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We demonstrate experimentally the detection of detailed human cardiac mechanical activity in a remote, non-contacting, and non-ionizing manner using a pulsed laser vibrometer. The highly sensitive pulsed laser vibrometer allows the detection of the temporally-phased mechanical events occurring in individual cardiac cycles even from the surface of clothing-covered extremities of the subjects. Fine structures of the detected cardiac traces are identified with their meanings assigned and corroborated using accelerometer and electrocardiogram measurements obtained concurrently with the pulsed laser vibrometer studies.

We present experimental demonstration utilizing phase-shifting resonant vibrometry to determine the presence and position of embedded defect inside a device under test (DUT) whose awkward surface shape prohibits the use of conventional ultrasonic transducers.

We wrapped 150 nm period aluminum wire grid polarizer (WGP) with AlSiOx by using atomic layer deposition at 250 degrees C. The nanometer precision coating defined the spacer to double the spatial frequency of the 100 mm diameter grating fabricated by using a legacy immersion holography setup at 351 nm wavelength. Half-pitch grating of approximately 38 nm was demonstrated with good pattern uniformity, excellent repeatability, and a wide processing window. We believe 10 nm half-pitch grating over even larger areas are viable, overcoming one major hurdle to commercialize nanoimprint.

Jian (Jim) Wang *, Paul Sciortino, Feng Liu, Ping Yuan, Xuegong Deng, Frank Walters, Xiaoming Liu, Joel Bacon and Lei Chen NanoOpto Corporation, 1600 Cottontail Lane, Somerset, NJ 08873 ABSTRACT Aluminum nanowire-grid polarizers and polarizing beam splitters with a fixed pitch (i.e., period) of ~146 nm but a wide range of linewidths (from 1700 nm). The performance trade-off between transmittance/reflectance and extinction ratio is investigated in details. The developed high-performance large-area broadband nanowire-grid polarizer opens the potential for many optical applications particularly integrated optics. Keywords: polarizer, polarizing beam-splitter, wire-grid, nanoimprint lithography, interference lithography, aluminum RIE, nano-grating 1. INTRODUCTION Polarizers and polarizing beam splitters are essential optical devices for most optical systems and optical networks. It transmits the component of the electric field in the direction of its transmission axis and blocks the orthogonal component. This preferential treatment of the two components of the electric field is achieved by selective absorption (or called dichroism) or selective refraction/reflection. The most common dichroic polarizer is the Polaroid H-sheet, which is made by stretching a heated polyvinyl alcohol sheet while impregnated with iodine atoms. In the near infrared wavelength, a famous dichroic polarizer is Corning’s PolarCor

We demonstrate for the first time a 10 Gb/s EA-modulated wavelength-selectable DBR laser module with an integrated semiconductor optical amplifier. Transmission over 82 km of standard fiber with -3 dBm average power on 20 channels spaced by 50 GHz is achieved.

In order to meet the increasing market needs for uncooled lasers for such applications as fiber- in-the-loop, high efficiency, high power, and highly reliable 1.3 micrometer uncooled InGaAsP/InP strained multi-quantum well Fabry-Perot lasers were fabricated with 50 mm wafer processing. Slope efficiency as high as 0.39 W/A and peak power as high as 46 mW at 85 degrees Celsius was obtained by optimizing the device structure for high temperature operation. We have also demonstrated excellent uniformity and reproducibility over 6 wafers. Reliability was also shown to be very good. More than 10,000 chips sites are available on a 50 mm wafer, and the cost is expected to be low. Because of the high performance, these lasers are expected to be used for various applications.

117 and 150nm pitch polymer gratings were successfully fabricated on plastic substrate over large area by nanoimprint lithography. Nanowire-grid polarizers were made by depositing Al on the sidewalls of the gratings at oblique angles. The effects of grating period, grating linewidth, Al depth, and thickness were studied in detail. Excellent contrast (∼1000:1) and high transmittance (80%–90%) (without antireflection coating) at the wavelength of 500nm and above were demonstrated.

Large-area, 100mm in diameter, aluminum nanowire grids with 40nm line/78nm space were fabricated with full-wafer immersion interference lithography. The aluminum nanowire grids with a 59nm half-pitch work as a highly efficient optical polarizer for deep ultraviolet wavelength down to ∼250nm. In addition, an extremely high contrast from 10 000:1 to 50 000:1 was achieved across the whole visible and near-infrared wavelength range, along with good transmittance (85%–90%). The broadband large-area high-performance polarizer operating down to deep ultraviolet wavelength opens up applications including semiconductor lithography and metrology applications.

Plastic nanowire-grid polarizers based on small period, 58 and 75nm half-pitch, Al gratings are fabricated and studied. Al gratings are made by coating Al on the polymer grating sidewalls at oblique angles. The nanopolymer gratings on plastic film over large area are made by nanoimprint lithography. By optimizing the grating period, grating linewidth, Al coating depth, and thickness, excellent maximum transmittance (Tmax) (80%–90%) and extinction ratio (∼30dB) are achieved.

Both high contrast and high transmittance are preferred for optical polarizers. To achieve high transmittance for aluminum nanowire-grid polarizers, a narrow linewidth is required. In this letter, aluminum nanowire-grid polarizers with 30-nm-wide linewidth and 200nm depth were fabricated by UV-nanoimprint lithography, which leads to ultrahigh transmittance. To achieve a high contrast, the authors fabricated the 30-nm-wide aluminum nanowire structures on both sides of the glass wafers. An extremely high contrast up to 10 000:1 was achieved, in the visible range, along with good transmittance of 83%–87% for the double-side aluminum nanowire-grid polarizers.