Elasto-optical refractive index modulation due to photoacoustic initial pressure transients produced significant reflection of a probe beam when the absorbing interface had an appreciable difference. This effect was harnessed in new form non-contact optical resolution microscopy called remote sensing microscopy. A non-interferometric system architecture with low-coherence precludes detection surface oscillations and other phase-modulation phenomenon. The confocal scanned excitation ensure...

In this Letter, the capability of label-free fiber-based optical-resolution photoacoustic microscopy is demonstrated. This real-time imaging system takes advantage image-guide fibers and a unique fiber laser. The 800 μm consists 30,000 individual single-mode in bundle diode-pumped, pulsed Ytterbium laser utilized to perform up 600 kHz repetition rate. Phantom studies indicate 7 resolution. proposed setup keeps many powerful properties previous tabletop OR-PAM systems, but also offers...

In this paper a multi-wavelength optical-resolution photoacoustic microscopy (OR-PAM) system using stimulated Raman scattering is demonstrated for both phantom and in vivo imaging.A 1-ns pulse width ytterbium-doped fiber laser coupled into single-mode polarization maintaining fiber.Discrete Raman-shifted wavelength peaks extending to nearly 800 nm are generated with energies sufficient OR-PAM imaging.Bandpass filters used select imaging wavelengths.A dualmirror galvanometer was scan the...

Photoacoustic imaging techniques have been extensively developed for biomedical applications, including functional and molecular imaging, due in part to their high optical contrast, spatial resolution, non-ionizing properties. However, there are currently depth limitations cellular-resolution, optically focused photoacoustic microscopy systems. In addition, most common systems need be contact with the sample through an ultrasound medium. this work, by taking advantage of large initial...

Abstract Histopathological visualizations are a pillar of modern medicine and biological research. Surgical oncology relies exclusively on post-operative histology to determine definitive surgical success guide adjuvant treatments. The current workflow is based bright-field microscopic assessment histochemical stained tissues has some major limitations. For example, the preparation specimens for brightfield requires lengthy sample processing, delaying interventions days or even weeks....

In this paper a new class of optical Fabry-Perot-based ultrasound detectors using low acoustic impedance glancing angle deposited (GLAD) films is demonstrated. GLAD single-step physical vapor-deposition (PVD) technique used to fabricate porous nanostructured thin films. Using titanium dioxide (TiO(2)), transparent semiconductor with high refractive index (n = 2.4), the can be employed samples tailored nano-porosity, periodicities, and Q-factor reflectance spectra. The average lower than bulk...

Abstract Surgical oncologists depend heavily on visual field acuity during cancer resection surgeries for in-situ margin assessment. Clinicians must wait up to two weeks results from a pathology lab confirm post-operative diagnosis, potentially resulting in subsequent treatments. Currently, there are no clinical tools that can visualize diagnostically pertinent tissue information . Here, we present the first microscopy capable of non-contact label-free visualization human cellular morphology...

Abstract Histological visualizations are critical to clinical disease management and fundamental biological understanding. However, current approaches that rely on bright-field microscopy require extensive tissue preparation prior imaging. These processes both labor intensive contribute creating significant delays in feedback for treatment decisions can extend 2–3 weeks standard paraffin-embedded interpretation, especially if ancillary testing is needed. Here, we present the first...

Abstract Early diagnosis of ocular diseases improves the understanding pathophysiology and aids in accurate monitoring effective treatment. Advanced, multimodal imaging platforms play a crucial role visualization components provide clinicians with valuable tool for evaluating various eye diseases. Here, first time we present non-contact, multiwavelength photoacoustic remote sensing (PARS) microscopy swept-source optical coherence tomography (SS-OCT) in-vivo functional structural eye. The...

: Pathologists rely on histochemical stains to impart contrast in thin translucent tissue samples, revealing features necessary for identifying pathological conditions. However, the chemical labeling process is destructive and often irreversible or challenging undo, imposing practical limits number of that can be applied same section. Here we present an automated label-free whole slide scanner using a PARS microscope designed imaging thin, transmissible samples. Methods: Peak SNR in-focus...

In this paper a new generation of optical-resolution photoacoustic microscopy (OR-PAM) with wide range potential clinical applications is demonstrated. Using fast scanning mirrors, an image guide 30,000 fiber pixels, refocusing lens and unique probe we managed to reduce the footprint OR-PAM system from stationary table-top portable, 4 cm by 6 cm, weighing ~500 g tethered unit. The phantom studies show that handheld microscope able ~7 μm resolution. For in vivo images microvasculature Swiss...

In this Letter, multifocus optical-resolution photoacoustic microscopy is demonstrated using wavelength tuning and chromatic aberration for depth scanning. Discrete focal zones at several locations were created by refocusing light from a polarization-maintaining single-mode fiber pumped nanosecond laser. The laser parameters chosen to take advantage of stimulated Raman scattering (SRS) in the create multiwavelength output that could then be bandpass filtered. collimator lens objective are...

