Abstract: Imaging systems and methods for simultaneous real and Fourier plane imaging. In one example, an imaging system includes at least one optical element configured to receive and focus incident electromagnetic radiation from a viewed scene, a first detector positioned at an image plane of the at least one optical element and configured to produce a first image of the viewed scene, and a second detector positioned at a Fourier plane of the at least one optical element and configured to produce a second image of the viewed scene, the first and second detectors configured to receive the electromagnetic radiation and produce the first and second images, respectively. The system may additionally include an optical component, such as a beamsplitter, for example, configured to divide and direct the incident electromagnetic radiation to the first and second detectors.

Abstract: A non-retro-reflective imaging system and methods in which tilted image plane imaging is combined with selective Fourier filtering to substantially eliminate retro-reflection from the system. In certain examples, tilted image plane imaging is achieved using sliced source imaging. Through rotation of the image plane, the majority of incident light is reflected off-axis, rather than being retro-reflected. The Fourier filter is used to block incoming light from a particular angle that would otherwise be normally incident on the rotated image plane and retro-reflected. One example of a non-retro-reflective imaging system includes an optical element that focuses electromagnetic radiation onto a tilted image plane, an imaging sensor co-aligned with the tilted image plane, and a Fourier filter positioned in a Fourier plane of the optical element, a position of the Fourier filter in the Fourier plane determined by the tilt angle of the tilted image plane.

Abstract: Imaging systems and methods for simultaneous real and Fourier plane imaging. In one example, an imaging system includes at least one optical element configured to receive and focus incident electromagnetic radiation from a viewed scene, a first detector positioned at an image plane of the at least one optical element and configured to produce a first image of the viewed scene, and a second detector positioned at a Fourier plane of the at least one optical element and configured to produce a second image of the viewed scene, the first and second detectors configured to receive the electromagnetic radiation and produce the first and second images, respectively. The system may additionally include an optical component, such as a beamsplitter, for example, configured to divide and direct the incident electromagnetic radiation to the first and second detectors.

Abstract: Methods and apparatus for covert detection of an interrogating device. In one example a method includes receiving an interrogation beam at an optical system, imaging a scene including a source of the interrogation beam without retro-reflecting the interrogation beam to produce an image, and analyzing the image to determine an approximate location of the source within the scene. In some examples, a threat detection sensor is used to further analyze the interrogation beam to determine information about the interrogating device.

Abstract: A non-retro-reflective imaging system and methods in which tilted image plane imaging is combined with selective Fourier filtering to substantially eliminate retro-reflection from the system. In certain examples, tilted image plane imaging is achieved using sliced source imaging. Through rotation of the image plane, the majority of incident light is reflected off-axis, rather than being retro-reflected. The Fourier filter is used to block incoming light from a particular angle that would otherwise be normally incident on the rotated image plane and retro-reflected. One example of a non-retro-reflective imaging system includes an optical element that focuses electromagnetic radiation onto a tilted image plane, an imaging sensor co-aligned with the tilted image plane, and a Fourier filter positioned in a Fourier plane of the optical element, a position of the Fourier filter in the Fourier plane determined by the tilt angle of the tilted image plane.

Abstract: Methods and apparatus for covert detection of an interrogating device. In one example a method includes receiving an interrogation beam at an optical system, imaging a scene including a source of the interrogation beam without retro-reflecting the interrogation beam to produce an image, and analyzing the image to determine an approximate location of the source within the scene. In some examples, a threat detection sensor is used to further analyze the interrogation beam to determine information about the interrogating device.