Space-Qualified Hardware for the CALIPSO Lidar Ron Schwiesow Ball Aerospace and Technologies Corp.

CALIPSO is a pathfinder for the GTWS mission Flight-qualified Nd:YAG lasers demonstrated to 2109 pulses Laser beam expanders with anti-feedback provision 1-m beryllium telescope (OCA/Corning) Flight-qualified PMT and APD detectors with associated preamps High-speed digitizer Powerful, flight-qualified computer with fault tolerance (General Dynamics PowerPC™ 603R) Auxiliary instruments for context imaging (Wide-field Camera and Imaging Infrared Radiometer)

The payload includes 3 instruments Star Tracker Assembly X-Band Antenna Telescope Sunshade Wide Field Camera Imaging Infrared Radiometer Integrated Lidar Transmitter

The payload includes 3 instruments Wide Field Camera Platform Electrical Interface Bracket Star Tracker Assembly X-Band Transmitter Payload Controller Laser Electronics Unit Lidar Receiver Electronics Receiver Power Supply

Monolithic optical bench supports the lidar Lidar Instrument Core Active Boresight Mechanism APD PMTs Laser Radiator Optical Bench Laser Optics Modules Telescope Beam Expander Optics ILT (Integrated Lidar Transmitter) ILR (Integrated Lidar Receiver)

Risk-reduction laser proved concept 2109 pulses demonstrated validated contamination-control procedures verified KTP doubler operation established misalignment tolerance showed benefits of derated components

Laser optics modules are tested and delivered Flight Laser #1 in Sealed Canister Flight Laser #2 Prior to Lid Closure

Laser burn-in is part of the qualification process

Beam-expander optics are delivered and tested All-reflective design Mounts to laser optics module Beam expansion 13x f/1.4 primary mirror >0.98 reflectivity at 532 and 1064 nm

Laser vibration test is done with mass model of beam expander

Laser functional test verifies performance 110 mJ each wavelength 20.25-Hz PRF 25-pm linewidth at 532 nm 6-8 mm-mrad beam quality polarization purity 3700:1

All-beryllium telescope has fast primary and f/4.7 secondary

Tested telescope assembly has been delivered from vendor

First fold mirror assembly includes field stop and flexure mounts

Refractive collimator and flexure mounts tested as a subassembly

Dichroics, mirrors, and polarizing beamsplitter tested separately

Sandwich etalon filter for 532 nm provides good optical performance

Sandwich etalon passed thermal and mechanical qualification Housing provides thermal stabilization and uniformity Etalon polished to approximate wavelength, angle-tuned to precise wavelength, thermal tuned to track changes Bandpass 42 pm Peak transmission >0.81 Contrast ratio >160 Birefringence <0.001 crosstalk

Flight APD includes preamp and stabilization circuitry Based on MOLA design QE 0.40 Noise 0.004 pW Hz-½ Bandwidth 4 MHz

Cabling mockup prepares for final integration and test

Structures include optics bench, sunshade, and housing

Composite structure is assembled for testing

The composite structure is qualified with mass models in place Structure includes sunshade Components mounted to outside of payload housing Optical bench floats inside housing

Optical bench is a monolithic composite structure

Optical bench is also tested with mass models of components

Wide-field camera is based on standard CT-633 star tracker Longer lens, narrower FOV than CT-633 Neutral density filter with full aperture Bandpass filter 620 - 670 nm 512x512 CCD as push-broom scanner RS-422 synchronous serial I/O Flight PWAs Flt Lens Assembly

Imaging infrared radiometer is developed by SODERN Based on Boeing microbolometer arrays Mirror for 2-point calibration 6464 snapshot array 3 spectral channels sequential Mirror Mechanism EM Housing Structure Eng Model Flight Infrared Sensor Module (IASI)

Payload Simulator Allows testing of interface to spacecraft platform Currently in service at Alcatel in France

Launch planned for April04 Dual launch with CloudSat on dual launch adapter fitting Delta II 7420 launch vehicle 3-m standard fairing