摘要 |
An optical measuring system determines coordinates of points for distance measurement. The measuring system includes a radiation source for emitting electromagnetic radiation and a receiving unit having a filter unit for extracting electromagnetic radiation in a defined wavelength range and having, a detector, such that the radiation extracted by the filter unit is detectable by the detector. The filter unit includes at least two mirror elements which are at least partly reflective and constructed in a multilayered fashion. The mirror elements are substantially parallel to one another. Two adjacent mirror elements in each case enclose a cavity and are arranged at a specific distance from one another. An optical thickness is defined by a refractive index of the cavity and by the distance between the mirror elements. Optical thickness varying means operate to varying the optical thickness, such that an extractable wavelength range of the filter unit is varied. |