US 12,228,505 B2
Optical scanning
Thomas A. Puppe, Munich (DE); Nico Vieweg, Stockdorf (DE); and Christian Rausch, Unterhaching (DE)
Assigned to TOPTICA Photonics AG, Gräfelfing (DE)
Filed by TOPTICA Photonics AG, Gräfelfing (DE)
Filed on Jun. 9, 2021, as Appl. No. 17/342,632.
Claims priority of application No. 10 2020 115 338.4 (DE), filed on Jun. 9, 2020.
Prior Publication US 2021/0381964 A1, Dec. 9, 2021
Int. Cl. G01N 21/3581 (2014.01)
CPC G01N 21/3581 (2013.01) [G01N 2201/061 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A device for generating temporally spaced light pulses, comprising
a first light source arranged to emit a first train of light pulses,
a second light source arranged to emit a second train of light pulses, and
a phase-locked loop arranged to regulate the relative phase of the light-pulse trains towards a target value,
wherein each of the two light-pulse trains pass through an optical fiber transmission path of at least one meter length to an application site that is spatially remote from the light sources at the end of the optical fiber transmission paths, wherein a detection apparatus comprising at least one sensor and arranged to interact with the phase-locked loop is provided which detects a phase difference in the light-pulse trains at the application site caused by propagation-time differences along the optical fiber transmission paths, wherein the phase-locked loop is configured to incorporate the phase difference detected at the application site in the regulation of the relative phase of the light pulse trains emitted by the first and second light sources, wherein the phase-locked loop is configured to incorporate the phase difference detected at the application site in the regulation of the relative phase of the light pulse trains emitted by the first and second light sources, such that a phase difference caused by external fluctuations acting on the optical fiber transmission paths is compensated for.