Abstract: A needle for invasive medical use includes a long extended cylindrical needle shaft having an axis and an outer surface area, with a short shaft end at a first end of the shaft with a beveled tip with a pointed end, and a needle hub attached to a second end of the shaft including a device to indicate the location of the shaft end during use inside a body. The needle has a flexible joint with a notch within the shaft at the beginning of the shaft end. The device is a displacement sensor for detecting a displacement of the shaft end relative to the rest of the shaft resulted from a force applied to the shaft end when the needle hub is moved and a signal conductor to transmit the detected signals. The invention further describes a needle assembly comprising such a needle and a syringe attached to said needle hub, whereas an evaluation unit is connected to the signal conductor.

Abstract: A needle for invasive medical use includes a long extended cylindrical needle shaft having an axis and an outer surface area, with a short shaft end at a first end of the shaft with a beveled tip with a pointed end, and a needle hub attached to a second end of the shaft including a device to indicate the location of the shaft end during use inside a body. The needle has a flexible joint with a notch within the shaft at the beginning of the shaft end. The device is a displacement sensor for detecting a displacement of the shaft end relative to the rest of the shaft resulted from a force applied to the shaft end when the needle hub is moved and a signal conductor to transmit the detected signals. The invention further describes a needle assembly comprising such a needle and a syringe attached to said needle hub, whereas an evaluation unit is connected to the signal conductor.

Abstract: An optical measuring element measures forces in at least one direction. The measuring element has a single-piece structure. There is an outside wall with notches introduced therein. Each notch defines parallel edges, and the notches define more or less elastically flexible zones in the structure and constitute the only connection between a first region and a second region of the structure. For optical distance measurements between the two regions of the structure, one or more optical fibers are each attached with one end thereof to a region of the structure such that reflective surfaces are located close to the ends. The reflective surfaces are firmly connected to another region. The optical fibers are disposed on the outside wall.

Abstract: An optical force sensing element for microsurgical instruments and methods measures force F in three orthogonal directions and includes a monolithic cylinder structure, a cylindrical surface and a top surface that absorbs and transmits the force F. Three punch-like notches, all being parallel to the y-direction, are spaced apart along the z-axis and form two blades between the first and second notch and between the second and the third notch. Three channels parallel to the z-axis extend from the bottom surface to the top surface and cross the first notch while bypassing the other two notches. Three optical fibres, each fixed in one of the three channels, all entering the structure from the bottom surface, cross the first notch and end at or near the top surface while being interrupted in the first notch and forming two surfaces of each fibre that define a Fabry-Perot interferometric cavity.