A vertically supported, two-axial scanning micromirror with an optical reflection area of 600 μm × 600 μm has been successfully demonstrated using a 2 μm thick standard planar polysilicon surface micromachining process. The micromirror was lifted from the substrate and vertically supported by locking springs and hinges using a micromanipulator under a probe station. It was torsionally actuated ...

Vertical cavity surface emitting lasers are semiconductor lasers where the optical cavity is defined epitaxially, perpendicular to the surface of the wafer. This gives rise to optical and electrical properties that are quite different from the traditional edge emitting lasers that are now used in microwave photonic links. This work is an investigation into the suitability of using multimode VCS...

We report a novel individually addressable, individually wavelength tunable 8 x 6 vertical cavity surface-emitting laser (VCSEL) array. A two-dimensional array of individually wavelength-tunable VCSELs is very attractive for free-space optical interconnect in massively parallel computers [ 1-21. VCSEL’s have large mode spacing due to the very short cavity and are particularly suitable for conti...

Surface tension profiles in vertical soap films are experimentally investigated. Measurements are performed by introducing deformable elastic objets in the films. The shape adopted by those objects once set in the film is related to the surface tension value at a given vertical position by numerically solving the adapted elasticity equations. We show that the observed dependency of the surface ...

A textured surface appears slanted about a vertical axis when the image in one eye is horizontally enlarged relative to the image in the other eye. The surface appears slanted in the opposite direction when the same image is vertically enlarged. Two superimposed textured surfaces with different horizontal size disparities appear as two surfaces that differ in slant. