Heat assisted detection and ranging based on spectropolarimetric imaging

Patent metadata

Field	Value
Publication number	US-2025060251-A1
Application number	US-202418935719-A
Country	US
Kind code	A1
Filing date	Nov 4, 2024
Priority date	Dec 6, 2019
Publication date	Feb 20, 2025
Grant date	—

Abstract

An image processing system includes a processor configured to receive heat radiation from a scene by a spectropolarimetric imaging system adapted to generate a plurality of spectral frames, generate 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, extract scene associated spectral information, 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, generate reference spectral information as a function of temperature and thermal texture, match 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 the associated variation, and extract spectral metadata from the matched reference spectral information for the associated material based on the match.

First claim

1 . An image processing system, comprising:
a processor configured to:
receive heat radiation from a scene by a spectropolarimetric imaging system adapted to generate a plurality of spectral frames associated within the scene;
generate 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, extract 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, generate reference spectral information as a function of temperature and thermal texture;
match 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 the associated variation; and
extract spectral metadata from the matched reference spectral information for the associated material based on the match to thereby generate object surface texture in said thermal infrared images.

1 . The image processing system of claim 1 , 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.

2 . The image processing system of claim 1 , 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

⁢

𝕋

i
⁢
v

⁢

S
v

⁢
Δ
⁢

v

≡

∑
v

𝕄

i
⁢
v

⁢

S
v

,

​

𝕄

i
⁢
v

≡

Z
v

⁢

𝕋

i
⁢
v

⁢
Δ
⁢

v

,

where N i 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 v min and v max for each application of the bandpass filter,
Δv represents width of discretized frequency band,
Z v 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 S v represents the extracted spectral information associated with the scene, where

S
v

=

(

𝕄
iv

)

-
1

⁢

N
i

.

3 . The image processing system of claim 1 , 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

)

⁢

XB
v

0

,

where
⁢

B
v

≡

Assignees

• Purdue Research Foundation

Inventors

• Jacob Zubin
• Bao Fanglin
• Wang Xueji

Classifications

• G01J3/00

  Spectrometry; Spectrophotometry; Monochromators; Measuring colours · CPC title

• G01N21/21

  Polarisation-affecting properties (G01N21/19 takes precedence) · CPC title

• G01J3/108

  for measurement in the infrared range · CPC title

• G06T2207/10036

  Multispectral image; Hyperspectral image · CPC title

• G06T2207/10048

  Infrared image · CPC title