Abstract: A spectroscopy and microscopy system and method include a source of pulsed infrared light generating pulsed infrared excitation light for exciting a sample, such that the pulsed infrared light selectively heats the sample by absorption of the pulsed infrared light and allows the sample to cool. A source of probe light generates probe light for illuminating the sample. A detection element detects a signal indicative of selective heating of the sample by the excitation light. A processor receives the signal indicative of the selective heating of the sample, computes a time rate of local temperature rise in the sample to obtain instantaneous absorption in the sample, and, using the instantaneous absorption, generates a spectrum related to the sample.

Abstract: Systems and methods implement of high-speed delay scanning for spectroscopic SRS imaging characterized by scanning a first pulsed beam across a stepwise reflective surface (such as a stepwise mirror or a reflective blazed grating) in a Littrow configuration to generate near continuous temporal delays relative to a second pulsed beam. Systems and methods also implement deep learning techniques for image restoration of spectroscopic SRS images using a trained encoder-decoder convolution neural network (CNN) which in some embodiments may be designed as a spatial-spectral residual net (SS-ResNet) characterized by two parallel filters including a first convolution filter on the spatial domain and a second convolution filter on the spectral domain.

Abstract: A stimulated Raman photothermal (SRP) microscope for imaging a sample. A first optical source without an optical resonator emits a pump beam. A second optical source emits an intensity-modulated Stokes beam. The Stokes beam is combined with the pump beam to form a combined beam. The combined beam is directed to the sample to induce a thermal effect caused by the stimulated Raman process. A third optical source emits a probe beam, the probe beam is directed to the sample. An optical detector detects modulation of the probe beam after modulation by the sample to measure an SRP signal. Because noise in the pump and Stokes beam do not significantly effect the measurements from the probe beam, these beams can use a high-powered optical parametric amplifier (OPA) source for improved sensitivity and imaging speed compared to SRP microscopes using an optical parametric oscillator (OPO) source.

Abstract: A stimulated Raman photothermal (SRP) microscope for imaging a sample. A first optical source without an optical resonator emits a pump beam. A second optical source emits an intensity-modulated Stokes beam. The Stokes beam is combined with the pump beam to form a combined beam. The combined beam is directed to the sample to induce a thermal effect caused by the stimulated Raman process. A third optical source emits a probe beam, the probe beam is directed to the sample. An optical detector detects modulation of the probe beam after modulation by the sample to measure an SRP signal. Because noise in the pump and Stokes beam do not significantly effect the measurements from the probe beam, these beams can use a high-powered optical parametric amplifier (OPA) source for improved sensitivity and imaging speed compared to SRP microscopes using an optical parametric oscillator (OPO) source.

Abstract: A spectroscopy and microscopy system and method include a source of pulsed infrared light generating pulsed infrared excitation light for exciting a sample, such that the pulsed infrared light selectively heats the sample by absorption of the pulsed infrared light and allows the sample to cool. A source of probe light generates probe light for illuminating the sample. A detection element detects a signal indicative of selective heating of the sample by the excitation light. A processor receives the signal indicative of the selective heating of the sample, computes a time rate of local temperature rise in the sample to obtain instantaneous absorption in the sample, and, using the instantaneous absorption, generates a spectrum related to the sample.

Abstract: A short-wave infrared photothermal (SWIP) microscopy system and method for vibrational imaging of a sample generates shortwave infrared excitation light probe light. The excitation light and the probe light are combined to generate a combined beam, which is focused to generate a focused combined beam, which is directed onto the sample to obtain a SWIP signal generated by absorption-induced thermo-optic selective heating of the sample. The SWIP signal is collected through an aperture in a condenser and detected.

Abstract: Systems and methods for detecting photothermal effect in a sample are described herein. In these systems and methods, a pump source is configured to generate a pump pulse train, a probe source is configured to generate a probe pulse train and is synchronized with the pump pulse train, and a camera collects the resulting data. The camera is configured to collect a first signal corresponding to a hot frame, wherein the hot frame includes visible probe beam as modified by a pump beam and a second signal corresponding to a cold frame, wherein the cold frame includes visible probe beam that has not been modified by a pump beam. A processor can subtract the second signal from the first signal to detect the photothermal effect.

Abstract: A stimulated Raman photothermal (SRP) microscope for imaging a sample. A first optical source omits an intensity-modulated pump beam. A second optical source omits an intensity-modulated Stokes beam. The Stokes beam is combined with the pump beam to form a combined beam. The combined beam is directed to the sample to induce a thermal effect caused by the stimulated Raman process. A third optical source emits a probe beam, the probe beam is directed to the sample. An optical detector detects modulation of the probe beam after modulation by the sample to measure an SRP signal.

Abstract: A system for neuromodulation includes a split-ring resonator (SRR) comprising a resonance circuit, the SRR being implantable in a cranial target site and a source of microwave signals, wherein the microwave signals are deliverable wirelessly to couple with the SRR to produce a localized electrical field, wherein the localized electrical field inhibits one or more neurons at the cranial target site with submillimeter spatial precision.

Abstract: A mid-infrared photothermal microscopy system images a sample. A mid-infrared optical source generates a mid-infrared beam which is directed along a first optical path to reach the substrate on a first side and heat the sample. A probe light source generates a probe light which is directed along a second optical path to reach the substrate on a second side and illuminate the sample. A first laser scanner is positioned along the first optical path and configured to rotate to redirect light and scan the sample with the mid-infrared beam. A second laser scanner is positioned along the second optical path and configured to rotate to redirect light and scan the sample with the probe light. The laser scanners each include at least one mirror driven to rotate such that the mid-infrared beam and the probe light scan the sample synchronously.

Abstract: A short-wave infrared photothermal (SWIP) microscopy system and method for vibrational imaging of a sample generates shortwave infrared excitation light probe light. The excitation light and the probe light are combined to generate a combined beam, which is focused to generate a focused combined beam, which is directed onto the sample to obtain a SWIP signal generated by absorption-induced thermo-optic selective heating of the sample. The SWIP signal is collected through an aperture in a condenser and detected.

Abstract: Microscopic analysis of a sample includes a fluorescent dye disposed within the sample. A mid-IR optical source generates a mid-infrared beam, which is directed onto the sample to induce a temperature change by absorption of the mid-infrared beam. An optical source generates a probe beam directed to impinge on the sample. A detector detects fluorescent emissions from the sample when the probe beam impinges on the sample. A data acquisition and processing system acquires and processes the detected fluorescent emissions from the sample to: (i) generate a signal indicative of infrared absorption by the sample, (ii) generate a signal indicative of temperature in the sample based on the signal indicative of infrared absorption by the sample, (iii) generate an image of the sample using the signal indicative of temperature in the sample.

Abstract: A stimulated Raman photothermal (SRP) microscope for imaging a sample. A first optical source omits an intensity-modulated pump beam. A second optical source omits an intensity-modulated Stokes beam. The Stokes beam is combined with the pump beam to form a combined beam. The combined beam is directed to the sample to induce a thermal effect caused by the stimulated Raman process. A third optical source emits a probe beam, the probe beam is directed to the sample. An optical detector detects modulation of the probe beam after modulation by the sample to measure an SRP signal.

Abstract: A wide-field bond-selective optical coherence tomography (OCT) system and method for imaging a sample includes generating infrared light and directing the infrared light onto the sample to selectively heat the sample. Probe light is also directed onto the sample. A first actuator provides sample depth scanning with respect to a first objective in a reference arm of the system, and a second actuator provides sample depth scanning with respect to a second objective in a sample arm of the system. A detection system receives scattered probe light reflected from the sample. A change in the received probe light from the sample that is indicative of absorption of infrared light.

Abstract: A wide-field microscopy system and method for imaging a sample include directing infrared light onto the sample to selectively heat the sample. Probe light is also directed onto the sample. An objective collects the probe light after it interacts with the sample. The collected probe light is detected at a detector. A relative distance between the objective and sample is adjusted to introduce an optical defocus enhancement to enhance detection of a change in detected probe light that is indicative of infrared absorption by the sample.

Abstract: Microscopic analysis of a sample includes a fluorescent dye disposed within the sample. A mid-IR optical source generates a mid-infrared beam, which is directed onto the sample to induce a temperature change by absorption of the mid-infrared beam. An optical source generates a probe beam directed to impinge on the sample. A detector detects fluorescent emissions from the sample when the probe beam impinges on the sample. A data acquisition and processing system acquires and processes the detected fluorescent emissions from the sample to: (i) generate a signal indicative of infrared absorption by the sample, (ii) generate a signal indicative of temperature in the sample based on the signal indicative of infrared absorption by the sample, (iii) generate an image of the sample using the signal indicative of temperature in the sample.

Abstract: Microscopic analysis of a sample includes a system using dark-field illumination. A mid-IR optical source generates a mid-infrared beam, which is directed onto the sample to induce a temperature change by absorption of the mid-infrared beam. A visible light source generates a light illuminating the sample on a substrate and creating a scattered field and a reflected field along a collection path of the system. A pupil mask is positioned along the collection path to block the reflected field while allowing the scattered field to pass therethrough. A camera is positioned at an end of the collection path to collect the scattered field and generate a dark-field image of the sample.

Abstract: Systems and methods are provided for performing photothermal dynamic imaging. An exemplary method includes: scanning a sample to produce a plurality of raw photothermal dynamic signals; receiving the raw photothermal dynamic signals of the sample; generating a plurality of second signals by matched filtering the raw photothermal dynamic signals to reject non-modulated noise; and performing an inverse operation on the second signals to retrieve at least one thermodynamic signal in a temporal domain.

Abstract: Methods of the present invention comprise photoinactivation of catalase in combination with low-concentration peroxide solutions and/or ROS generating agents to provide antibacterial effects.

Abstract: An example microscope includes a pump laser for providing a first illumination to a sample. A laser array provides a second illumination to the sample. The laser array may include a plurality of laser elements, each providing oblique illuminations to the sample. An illumination collecting source collects the first illumination and the second illumination from the sample. The illumination collecting source may capture transient 3D refractive index (RI) variations in the sample due to the first illumination and second illumination.