A Raman spectroscopy method includes acquiring a first spectrum of a sample by performing exposure over a first time period in Raman spectroscopy of the sample, calculating a first Raman signal intensity of the first spectrum acquired, calculating a second time period from the first time period based on the ratio of the first Raman signal intensity calculated to a second Raman signal intensity that is a Raman signal intensity required for the Raman spectroscopy, the second time period being an exposure time period required for acquiring the second Raman signal intensity, and acquiring a second spectrum of the sample by performing exposure over the second time period calculated.

Systems and methods are provided for measuring the mechanical properties of ocular tissue, such as the lens or corneal tissue, for diagnosis as well as treatment monitoring purposes. A laser locking feedback system is provided to achieve frequency accuracy and sensitivity that facilitates operations and diagnosis with great sensitivity and accuracy. Differential comparisons between eye tissue regions of a patient, either on the same eye or a fellow eye, can further facilitate early diagnosis and monitoring.

The present disclosure provides a scanning probe, a method and an apparatus for manufacturing the scanning probe. The scanning probe includes a base and a micro-tip disposed on an end of the base, wherein at least a section of the micro-tip comprises a lateral surface with a concavely curved generatrix. In the method, an end of a probe precursor is immersed in a corrosive solution by having a length direction of the probe precursor inclined with a liquid surface of the corrosive solution. The probe precursor is corroded by the corrosive solution while a corrosion current of the corroding is monitored. The probe precursor is moved away from the corrosive solution after a magnitude of the corrosion current has a plunge. The apparatus includes a container containing the corrosive solution, and a driving device configured to move the probe precursor in the container through a fastener.

A method for enhancement of spontaneous Raman scattering (SRS) from gases comprising a multimode blue laser diode which receives feedback from a near concentric bidirectional multipass cavity in such a way as to generate a circulating power of order 100 W for a sample volume of 10 mm.sup.3. The feedback, provided via a volume Bragg grating, reduces the laser bandwidth to 4 cm.sup.−1. Spectra of spontaneous Raman scattering from ambient atmospheric air, detected collinearly with the pump, were recorded with a limit of detection below 1 part-per-million.

A Raman spectrometer 1 comprising a laser 1001 for illuminating a sample S under investigation, an auto-focusing system for focusing the laser 1001 on the sample S under investigation, and a detector 1010 for detecting Raman spectra emitted in response to illumination by the laser 1001. The auto-focusing system further comprises at least one adjustable focusing element for adjusting the location of the focus of the laser, a determination unit 1012 for determining a selected location for the focus of the laser 1001, and a control unit for adjusting the adjustable focusing element to focus the laser at said selected location determined by the determination unit 1012. The auto-focusing system is arranged under the control of software to enable determination of the selected location for the focus of the laser 1001.

Systems for confocal Raman spectroscopy of points of interest or regions of interest with concurrent imaging are disclosed. The imaging may be used for real time selection of points of interest or regions of interest for Raman spectroscopy and to monitor for unwanted motions of a sample while Raman spectra are acquired. Disclosed embodiments apply Reflectance confocal microscopy (RCM) in a confocal Raman spectroscopy system. A single laser may be used as a light source for both RCM and micro-Raman spectroscopy. A Faraday optical isolator may be applied to extract RCM signals for imaging Systems as described herein have example application for ex vivo sample and in vivo skin measurement.

Arrangements and methods are provided for obtaining information associated with an anatomical sample. For example, at least one first electro-magnetic radiation can be provided to the anatomical sample so as to generate at least one acoustic wave in the anatomical sample. At least one second electro-magnetic radiation can be produced based on the acoustic wave. At least one portion of at least one second electro-magnetic radiation can be provided so as to determine information associated with at least one portion of the anatomical sample. In addition, the information based on data associated with the second electro-magnetic radiation can be analyzed. The first electro-magnetic radiation may include at least one first magnitude and at least one first frequency. The second electro-magnetic radiation can include at least one second magnitude and at least one second frequency. The data may relate to a first difference between the first and second magnitudes and/or a second difference between the first and second frequencies. The second difference may be approximately between −100 GHz and 100 GHz, excluding zero.

A stimulated Raman scattering (SRS) spectrometer for real-time, high-resolution molecular analysis of gases is based on two hollow-core fibres illuminated by a single high-power, short-pulse laser pump. The first fibre is prefilled with high-concentration target gases. Interaction of each target gas inside the first fibre, with the laser pump, generates Raman signals corresponding to the target gases. The combined beam of the Raman signals and the pump laser beam is directed into the second fibre containing the measured target gases. Interaction of each target gas with the combined beam generates the Stimulated Raman Growth (SRG), i.e., amplification of the Raman signal, which is proportional to the corresponding target gas concentration. A receiver subsystem receives the beam from the second fibre, spectrally separates it to wavelengths corresponding to each target gas, extracts the SRG value corresponding to each target gas and calculates the concentration of each target gas.

System for performing chemical spectroscopy on samples from the scale of nanometers to millimeters or more with a multifunctional platform combining analytical and imaging techniques including dual beam photo-thermal spectroscopy with confocal microscopy, Raman spectroscopy, fluorescence detection, various vacuum analytical techniques and/or mass spectrometry. In embodiments described herein, the light beams of a dual-beam system are used for heating and sensing.

A system and method for determining the pH of tissue in vivo. A Raman spectrometer is used to collect Raman spectra from the target tissue. The Raman spectra are baseline subtracted and assessed to determine the concentration of HPO.sub.4.sup.−2 and H.sub.2PO.sub.4.sup.−1 for the purposes of calculating the pH. The approach was validate in vitro using PBS solutions of known pH. The approach was confirmed in vivo using rat and swine models by probing the immediate vicinity of a contusive spinal cord injury (SCI) in the first minutes and hours after injury. Using a dynamic analysis and the Henderson-Hasselbalch equation, the average of (N=12) noninvasive Raman-based pH measurements of CSF was 7.073±0.156 and at >95% confidence there is no statistically significant difference between the Raman-based and the physically sampled results.