Electromechanically Rotatable Cross-Shaped Mid-IR Metamaterial

We present an electromechanically rotatable infrared (IR) cross-shaped metamaterial (CSM) in the mid-IR wavelength range. The CSM configuration is composed of double gold layers with cross-shaped nanostructures. To investigate the fano-resonance within CSM nanostructures, the aspect ratios and length ratios of CSM are compared and discussed. The electromagnetic responses exhibit the characteristics of large tuning range, tunable broad and narrow bandwidths. By properly tailoring the aspect ratio of CSM, the resonance can be tuned with bidirectional tuning in the range of 650 nm. CSM with different length ratios exhibit narrowband resonances around the wavelength of 4.6 μm and broadband resonances in the wavelength range of 5.0 μm to 6.5 μm. These characteristics of CSM with different aspect ratios and length ratios could be potentially used in IR narrowband and broadband filter. To further increase the flexibility of proposed electromechanically rotatable CSM, an actively tunable narrowband and broadband filter in the mid-IR wavelength range is performed. This study provides a unique approach to realizing an IR filter, with high flexibility.

Camera Unavoidable Scene Watermarks: A Method for Forcibly Conveying Information onto Photographs

When a scene’s image rights need to be protected e.g. a stage performance, it is valuable to use human imperceptible methods to forcibly add markers to a camera’s perception of the scene regardless of the camera’s precise location, focus distance, or shutter speed. This work expands upon extant methods for adding human imperceptible, camera perceptible markers to scenes but does so with the assumption that the photographer will take natural steps to avoid capturing the markers. The proposed method utilizes a combination of a traditional method of adding an image to the scene, and projections from the scene onto the camera’s entrance pupil. This method is intended to function even when the target camera utilizes an IR filter and has a shutter speed 1/60 s. More interestingly, the combination of traditional images with projecting onto the camera allows this method to not be reliant upon knowledge of the camera’s focus settings, or the precise location of the camera. It is, however, marred by numerous other requirements which make the method unreliable.