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We report the enhancement of carbon nanotube (CNT) field emitters by growing them directly on stripe-patterned alloy substrates. For a gate voltage of 1300 V, CNT field emitters grown on full and stripe-patterned alloy substrates achieved respective emission currents of 0.22 and 2.32 mA, corresponding to tenfold performance enhancement. Performance enhancement is attributed to the reduced screening effect (as a result of the spacing between strips) during field emission and a damage-free patterning process. To verify the ability of the stripe-patterned CNT field emitters to generate X-rays, we designed and assembled an electron gun through brazing. With the open type X-ray system, an X-ray image of human teeth was successfully obtained, verifying the potential of the stipe-patterned CNT emitters in X-ray applications. [ABSTRACT FROM AUTHOR]

This paper presents a 10-m active optical cable (AOC) utilizing a graded-index plastic optical fiber (POF) for HDMI applications, where 4-channel 10-Gb/s/ch transceiver chipsets were implemented in 0.13-μm CMOS process and integrated upon a FR4 PC-board within pluggable connectors. Passive optical alignment comprising optical devices, optical subassembly, and POF was precisely located within the tolerance range of +/−10 μm, leading to successful mass-production. The transmitter (Tx) includes a VCSEL driver exploiting equalization and feedforward pre-emphasis to support 10-Gb/s data modulation. Also, a novel input data detector is proposed to turn on/off VCSEL diodes automatically for longer sustainability and lower power consumption. The receiver (Rx) employs a double-gain feedforward transimpedance amplifier followed by a selectable two-stage equalizer to choose either 6-Gb/s or 10-Gb/s operations, depending upon the specified HDMI applications. Also, a simple dc offset current cancellation and a novel monitor circuit are proposed for stable biasing and to keep tracking the average photocurrent of each photodiode. Measured results of Tx demonstrate 5.6-mA bias currents and 6.0-mAPP modulation currents, consuming 21.25 mA in maximum, whereas Rx provides 56.7-dBΩ transimpedance gain, 6-GHz bandwidth, and −10.4-dBm optical sensitivity for 10−12 BER with 21.2 mA current consumption. The 10-meter POF AOC demonstrates wide and clean eye-diagrams up to 10 Gb/s, successfully showing 8-Mpixel 60-fps video data stream. [ABSTRACT FROM AUTHOR]

This paper presents a linear-mode optical sensor for the feasible applications of unmanned vehicle LiDAR systems, in which a pulsed-erbium fiber laser is exploited as a light source and a 16-channel transimpedance amplifier (TIA) array is utilized in an optical Rx module with low-cost InGaAs PIN photodiodes. In particular, a voltage-mode CMOS feedforward (VCF-TIA) is newly proposed to achieve twice higher transimpedance gain with lower noise and similar bandwidth characteristics than a conventional inverter TIA, thereby enabling longer detection. Test chips of the 16-channel VCF-TIA array realized in a standard 0.18- $\mu \text{m}$ CMOS process demonstrate 76.3-dB $\Omega $ transimpedance gain, 6.3-pA/sqrt(Hz) average noise current spectral density, less than −33-dB crosstalk between channels, and 29.8-mW power dissipation per channel from a single 1.8-V supply. Automatic gain control is also equipped to extend input dynamic range for near-range detection. Hence, the proposed linear-mode optical sensor clearly detects the reflected optical pulses from the target of 5% reflection rate within the range of 0.5–25 m. [ABSTRACT FROM AUTHOR]

A portable system for fluorescence measurement has been developed for cyanobacteria detection. Exploiting commercially available low-cost photodiodes and a single 9 V supply, the system was able to measure two fluorescence emissions simultaneously. Output voltages resulting from the fluorescence intensity were measured by utilizing two quantum dots of QD565 and QD655. These quantum dots were employed into a NanoGene assay for mcyD gene (synthetase of toxic microcystin) detection of Microcystis aeruginosa. We investigated various operational parameters (e.g., distance, angle between laser emission and sample, and so on) for the proposed system. Measurements indicated the highest output voltage signal was obtained at a distance of 0.5 cm with the right angle (90°) between the laser source and a sample vial. Also, the mcyD gene hybridized with QD565 and QD655 was quantitatively detected by the proposed detection system, i.e., the normalized output voltage (QD655/QD565) was linearly proportional to the mcyD gene copy numbers (y = 0.41 log $x +6.6$ , \text{r}^{2} =0.92 ). Finally, the quantitative data were transferred wirelessly to the readout via Bluetooth. [ABSTRACT FROM PUBLISHER]