Comparison of the Inversion Periods for Mid-wave IR (MidIR) and Long-wave IR (LWIR) Polarimetric and Conventional Thermal Imagery

We report the results of a diurnal study that recorded radiometrically calibrated polarimetric and conventional thermal imagery in the mid-wave IR (MidIR) and long-wave IR (LWIR) to identify and compare the respective time periods in which minimum target contrast is achieved. The MidIR polarimetric...

Full description

Saved in:
Bibliographic Details
Main Authors: Felton, M, Gurton, K P, Pezzaniti, J L, Chenault, D B, Roth, L E
Format: Report
Language:English
Subjects:
BOLOMETERS
Electrical and Electronic Equipment
Electricity and Magnetism
FAR INFRARED RADIATION
FOCAL PLANE ARRAYS
IMAGE PROCESSING
INDIUM ANTIMONIDES
Infrared Detection and Detectors
INTERMEDIATE INFRARED RADIATION
INVERSION
IR(INFRARED)
LWIR(LONG WAVE INFRARED)
MICROBOLOMETERS
MIDIR(MID WAVE INFRARED)
Optics
POLARIMETERS
Test Facilities, Equipment and Methods
THERMAL IMAGERY
THERMODYNAMICS
Online Access:Request full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We report the results of a diurnal study that recorded radiometrically calibrated polarimetric and conventional thermal imagery in the mid-wave IR (MidIR) and long-wave IR (LWIR) to identify and compare the respective time periods in which minimum target contrast is achieved. The MidIR polarimetric sensor is based on a division-of-aperture approach and has a 640 512 indium antimonide (InSb) focal-plane array (FPA), while the LWIR polarimetric sensor uses a spinning achromatic retarder to perform polarimetric filtering and has a 324 x 256 microbolometer FPA. The images used in this study include the S0 and S1 Stokes images of a scene containing a military vehicle and the natural background. Relevant meteorological parameters measured during the test period include air temperature, ambient loading in the LWIR, relative humidity, cloud cover, height, and density. The data show that the chief factors affecting polarimetric contrast in both wavebands are the amount of thermal emission from the objects in the scene and the abundance of MidIR and LWIR sources in the optical background. In particular, we observed that the MidIR polarimetric contrast was positively correlated to the presence of MidIR sources in the optical background, while the LWIR polarimetric contrast was negatively correlated to the presence of LWIR sources in the optical background. Performed in collaboration with Polaris Sensor Technologies, Inc., Huntsville, AL; and U.S. Army Armament Research and Development Engineering Center, Picatinny Arsenal, NJ. The original document contains color images.