Method for determining a position of a liquid jet

A method for determining a position of a liquid jet, wherein the position is defined by at least one of the following features:

• (i) a position of a reference point of the liquid jet and
• (ii) a directional vector associated with the liquid jet,
• comprising the steps:
• a. providing a collision object having a measuring point for interacting with the liquid jet,
• b. detecting a state of the liquid jet in a first spatial configuration of the collision object relative to the liquid jet,
• c. performing at least one configuration change by changing from the first spatial configuration to a second spatial configuration of the collision object relative to the liquid jet, wherein said configuration change results in a change of the state of the liquid jet due to a change of an interaction of the measuring point and the liquid jet,
• d. detecting a spatial difference between the first and second configuration for determining the position of the liquid jet;
• and
• wherein
• e. in order to determine the state of the liquid jet, a measurement light of a desired frequency region of the electromagnetic spectrum is coupled into the liquid jet and at least one of the following effects is detected:
• (a) a back scattering of the measurement light or
• (b) a reflection of the measurement light in the liquid jet or
• (c) an extraction of the measurement light from the liquid jet is detected
• and wherein at least two states of the liquid jet are distinguished, including
• an unperturbed state in which the liquid jet has no interaction with the collision object;
• a perturbed state in which the liquid jet collides at least partially with the measuring point of the collision object, so that a deflection, division or interruption of the liquid jet results.