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Chronic wound biofilm infections represent a major clinical challenge which results in a substantial burden to patients and healthcare systems. Treatment with topical antibiotics is oftentimes ineffective as a result of antibiotic‐resistant microorganisms and biofilm‐specific antibiotic tolerance. Use of biocides such as hypochlorous acid (HOCl) has gained increasing attention due to the lack of known resistance mechanisms. An HOCl‐generating electrochemical bandage (e‐bandage) is designed that delivers HOCl continuously at low concentrations targeting infected wound beds in a similar manner to adhesive antimicrobial wound dressings. A battery‐operated wearable potentiostat is developed that controls the e‐bandage electrodes at potentials suitable for HOCl generation. It is demonstrated that e‐bandage treatment is tunable by changing the applied potential. HOCl generation on electrode surfaces is verified using microelectrodes. The developed e‐bandage shows time‐dependent responses against in vitro Acinetobacter baumannii and Staphylococcus aureus biofilms, reducing viable cells to nondetectable levels within 6 and 12 h of treatment, respectively. The developed e‐bandage should be further evaluated as an alternative to topical antibiotics to treat wound biofilm infections. [ABSTRACT FROM AUTHOR]

A photodiode (PD)-type CMOS active pixel sensor (APS) pixel is comprised of a reverse-biased p-n-junction diode (PD) for photon conversion and charge storage, and a number of MOS transistors. Junction capacitance of the PD has two major components; bottom plate (area) and side wall (periphery). Both play important roles in the electro-optical performance of PD-APS pixels. This paper reports PD peripheral junction utilization effects on the pixel's electro-optical performance, full-well capacity and spectral response for an 18 [micro]m x 18 [micro]m CMOS PD-APS pixel were improved by opening multiple circular holes in the PD diffusion layer. A prototype CMOS APS imager was designed, fabricated, and tested in 0.5-[micro]m, 5 V, 2P3M CMOS process, containing a 424 x 424 pixel array with smaller sub-arrays for multiple pixel designs. Four test pixels with 7, 11, 14, and 17 circular, 1.6-[micro]m-diameter holes were placed on one pixel array, with one control pixel for reference. Pixel characteristics, dark current, PD capacitance, quantum efficiency, sensitivity, and pixel full-well capacity were measured. It was found that increased PD junction peripheral would potentially help to improve total capacitance of the PD, with the expense of higher dark current. We also found that increased PD peripheral capacitance improves spectral response up to 12% of the PD-APS pixel, especially at short wavelengths. Index Terms--CMOS image sensors, image sensors, sensitivity.

Many algorithms have been developed for complementary metal–oxide–semiconductor (CMOS) image sensors to speed up analogue‐to‐digital (A‐to‐D) conversion of captured images. However, there is no objective blind‐image quality metric available to compare and quantify the quality and effectiveness of these speed‐up algorithms. In this work, we developed a blind‐image quality and complexity metric for this purpose. The proposed metric relies on counting the successive zeros in a code histogram. The proposed metric is called the conversion complexity metric (CCM). The CCM is designed to quantify how complex, and to predict how much time and power consuming a captured image is for A‐to‐D conversion, mainly by integrating (ramp) type A‐to‐D converter used in column‐parallel architectures of a CMOS image sensor (CIS). The proposed metric, CCM, is tested for linearity, monotonicity, and sensitivity to many types of introduced distortion. The CCM is compared with other no‐reference and full‐reference image quality and complexity metrics. It accomplished, for brightness change distortion, 99% linearity and 316% sensitivity, providing a computationally efficient blind‐image quality metric that no other metrics provide for CIS to intelligently adjust and optimise on‐chip analogue and digital signal processing. [ABSTRACT FROM AUTHOR]

A trapezoid (TZOID) pixel array complementary metal oxide semiconductor (CMOS) image sensor, and a pixel-resolution mapping (P-RM) method to extract information from the observed objects without requiring any specific patterns or man-made markings, are proposed for traffic applications. The size of each pixel in the TZOID imager was determined by pixel design equations based on the relationship between the pixel's physical size and related spatial resolution. The TZOID imager trades detection accuracy for a tolerable data loss to reduce communication bandwidth and computation power. The P-RM method determines the pixels' actual resolutions in the real world of the captured imaged by both standard rectangular single- and multiresolution TZOID pixel arrays. Both indoor and outdoor experiments were performed using single- and multiresolution imagers. The TZOID imager integrated circuit (IC) was fabricated in a 0.18-μm CMOS process. It was tested, and its performance parameters were compared with an off-the-shelf CMOS image sensor IC. Tests showed that the TZOID generates 98% less data than that of a standard image sensor, trading off only 2% detection accuracy. Results also show that the proposed method provides a general procedure for designing a multiresolution sensor for traffic applications. [ABSTRACT FROM AUTHOR]