TERAHERTZ IMAGING DEVICES AND SYSTEMS, AND RELATED METHODS, FOR DETECTION OF MATERIALS

• US 20140231648A1
• Filed: 02/20/2013
• Published: 08/21/2014
• Est. Priority Date: 02/20/2013
• Status: Active Grant

• Current Assignee: Battelle Energy Alliance LLC (Battelle Memorial Institute)
• Original Assignee: Battelle Energy Alliance LLC (Battelle Memorial Institute)
• Inventors: KOTTER, DALE K.
• Granted Patent: US 9,494,464 B2
• Time in Patent Office: Days
• US Class Current: 250/339.02
• CPC Class Codes: G01J 3/42 Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry beam switching arrangements G01J3/08
• CPC Class Codes: G01J 5/023 Particular leg structure or construction or shape; Nanotubes
• CPC Class Codes: G01J 5/0837 Microantennas, e.g. bow-tie
• CPC Class Codes: G01N 21/3581 using far infrared light; using Terahertz radiation
• CPC Class Codes: G01V 8/005 operating with millimetre waves, e.g. measuring the black losey radiation
• CPC Class Codes: H01Q 21/062 using dipole aerials; H01Q21/067, H01Q21/068 take precedence
• CPC Class Codes: H01Q 9/27 Spiral antennas

Abstract

Terahertz imaging devices may comprise a focal plane array including a substrate and a plurality of resonance elements. The plurality of resonance elements may comprise a conductive material coupled to the substrate. Each resonance element of the plurality of resonance elements may be configured to resonate and produce an output signal responsive to incident radiation having a frequency between about a 0.1 THz and 4 THz range. A method of detecting a hazardous material may comprise receiving incident radiation by a focal plane array having a plurality of discrete pixels including a resonance element configured to absorb the incident radiation at a resonant frequency in the THz, generating an output signal from each of the discrete pixels, and determining a presence of a hazardous material by interpreting spectral information from the output signal.

Claims

1. A terahertz imaging device, comprising:

a focal plane array including;

a substrate; and

a plurality of resonance elements comprising a conductive material coupled to the substrate, wherein each resonance element of the plurality of resonance elements is configured to resonate and produce an output signal responsive to incident radiation having a frequency between about a 0.1 THz and 4 THz range.

2. The terahertz imaging device of claim 1, further comprising a spectral selective filter positioned in a path of the incident radiation prior to the focal plane array, wherein the spectral selective filter includes a plurality of resonance elements tuned to exhibit a resonant frequency for a narrow band THz frequency.

3. The terahertz imaging device of claim 2, further comprising a terahertz radiation source configured to illuminate and object of interest to induce an emission from the object of interest that is received by the focal plane array as the incident radiation.

4. The terahertz imaging device of claim 3, wherein a frequency for a signal generated by the terahertz radiation source and the resonant frequency of the plurality of resonance elements of the spectral selective filter are approximately the same.

5. The terahertz imaging device of claim 3, wherein a frequency for a signal generated by the terahertz radiation source and the resonant frequency of the plurality of resonance elements of the spectral selective filter are matched.

6. The terahertz imaging device of claim 3, wherein the terahertz radiation source and the focal plane array are arranged relative to the object of interest to operate the terahertz imaging device in a back scatter mode.

7. The terahertz imaging device of claim 3, wherein the terahertz radiation source and the focal plane array are arranged relative to the object of interest to operate the terahertz imaging device in a reflection mode.

8. The terahertz imaging device of claim 2, wherein the focal plane array is tuned for a broader band than the spectral selective filter.

9. The terahertz imaging device of claim 8, wherein the spectral selective filter is tuned for a narrow band selectivity for absorption lines of a pre-determined chemical specie.

10. The terahertz imaging device of claim 1, wherein the plurality of resonance elements are arranged in a plurality of sub-arrays, wherein each sub-array includes resonance elements that are tuned to a different frequency within the 0.1 THz and 4 THz range.

11. The terahertz imaging device of claim 10, wherein the different frequencies include frequencies that correspond to different spectral absorption peaks for different materials of interest.

12. The terahertz imaging device of claim 10, wherein the different frequencies include frequencies that correspond to different spectral absorption peaks for a material of interest that has a plurality of spectral absorption peaks.

13. The terahertz imaging device of claim 1, further comprising a portal including a plurality of discrete sensors, wherein each discrete sensor of the plurality of discrete sensors includes the focal plane array.

14. A terahertz imaging system, comprising:

a focal plane array having a plurality of pixels, each pixel having a resonance element configured to absorb incident radiation, resonate at a frequency in the THz range, and responsively generate an output; and

a data acquisition system configured to interpret the output to provide at least one of image data and spectral data.

15. The terahertz imaging system of claim 14, wherein the resonance element has a shape selected from the group consisting of a simple dipole, a bowtie dipole, a spiral, a square loop, a square spiral, a circular loop, concentric loops, an ellipse, a rectangle, a triangle, and a cross.

16. The terahertz imaging system of claim 14, wherein the resonance element includes an electrically conductive material that is selected from the group consisting of manganese (Mn), gold (Au), silver (Ag), chromium (Cr), copper (Cu), aluminum (Al), platinum (Pt), nickel (Ni), iron (Fe), lead (Pb), and tin (Sn), titanium (Ti), and nickel (Ni).

17. The terahertz imaging system of claim 14, further comprising a spectral selective filter having a plurality of resonance elements configured to pass a narrow band of the incident radiation to the focal plane array.

18. The terahertz imaging system of claim 17, wherein the spectral selective filter is configured as a gangbuster filter.

19. A method of detecting at least one hazardous material, the method comprising:

receiving incident radiation by a focal plane array having a plurality of discrete pixels including a resonance element configured to absorb the incident radiation at a resonant frequency in the THz;

generating an output signal from each of the discrete pixels; and

determining a presence of at least one hazardous material by interpreting spectral information from the output signal.

20. The method of claim 19, further comprising receiving the incident radiation by a spectral selective filter prior to receiving the incident radiation by the focal plane array.

21. The method of claim 19, wherein receiving incident radiation by a focal plane array includes passively receiving the incident radiation that was emitted from an object of interest.

22. The method of claim 19, wherein receiving incident radiation by a focal plane array includes actively receiving the incident radiation that was emitted from an object of interest in response to illuminating the object of interest with a terahertz radiation source.