The receiver layout from VAHCOLI (IR APD‑based) was adapted for UV operation with PMTs. All beam paths, filters and detectors are mounted on a compact, 3D‑printed support made from carbon‑fiber‑reinforced plastic for high stability and low outgassing. The module contains:
- Beam routing from the scanner to the filter chain
- The full narrowband filter stack (interference filter, solid etalon, confocal etalon)
- Polarization optics for depolarization measurements
- Single‑photon PMTs with combined photon counting and analog readout for wide dynamic range
Laboratory and field tests show no detectable misalignment of the receiver optics over several months. The same material is planned for the housing of the third lidar instrument.
