A microscopic object detection system includes a collecting kit and a detection device. The collecting kit has a thin film for converting light into heat and is configured to be capable of holding a sample on the thin film. The detection device detects a plurality of microscopic objects in the sample by collecting the plurality of microscopic objects dispersed in the sample with the collecting kit. The detection device includes a laser module, an optical receiver, and a controller. The laser module emits a laser beam with which the collecting kit is irradiated. The optical receiver detects the laser beam from the sample held by the collecting kit and outputs a detection signal thereof. The controller calculates an amount of the plurality of microscopic objects collected in the sample based on a change of the detection signal over time.

A non-destructive method for chemical imaging with ˜1 nm to 10 μm spatial resolution (depending on the type of heat source) without sample preparation and in a non-contact manner. In one embodiment, a sample undergoes photo-thermal heating using an IR laser and the resulting increase in thermal emissions is measured with either an IR detector or a laser probe having a visible laser reflected from the sample. In another embodiment, the infrared laser is replaced with a focused electron or ion source while the thermal emission is collected in the same manner as with the infrared heating. The achievable spatial resolution of this embodiment is in the 1-50 nm range.

A method of analyzing a material (12) comprising at least one analyte, wherein analyte-wavelength-specific measurements are interspersed with reference measurements (80), and wherein response signals obtained for the reference measurements (80) are used for one or more of calibrating an excitation radiation source (26) for generating said excitation radiation, calibrating said detection device, recognizing a variation in the measurement conditions by comparing results of individual reference measurements (80), adapting the analyte measurement procedure (78) with respect to one or more of the entire duration thereof, the absolute or relative duration of analyte-wavelength-specific measurements for a given analyte-characteristic-wavelength, or terminating and/or restarting the analyte measurement procedure, and adapting the analysis carried out in the analyzing step.

Disclosed herein is an apparatus (10) for analyzing a material (12) comprising at least one analyte, said apparatus (10) comprising a measurement body (16) having a contact surface (14) suitable to be brought in thermal contact or pressure-transmitting contact with said material (12), an excitation radiation source configured for irradiating excitation radiation into the material (12) to be absorbed therein, and a detection light source for generating a detection light beam (22) travelling through at least a portion of said measurement body (16) or a component included in said measurement body, wherein said detection light beam is directed to be totally or partially reflected at said contact surface (14), wherein said contact surface (14) of the measurement body is curved in at least one principal direction in the area where the detection light beam (22) is reflected.

The present disclosure discloses a measurement method and an optical device for measuring an in-plane thermal conductivity of a sub-millimeter-scale sample. The optical device includes a first continuous-wave laser connected to a signal source; a second continuous-wave laser for outputting a detection laser, wherein a half-wave plate, a polarized beam splitter, a quarter-wave plate, a dichroic mirror, an objective lens, reflectors, a balanced photodetector, and a lock-in amplifier are sequentially arranged along an optical path of the detection laser, wherein the dichroic mirror is configured to allow transmission of the detection laser and reflection of the heating laser; the polarized beam splitter reflects part of the detection laser to the balanced photodetector and the detection laser reflected from the sample is reflected to the balanced photodetector, the balanced photodetector converts a laser signal into an electrical signal; the lock-in amplifier extracts an amplitude and a phase of the electrical signal.

Photoacoustic detecting device (1), intended to be applied, via a contact face (3), against a medium to be analysed, the device comprising: a hollow cavity (20) comprising a first aperture (22) produced in the contact face, the cavity being bounded by a containment shell (21) that extends around the first aperture; a pulsed or amplitude-modulated light source (10) configured to emit, in an emission spectral band (Δλ), an incident light wave (11) through the cavity (20) to the first aperture; an acoustic transducer (28) linked to the cavity and configured to detect a photoacoustic wave (12) extending through the cavity. The photoacoustic detecting device is optimized to increase the amplitude of the photoacoustic wave detected by the acoustic transducer.

A method and an interferometric device for spectroscopically or spectrometrically examining a sample, comprising: a) generating a laser beam having a wavelength, b) splitting the laser beam into a measurement beam and a reference beam, c) interacting the sample with the measurement beam, d) interacting a reference with the reference beam, e) overlaying the measurement beam and the reference beam, f) detecting a first output beam, g) detecting a second output beam, h) forming a differential signal between the first output signal and the second output signal, i) controlling the differential signal to a predefined target value, j) determining a refractive index of the sample from the adjustment of the phase difference between the measurement beam and the reference beam, k) repeating steps a) to j) for additional wavelengths of the laser beam.

A method of microscopy is disclosed. The method comprises directing a pulse of a pump optical beam to form an optical spot on a substance and measuring changes in a temperature-dependent or photo-excited property of the substance. The method further comprises analyzing the measured changes to distinguish between information pertaining to the property at a portion of the spot, and information pertaining to the property at other portions of the spot. A largest diameter of the portion of the spot is optionally and preferably less than a central wavelength of the pump optical beam.

Systems and methods are provided for performing thermophotonic imaging using cross-correlation and subsequent time-gated truncation. Photothermal radiation is detected with an infrared camera while exciting a sample with a chirped set of incident optical pulses and time-dependent photothermal signal data is processed using a method that involves performing cross-correlation and subsequent time-gated truncation. The post-cross-correlation truncation method results in depth-resolved images with axial and lateral resolution beyond the well-known thermal-diffusion-length-limited, depth-integrated nature of conventional imaging modalities. An axially resolved photothermal image sequence can be obtained, capable of reconstructing three-dimensional visualizations of photothermal features in wide classes of materials.

A method of measuring thermal conductivity of a material includes focusing a modulated pump laser beam having a modulation frequency that induces a cyclical steady-state temperature rise at a spot of a material, focusing a CW probe laser beam at the spot and generating a reflected probe beam reflected from the spot on the material, the reflected probe beam having a magnitude of a reflectance signal as a function of the temperature of the material and being periodic corresponding to the cyclical temperature rise, measuring the magnitude of the reflectance signals of the reflected probe beam, and determining the thermal conductivity by fitting the power of the pump beam and the measured magnitude of the reflectance signal to a thermal model which is a function of a thermal conductivity of the material relating the radial heat flux to the temperature rise.