LIDAR ASSEMBLY WITH STACKED BEAM-STEERING DEVICE

A LiDAR system includes a light detector having a field of view, a beam-steering device (14), and a light emitter (16) aimed at the beam-steering device (14). A beam expander (46) may be between the light emitter (16) and the beam-steering device (14). The beam- steering device is aimed to emit light from the light emitter into a field of illumination (FOI1, FOI2, FOI3, FOI4) overlapping the field of view. Light-emission system includes a diffuser (40) between the beam-steering device (14) and a window (38) to diffuse light emitted from the beam-steering device (14). Beam-steering device (14) includes two beam-steering stages each having a polarization grating. The polarization gratings are designed to diffract light from the light emitter based on the polarization state of the light received by the polarization grating. Beam-steering device (14) includes at least one switchable polarization selector designed to change the polarization state of the light to move the field of illumination relative to the field of view. Preferably, each switchable polarization selector includes a switchable liquid crystal layer operable to be switched between a first state that does not substantially affect the polarization of light traveling therethrough and a second state that alters the polarization of the light traveling therethrough based on voltage applied to the switchable liquid crystal layer. Beam steering is non-mechanical, and more specifically, may be electrically controlled. L'invention concerne un système LiDAR comprenant un détecteur de lumière ayant un champ de vision, un dispositif de direction de faisceau (14) et un émetteur de lumière (16) dirigé vers le dispositif de direction de faisceau (14). Un dilatateur de faisceau (46) peut se trouver entre l'émetteur de lumière (16) et le dispositif de direction de faisceau (14). Le dispositif de direction de faisceau est destiné à émettre de la lumière, provenant de l'émetteur de lumière, dans un champ d'éclairage (FOI1, FOI2, FOI3, FOI4) chevauchant le champ de vision. Le système d'émission de lumière comprend un diffuseur (40) entre le dispositif de direction de faisceau (14) et une fenêtre (38) pour diffuser la lumière émise par le dispositif de direction de faisceau (14). Le dispositif de direction de faisceau (14) comprend deux étages de direction de faisceau ayant chacun un réseau de polarisation. Les réseaux de polarisation sont conçus pour diffracter la lumière provenant de l'émetteur de lumière sur la bas