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This study presents a multilayer design and fabrication of an optical notch filter for enhancing visual quality. A cost-effective multilayer design of notch filter with low surface roughness and low residual stress is proposed. A 9-layer notch filter composed of SiO2 and Nb2O5 with a central wavelength of 480 nm is prepared by electron beam evaporation combined with ion-assisted deposition. The optical transmittance, residual stress, and surface morphology are measured by a UV/VIS/NIR spectrophotometer, Twyman-Green interferometer and field emission scanning electron microscopy (FE-SEM). The transmittance of the notch filter at the central wavelength is above 15%, and the average transmittance of the transmission band is about 80%. The residual stress of the notch filter is −0.235 GPa, and the root mean square surface roughness is 1.85 nm. For improving the visual quality, a good image contrast can be obtained by observing the microscopic image using the proposed notch filter.

Owing to increased biosecurity and industrial demands, the poultry houses in Taiwan are generally nonopen and closed types, with automatic environmental control and sensor equipment gradually being installed in such houses. Environmental sensors and poultry health monitoring systems are necessary to improve poultry feeding efficiency and safety. In this work, we developed a goose surface temperature monitoring system based on deep learning using visible image and integrated with infrared thermal image. This system could detect the geese in visible image and obtain the individual goose surface temperature automatically. This system consisted of an embedded system with the trained goose detection model, a visible camera, and an infrared thermal camera. The Mask R-convolutional neural network algorithm was employed to train the goose detection model by the collected goose images. The visible camera captured visible images in the poultry house, in which the geese could be identified by the trained goose detection model. The individual surface temperatures of the geese were obtained through integration of the visible and infrared thermal images. The developed monitoring systems were installed in the land and pool areas of a commercial goose house to monitor the surface temperature of the geese and achieved a precision of 97.1% and recall of 95.1%. In addition, the goose surface temperature of the pool area was observed to be lower than that of the land area. The collected individual goose surface temperature would be used as a management index to poultry house managers.

This paper presents the optimization design of a miniaturized five-element wide-angle fisheye lens using a deep learning algorithm. Zemax optical design software was used to simulate and optimize the wide-angle fisheye lens. A deep learning algorithm helped to find the best combination of different lens materials. We first used six lens elements as an initial configuration to design miniaturized wide-angle fisheye lenses using the optimization process. The optical system components were gradually decreased to five lens elements. Both OKP4HT and polymethyl methacrylate (PMMA) plastic aspheric lenses were selected to replace the second spherical glass lens in the original design. We propose two types of wide-angle fisheye lens designs with four spherical lenses and one aspheric lens. The results for these designs indicated a viewing angle of 174°, a total length of less than 15 mm, a spot size of less than 6 μm, lateral color within ±1 μm, field curvature within ±0.02 mm, and F-θ distortion of ±3.5%. In addition, the MTF value was larger than 0.4 at the spatial frequency of 100 cycles/mm.

Four thermotolerant microalgae were isolated from tropical Taiwan and classified as members of Desmodesmus based on morphological and molecular studies. A platform was established to evaluate their biodiesel production-related traits, including thermotolerance, lipid productivity, lipid oxidative stability and auto-sedimentation. The findings demonstrated thermotolerance of all four species was at the same level, as all could live at 45 °C for 24 h and 50 °C for 8 h with mortality rates below 5% of cells. The lipid productivity of Desmodesmus sp. F2 reached 113 mg/L/d. Its saturated and monounsaturated fatty acids accounted for 75% of the FAMEs, and it required only 3.1 h to achieve 85% sedimentation. Comparing these traits to those of the other three Desmodesmus and microalgae in the literature, Desmodesmus sp. F2 is one of the best candidates for biodiesel production in tropical and subtropical areas. This platform effectively assessed traits of microalgae related to biodiesel production.

A spread spectrum clock generator (SSCG) based on an offset phase-locked loop (OPLL) for the Serial AT Attachment 3 (SATA-III) is presented in this paper. The SSCG can be applied to many systems due to its characteristic of spreading the energy of frequency harmonics and reducing the radiated power per unit bandwidth. In the proposed architecture, a low-frequency spread spectrum signal is synthesized by a direct digital frequency synthesizer (DDFS) and mixed with a high frequency signal to produce a higher modulated reference source. The OPLL is employed to lock its output with the modulated reference to generate the desired spread spectrum clock. This SSCG is fabricated in a 0.13-µm CMOS technology and its area is 0.7 × 0.45 mm2. It reduces main tone power by 16dB while drawing 21.16 mW from a 1.2 V supply.