Material Related Effects on the Structural Thermal Optical Performance of a Thermally Tunable Narrowband Interferometric Spectral Filter

High Spectral Resolution Lidar (HSRL) is a backscatter lidar technique that employs an optical/spectral filter to distinguish between particulate (Mie) and molecular (Rayleigh) backscattered light. By separating the two types of returns, higher accuracy measurements are possible that will enable improved climate models, air quality measurements, and climate forecasting. A spaceborne HSRL instrument can provide great impact in these areas by enabling near-continuous measurements across the Earth, however the optical filter technology has typically been too complex for reliable long-duration space flight due to the need for complicated and costly electro-optic feedback loops, extra alignment detectors, and additional laser sources. Furthermore, these complexities limit the filter from use in other applications. In this research, a high-performance, ultra-narrowband interferometric optical filter with a specific thermo-optical behavior has been designed and built. The interferometer has been designed such that it can be reliably adjusted/tuned by simply monitoring and adjusting the temperature. The greatly reduced operational complexity was made possible through high-accuracy thermal characterization of the interferometer materials, combined with detailed Structural-Thermal-Optical-Performance (STOP) modeling to capture the complicated interactions between the materials. The overall design process, fabrication procedures, and characterization of the optical filter are presented.

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Materials Science and Engineering

Department dc:contributor.department

Materials Science and Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2019

Author dc:creator

• Seaman, Shane Thomas

Chair dc:contributor.committeechair

• Heflin, James R.

Committee members dc:contributor.committeemember

• Pickrell, Gary R.
• Suchicital, Carlos T. A.
• Hostetler, Chris A.

• High Spectral Resolution Lidar
• HSRL
• Wide Angle Michelson Interferometer
• Field Widened
• Aluminum Alloy
• Thermal Repeatability
• Thermal Tuning
• Spectral Filter
• Optical Filter
• Structural Thermal Optical Performance Model
• STOP Analysis
• Poisson Effect

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

vt_gsexam:21141

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/90799