolution laser-scanning fluorescence microscopy inside living tissues at depths hardly accessible by any other light-based technique. Even in most advanced systems, diffraction-limited foci scanning object across focal plane are contaminated stray signal carrying typically...

Computer-controlled spatial modulation of coherent light has enabled multiple new ways imaging through complex media. MEMS-based digital micromirror devices (DMDs) employed as modulators present considerably higher display frame rates compared to the popular alternative based on liquid crystal technology. For a progress beyond laboratory conditions, hologram projected with DMD needs remain time-invariant after wavefront correction. The thermal load when operating at highest is one main...

Abstract There has been a tremendous effort in modern microscopy towards miniaturisation and fibre-based technology, driven by the need to access hostile or difficult environments situ vivo. Most of these rely on reducing size endoscopes based fibre-optic bundles, systems incorporating microfabricated lenses. Recently, use standard multimode optical fibres for lensless become possible mainly due advances holographic beam shaping. This article reviews methods techniques behind this progress...

SignificanceOver more than 300 years, microscopic imaging keeps providing fundamental insights into the mechanisms of living organisms. Seeing structures beyond reach free-space light-based microscopy, however, requires dissection tissue—an intervention seriously disturbing its physiological functions. The hunt for low-invasiveness tools has led a growing community physicists and engineers realm complex media photonics. One activities represents exploiting multimode optical fibers (MMFs) as...

Holographic multimode fibre endoscopes have recently shown their promising potential as a minimally invasive imaging tool, particularly in the field of neurobiology. Currently, resolution is limited by diffraction, constrained relatively low numerical aperture fibres used (typically less than 0.4). Overcoming diffraction-limit barrier would open new possibilities for detailed observation dendritic spines and motility in-vivo. In this presentation we demonstrate pulsed STED microscopy...

Acoustic sensitivity of the novel negative curvature hollow core fiber (NCHCF) has been investigated both experimentally and theoretically. The normalized response NCHCF is shown to be 6 dB higher than in case conventional fiber.

Digital micro-mirror devices (DMDs) have recently emerged as practical spatial light modulators (SLMs) for applications in photonics, primarily due to their modulation rates, which exceed by several orders of magnitude those the already well-established nematic liquid crystal (LC)-based SLMs. This, however, comes at expense limited depth and diffraction efficiency. Here we compare beam-shaping fidelity both technologies when applied control complex environments, including an aberrated...

We have investigated the mode-lock operation from a semiconductor optical amplifier (SOA) gain chip in ring fibre configuration. At lower pump currents, laser generates dark soliton pulses both at fundamental repetition rate of 39 MHz and supports up to 6 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup> harmonic order corresponding 234-MHz with an output power ~2.1 mW. higher can be switched between bright, concurrent bright generation regimes.

The previous five years have shown a rapidly growing interest in digital micromirror device (DMD) as spatial light modulator for complex photonics applications, primarily due to their high switching rate, allowing control the at speed unreachable most current modulators based on liquid crystals (LC-SLM). Here we demonstrate common technique aberration correction implemented both/each DMD and LC-SLM devices alternatively. experiments been performed focusing through multimode optical fibre....

Fibre-based optical tweezers typically rely on engineered fibre terminations yielding limited flexibility in number and positioning of trap sites. Here, we demonstrate holographic delivered by a lensless, high-NA multimode with full control multiple independently all directions.

Multimode optical fibres can be employed as an alternative to traditional endoscopes through high-speed wavefront shaping. Using a pulsed source and time of flight we achieve far field 3D imaging fibres.