Heat assisted detection and ranging based on spectropolarimetric imaging

A method of generating object surface texture in thermal infrared images comprising:

• receiving heat radiation from a scene by a spectropolarimetric imaging system adapted to generate a plurality of spectral frames associated within the scene;
• generating the plurality of spectral frames associated with the scene, each frame having a plurality of pixels;
• for each pixel from the generated plurality of spectral frames, extracting spectral information associated with the scene, including pixel-specific temperature representing an object's temperature, and thermal texture factor representing the object's texture;
• for each of a plurality of materials having a specific emissivity in a library, generating reference spectral information as a function of temperature and thermal texture;
• matching the extracted spectral information for each pixel from the generated plurality of spectral frames to the generated reference spectral information using a statistical method to minimize an associated variation;
• extracting spectral metadata from the matched reference spectral information for the associated material based on the match;
• wherein the plurality of spectral frames from the spectropolarimetric imaging system are each generated by applying a plurality of associated bandpass filters to the spectropolarimetric imaging system and passing the heat radiation therethrough;
• and
• wherein the extracted spectral information associated with the scene from the spectropolarimetric imaging system for each pixel from the generated plurality of spectral frames is based on
• N
• i
• =
• ∑
• v
• =
• v
• min
• v
• max
• Z
• v
• i
• ⁢
• v
• S
• v
• ⁢
• Δ
• ⁢
• v
• ≡
• ∑
• v
• i
• ⁢
• v
• S
• v
• ,
• i
• ⁢
• v
• ≡
• Z
• v
• i
• ⁢
• v
• Δ
• ⁢
• v
• ,
• where Ni represents output of the spectropolarimetric imaging system for each application of the associated bandpass filter i,
• v represents frequency,
• iv represents transmittance curve of each pixel of the plurality of spectral frames for discretized frequency bands between vmin and vmax for each application of the bandpass filter,
• Δv represents width of discretized frequency band,
• Zv represents response curve of each pixel of the plurality of the spectral frames,
• iv is a transformation matrix for each application of the bandpass filter, and
• where Sv represents the extracted spectral information associated with the scene, where
• Sv=(iv)−1Ni.

A method of generating object surface texture in thermal infrared images comprising:

• receiving heat radiation from a scene by a spectropolarimetric imaging system adapted to generate a plurality of spectral frames associated within the scene;
• generating the plurality of spectral frames associated with the scene, each frame having a plurality of pixels;
• for each pixel from the generated plurality of spectral frames, extracting spectral information associated with the scene, including pixel-specific temperature representing an object's temperature, and thermal texture factor representing the object's texture;
• for each of a plurality of materials having a specific emissivity in a library, generating reference spectral information as a function of temperature and thermal texture;
• matching the extracted spectral information for each pixel from the generated plurality of spectral frames to the generated reference spectral information using a statistical method to minimize an associated variation;
• extracting spectral metadata from the matched reference spectral information for the associated material based on the match;
• wherein the plurality of spectral frames from the spectropolarimetric imaging system are each generated by applying a plurality of associated bandpass filters to the spectropolarimetric imaging system and passing the heat radiation therethrough;
• and
• wherein the generated reference spectral information from the spectropolarimetric imaging system as a function of temperature and material texture for each material in the library is obtained from:
• S
• v
• ⁢
• m
• =
• ε
• v
• ⁢
• m
• ⁢
• B
• v
• +
• (
• 1
• -
• ε
• v
• ⁢
• m
• )
• ⁢
• X
• ⁢
• B
• v
• 0
• ,
• where
• B
• v
• ≡
• B
• v
• (
• v
• ,
• T
• )
• =
• 2
• ⁢
• h
• ⁢
• v
• 3
• c
• 2
• ⁢
• 1
• e
• h
• ⁢
• ν
• κ
• B
• T
• -
• 1
• ,
• B
• v
• 0
• ≡
• B
• v
• (
• v
• ,
• T
• 0
• )
• ,
• where, κB is the Boltzmann constant,
• v represents frequency,
• h is the Planck constant,
• c is the speed of light,
• m represents a material chosen from the library,
• T represents the temperature of the target,
• T0 represents the ambient temperature,
• εvm represents the emissivity of the chosen material, and
• X represents thermal texture factor.