PBJacquemin .com.Luggage Scanning with Coherent Beam Interference for Contraband Detection. Coherent X-Ray Beam Interference
Systems Engineer
Peter B. Jacquemin
Email Peter B. Jacquemin

Project and Research Descriptions
Luggage Scanning Device using Coherent X-Ray Beam Interference

Project and Research Descriptions: | Applied Optics | Microscope | Telescope | Scanning Mechanisms | Target Acquisition |
| Acoustics | Luggage Scanning | Feedback Controls | Image Processing | 3D Virtualization | Holographic Microscope |

Luggage Scanning Device using Coherent X-Ray Beam Interference

I have developed a luggage scanning device to detect concealed objects using coherent beam interference and vibrational spectroscopy that excites the harmonic frequencies of the object within the luggage walls which are lower than the carrier frequency of the interfering beams.

  • Crossing beam interference excites lower resonant mode vibrations of the luggage contents as the high frequency carrier wave passes through the luggage walls unimpeded
  • Luggage contents are detected by forward and backward scattering sensors with vibrational spectroscopy providing identification of the contents by comparing the signature of dangerous polymer materials to acceptable objects of a similar chemical composition

Coherent waves from two sources are converged to interact with one another. The high frequency carrier wave passes through the air and the luggage virtually unimpeded, but where they cross one another the wave energy can either reinforce or cancel. This interaction can produce a sub-harmonic which can excite the resonant modes of the contents.

The crossing beam geometry produces a fringe pattern of interference based on the common carrier frequencies of the two beams. A signal frequency can be added to excite the particular resonant frequencies of certain material and polymer compounds. The forward and back scattering sensors measure the vibration response and the spectrum is compared to the signature of desired materials to screen.

The optical equivalent uses a Fresnel biprism to converge the two beams. The fringe spacing (fs) is a function of the wavelength and the beam convergence angle. The fringe spacing produces the sub-harmonic that excites the resonant frequencies of the contents as the walls remain un-reactive to the carrier frequency.