Micro-retroreflector array fabricated by the LIGA process

We report on the fabrication of a one-dimensional micro-retroreflector array with a pitch of 100 micrometers. The array was fabricated by X-ray lithography and the LIGA process in a 1 mm thick PMMA layer and subsequently covered with Au. The area of the array is 1 mm x 10 mm. The high precision of the LIGA-based fabrication process allows one to use the element in spectrometers. Here, it is suggested to use it for the implementation of a transversal filter for femto-second pulses.