Optical-resolution photoacoustic microscopy (OR-PAM) is capable of achieving optical-absorption-contrast images with micron-scale spatial resolution. Previous OR-PAM systems have been frame-rate limited by mechanical scanning speeds and laser pulse repetition rate (PRR). We demonstrate imaging using a diode-pumped nanosecond-pulsed Ytterbium-doped 532-nm fiber PRR up to 600 kHz. Combined fast-scanning mirrors, our proposed system provides C-scan 3D acquisition frame 4 frames per second (fps)...

Abstract Malignant brain tumors are among the deadliest neoplasms with lowest survival rates of any cancer type. In considering surgical tumor resection, suboptimal extent resection is linked to poor clinical outcomes and lower overall rates. Currently available tools for intraoperative histopathological assessment require an average 20 min processing limited diagnostic quality guiding surgeries. Consequently, there unaddressed need a rapid imaging technique guide maximal tumors. Working...

Abstract In the past decades, absorption modalities have emerged as powerful tools for label-free functional and structural imaging of cells tissues. Many biomolecules present unique spectra providing chromophore-specific information on properties such chemical bonding, sample composition. As chromophores absorb photons absorbed energy is emitted (radiative relaxation) or converted to heat under specific conditions pressure (non-radiative relaxation). Modalities like fluorescence microscopy...

Optical imaging technologies have enabled outstanding analysis of biomedical tissues through providing detailed functional and morphological contrast. Leveraging the valuable information provided by these modalities can help us build an understanding tissues’ characteristics. Among various optical technologies, photoacoustic (PAI) coherence tomography (OCT) naturally complement each other in terms contrast mechanism, penetration depth, spatial resolution. The rich unique molecular-specified...

Abstract Accurate and fast histological staining is crucial in histopathology, impacting diagnostic precision reliability. Traditional methods are time-consuming subjective, causing delays diagnosis. Digital pathology plays a vital role advancing optimizing histology processes to improve efficiency reduce turnaround times. This study introduces novel deep learning-based framework for virtual using photon absorption remote sensing (PARS) images. By extracting features from PARS time-resolved...

We present a new integrated micro-endoscopy system combining label-free, fiber-based, real-time C-scan optical-resolution photoacoustic microscopy (F-OR-PAM) and high-resolution fluorescence for visualizing fluorescently labeled cellular components optically absorbing microvasculature simultaneously. With diode-pumped 532-nm fiber laser, the F-OR-PAM sub-system is able to reach resolution of ∼7 μm. The subsystem, which does not require any mechanical scanning, consists 447.5-nm-centered...

In this letter, the feasibility of label-free in vivo GRIN-lens optical resolution photoacoustic micro-endoscopy is demonstrated. An image guide with 100 000 single-mode fibers a 1.4 mm diameter bundle conjunction 0.29 pitch GRIN lens used order to transfer focused scanning spot through and refocus it into tissue. A high-repetition-rate (up 600 kHz) ytterbium fiber laser enable near real-time imaging capability. Phantom studies indicate 6 μm resolution. The system, ~2 working distance,...

Recently, a new noncontact reflection-mode imaging modality called photoacoustic remote sensing (PARS) microscopy was introduced providing optical absorption contrast. Unlike previous modalities, which rely on interferometric detection of probe beam to measure surface oscillations, the PARS technique detects initial pressures induced by pulsed laser at their origin monitoring intensity modulations reflected beam. In this paper, model describing temporal evolution from finite excitation pulse...

Wide-band hybrid amplifier is theoretically proposed using a series configuration of Thulium-doped fiber (TDFA) and Raman (FRA), which the similar type pump laser. The operating wavelength this covers bandwidth entire short band (S-band) region by combining gain spectrum TDFA FRA. theoretical varies from 20 to 24dB within 1460 1525nm in good agreement with experimental result. development reliable high-power diode lasers 1420nm range will make wide-band an interesting candidate for S-band...

In this Letter, reflection-mode optical resolution photoacoustic microscopy (OR-PAM) using glancing angle-deposited (GLAD) nanostructured Fabry-Perot interferometers (FPI) for in vivo applications is reported. GLAD a single-step physical vapor deposition (PVD) technique used to fabricate porous thin films. Using titanium dioxide, transparent semiconductor with high refractive index (n=2.4), the can be employed samples tailored nano-porosity, periodicities, and Q-factor reflectance spectra....

A fiber-tetherable non-contact photoacoustic remote sensing microscopy system capable of multiplex functional imaging is reported. By utilizing stimulated Raman scattering within an over-pumped polarization-maintaining single-mode optical fiber, rapid pulse-to-pulse switching (500 kHz) excitation spectral content demonstrated and utilized as a source. These acquisitions aim to reduce motion artifacts facilitate high frame rates appropriate for real-time feedback users. The characterized by...