Abstract: A hypodermic needle device (10) includes a hypodermic needle (1) having a tubular bore and at least one optical waveguide (12, 15) extending along said needle so that a distal end of the at least one optical waveguide is in proximity to a tip of the needle. A first coupler (25) secures the optical waveguide within the needle at the proximal end of the needle, and a second coupler (27) removably secures a proximal end of the optical waveguide to a respective illumination source (14) in order that light will emanate from the distal end of the at least one optical waveguide. The second coupler (27) contains a lens for focusing light from the illumination source through the at least one optical waveguide (12, 15), and the second coupler (27) is remote from the first coupler (25).

Abstract: An optical perturbation sensing system includes a probing beam incident on a medium with perturbations and a sensing beam redirected from the medium and incident on a surface area of a photodetector. A reference beam directed onto the photodetector surface forms, with the sensing beam, an interference pattern on the photodetector surface and a phase patterner with at least two phase regions across its section, generates different phases in different regions of the interference pattern. An array of photodetector elements detects each phase region of the interference pattern and a constructive combiner subtract pairs of the detected signals, squares the subtracted signal squares, and sums the squared signals to form a stronger detected signal with reduced intensity noise, reduced background noise, and reduced sensitivity to phase drifts.

Abstract: There is provided an optical perturbation sensing system, including a probing beam incident on a medium, a sensing beam redirected from the medium and incident on a surface area of a photodetector, an array of photodetector elements, and a constructive combiner for constructively combining detected signals from the elements, to form a stronger detected signal. A method for detection of perturbations in a medium is also provided. The invention avoids the need for detection of the phase or the frequency variations of the scattered signal as used in the more complex hitherto-proposed approaches.

Abstract: An optical perturbation sensing system includes a probing beam incident on a medium with perturbations and a sensing beam redirected from the medium and incident on a surface area of a photodetector. A reference beam directed onto the photodetector surface forms, with the sensing beam, an interference pattern on the photodetector surface and a phase patterner with at least two phase regions across its section, generates different phases in different regions of the interference pattern. An array of photodetector elements detects each phase region of the interference pattern and a constructive combiner subtract pairs of the detected signals, squares the subtracted signal squares, and sums the squared signals to form a stronger detected signal with reduced intensity noise, reduced background noise, and reduced sensitivity to phase drifts.

Abstract: There is provided an optical perturbation sensing system, including a probing beam incident on a medium, a sensing beam redirected from the medium and incident on a surface area of a photodetector, an array of photodetector elements, and a constructive combiner for constructively combining detected signals from the elements, to form a stronger detected signal. A method for detection of perturbations in a medium is also provided. The invention avoids the need for detection of the phase or the frequency variations of the scattered signal as used in the more complex hitherto-proposed approaches.