Multigrid interference structures with variable selective characteristics

The results of investigations of quasi-optical interference structures based on crossed grid-polarizers are presented. It is shown that such structures have the possibility of smoothly varying their spectral and polarization characteristics: width and form of transmission or reflection bands, polarization ellipse parameters that are their principal advantages in comparison with alternative structures. One variant of a 3-grid structure has been made and tested for application as a tunable 75 GHz region band-pass filter in experiments at the ELMI-device (BINP).