Temperature resistant anti-reflective coating on Si-wafer for long-wave infra-red imaging.

A micromachined Silicon lid, sealed by CuSn solid liquid interdiffusion bonding is a promising approach for hermetic sealing of microbolometers for use in low-cost thermal cameras. However, since ∼30% of long-wave infrared light is reflected at an uncoated single Si-air interface, anti-reflective treatments are required. Traditional anti-reflective coatings are inapplicable since CuSn solid liquid interdiffusion bonding requires heating to about 270 °C and these multi-layer coatings fail due to differing coefficients of thermal expansion for the different layers and the substrate.

CardioNet: Automatic Semantic Segmentation to Calculate the Cardiothoracic Ratio for Cardiomegaly and Other Chest Diseases.

Semantic segmentation for diagnosing chest-related diseases like cardiomegaly, emphysema, pleural effusions, and pneumothorax is a critical yet understudied tool for identifying the chest anatomy. A dangerous disease among these is cardiomegaly, in which sudden death is a high risk. An expert medical practitioner can diagnose cardiomegaly early using a chest radiograph (CXR).

To assess the feasibility and diagnostic accuracy of preoperative ultrasound and ultrasound-guided fine needle aspiration cytology of axillary lymph nodes in patients of breast carcinoma.

Background: Metastasis of the lymph node is one of the most significant prognostic factors for breast cancer (BC).

Aim: To predict positivity of the lymph node in BC patients with help of USG and USG-guided FNAC and thus to prevent unnecessary morbidity.

Methods: 50 patients of incisional/true cut biopsy-proven BC patients were included.

Improved wide-field emmetropic human eye model based on ocular wavefront measurements and geometry-independent gradient index lens.

There is a need to better understand the peripheral optics of the human eye and their correction. Current eye models have some limitations to accurately predict the wavefront errors for the emmetropic eye over a wide field. The aim here was to develop an anatomically correct optical model of the human eye that closely reproduces the wavefront of an average Caucasian-only emmetropic eye across a wide visual field.

Influence of base-region thickness on the performance of Pnp transistor-VCSEL.

We have recently reported a 980nm GaAs-based three terminal Pnp transistor-vertical-cavity surface-emitting laser (TVCSEL) operating at room temperature with optical power up to 1.8mW. However, the current gain β = ΔIc/ΔIb was near zero just before lasing and became negative after the lasing threshold.

Speckle reduction using a motionless diffractive optical element.

Speckle reduction by moving diffuser has been previously studied in display systems with coherent light sources, such as lasers. In this Letter, we propose a motionless diffractive optical element (DOE) for speckle reduction. The DOE was designed based on finite-element method simulations, fabricated using micromachining technology, and characterized for despeckle efficiency.

Laser speckle reduction due to spatial and angular diversity introduced by fast scanning micromirror.

We utilize spatial and angular diversity to achieve speckle reduction in laser illumination. Both free-space and imaging geometry configurations are considered. A fast two-dimensional scanning micromirror is employed to steer the laser beam.

Simulation and control of narcissus phenomenon using nonsequential ray tracing. II. Line-scan camera in 7-11 microm waveband.

A nonsequential ray tracing technique is used to calculate the narcissus signature in infrared (IR) imaging cameras having cooled detectors operating in the 7-11 microm waveband. Imaging cameras based on a one-dimensional linear detector array with a scan mirror are simulated. Circularly symmetric diffractive phase surfaces commonly used in modern IR cameras are modeled including multiple diffraction orders in the narcissus retroreflection path to correctly estimate the stray light return signal.

Simulation and control of narcissus phenomenon using nonsequential ray tracing. I. Staring camera in 3-5 microm waveband.

A nonsequential ray tracing technique is used to simulate the narcissus phenomenon in infrared (IR) imaging cameras having cooled detectors. Imaging cameras based on two-dimensional focal plane array detectors are simulated. In a companion article, line-scan imaging cameras based on one-dimensional linear detector arrays are simulated.

Speckle reduction in line-scan laser projectors using binary phase codes.

A Barker binary phase code of maximum length 13 has previously been used for speckle reduction in line-scan laser projectors, and a speckle contrast factor decrease down to 13% has been achieved. In this Letter, Barker-like binary phase codes of lengths longer than 13 are used at an intermediate image plane. It is shown by theoretical calculation that a much better speckle reduction with a speckle contrast factor up to 6% can be achieved by using longer binary phase codes other than the Barker code.