Abstract
High spatial resolution, low inter-pixel crosstalk, high signal-to-noise ratio (SNR), adequate application dependent speed, economical and energy efficient design are common goals sought after for optical image sensors. In optical microscopy, overcoming the diffraction limit in spatial resolution has been achieved using materials chemistry, optimal wavelengths, precision optics and nanomotion-mechanics for pixel-by-pixel scanning. Imagers based on pixelated imaging devices such as CCD/CMOS sensors avoid pixel-by-pixel scanning as all sensor pixels operate in parallel, but these imagers are fundamentally limited by inter-pixel crosstalk, in particular with interspersed bright and dim light zones. In this paper, we propose an agile pixel imager sensor design platform called Coded Access Optical Sensor (CAOS) that can greatly alleviate the mentioned fundamental limitations, empowering smart optical imaging for particular environments. Specifically, this novel CAOS imager engages an application dependent electronically programmable agile pixel platform using hybrid space-time-frequency coded multiple-access of the sampled optical irradiance map. We demonstrate the foundational working principles of the first experimental electronically programmable CAOS imager using hybrid time-frequency multiple access sampling of a known high contrast laser beam irradiance test map, with the CAOS instrument based on a Texas Instruments (TI) Digital Micromirror Device (DMD). This CAOS instrument provides imaging data that exhibits 77 dB electrical SNR and the measured laser beam image irradiance specifications closely match (i.e., within 0.75% error) the laser manufacturer provided beam image irradiance radius numbers. The proposed CAOS imager can be deployed in many scientific and non-scientific applications where pixel agility via electronic programmability can pull out desired features in an irradiance map subject to the CAOS imaging operation.
Highlights
Imaging of Electromagnetic (EM) radiation is of fundamental importance to medical, manufacturing, astronomy, aerospace, arts, entertainment, forensics, education, research, and defense sectors
Presented is the Coded Access Optical Sensor (CAOS) imager agile pixel platform for optical imager design that engages an electronically programmable Optical Array Device (OAD) to enable agile pixel coded multiple access of an optical irradiance map subjected to the imaging operation
The CAOS imager can electronically adapt to the specific imaging application and its specific needs to sift out desired image information, including under extreme lighting conditions
Summary
Imaging of Electromagnetic (EM) radiation is of fundamental importance to medical, manufacturing, astronomy, aerospace, arts, entertainment, forensics, education, research, and defense sectors. Over the last 65 years, there have been tremendous technological advances in optical image sensor design including optoelectronic photo-detection CCD and CMOS sensor chips and their custom precision interface optics, as well as advances in coding and imaging techniques like Stimulated Emission Depletion (STED) using fluorescence to achieve spatial resolutions beyond the diffraction limit [1]–[11] These and other prior imager designs approached the optical imaging sensor challenge from a mainly fixed space-time-frequency pixel view point that to a large extent have increased system complexity and limitations, when relying on fluorescence materials, wavelength sensitive coherent sources, detectors, and optics, as well as pixel-scale sensitive mechanical alignments and iterative image processing and recovery methods. The proposed CAOS imager uses image optical irradiance agile pixel position coding via time-frequency modulation codes implemented by a programmable Two Dimensional (2-D) Optical Array Device (OAD) interfaced with a single point optical receive antenna called a point Photo-Detector (PD). The paper concludes with a summary of the presented key CAOS imager design and experimental results
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
