US Patent 11686820 Optical sensor with ring-shaped Tx/Rx aperture sharing element (ASE)

Optical sensors and particularly gimbaled optical sensors transmit an active signal at a given wavelength(s) and receive passive signals over a range of wavelengths and the active signal in a common aperture. The sensor includes a Tx/Rx Aperture Sharing Element (ASE) configured with an annular region that couples an active signal having a ring-shaped energy distribution to the telescope for transmission and a center region that couples the passive emissions and the returned active signal to the detector. A beam shaping element such as an Axicon lens, LCWG, Risley Prism, Unstable Optical Resonator or MEMS MMA may be used to form or trace the ring-shaped active signal onto the annular region of the ASE. A focusing optic may be used to reduce the divergence of the active signal so that it is collimated or slightly converging when transmitted such that the returned active signal approximates a spot. A filter wheel may be positioned behind the ASE to present separate passive and active images to the detector. These optical sensors may, for example, be used with guided munitions or autonomous vehicles.