Electro optical Spectrum Flashcards
Define EO
Science and technology of generation, modulation, detection and measurement or display of optical radiation by electrical means
IR BAND: NIR
Solar reflections, very hot objects
0.72-3 microns
IR BAND: Mid IR
Man made emissions, solar reflections
3-6 microns
IR BAND: Far IR
Natural background peak emissions, man made emissions
6-15 microns
Infrared radiation characteristics
All objects above absolute zero emit IR radiation
Absolute 0= 0K = -273C
What three things can happen to energy
Absorption
Reflection
Transmission
Characteristics of lasers
Monochromatic
Highly coherent in Phase
Sharply focused beam
Highly directional
Discuss some applications of EO sensors
EO/IR imaging Systems Video trackers Detectors Terminal homing seekers Automatic target recognizes IRCM Systems Laser Systems Space imaging systems
Types of terminal homing seekers
Imaging - high res and detailed tgt shape
Nonimaging - los res and detail
Types of thermal detectors
Thermal
Quantum - requires cooling
Infrared detection considerations: Source Heating
Sun angle Season Weather Orientation Thermal crossover
Infrared detection considerations: Source viewing
Background
Approach axis
IR Decoys
Distance
Define black body
Hypothetical entity that absorbs all energy
Define emissivity
Ratio of radiant exitance of a given object and a theoretical black body at the same temp
Define radiant exitance
The rate at which radiation is emitted from a unit area
Define reflected IR
Reflected solar radiations
Define thermal radiations
Heat emitted by an object
Is Temperature or Emissitivity more important for Thermal signature
Temperature
Types of EO/IR Imaging Systems
FLIR systems (Far IR) Targeting Pods (Mid/Far IR) Imagery Systems (Visual/Near IR)
Types of Video Trackers
TV Cameras
Targeting Pods
Air-to-Ground Munitions
Types of IR Detectors
IRSTS Systems
Missile Warning Sets
Laser Warning Sets
Types of Laser Systems
Laser Rangefinders
Laser Tgt Designators
What causes atmospheric attenuation
conditions that partially absorb or totally block IR Energy, Such as: moisture dust smoke clouds chemical compounds
What is a detection problem
Detection systems must gather the signal-of-interest and convert to a usable form (resolution)
What are characterstics of Vis and UV Band
Visable passes largely unattenuated through the atmosphere.
UV is attenuated by the atmosphere.
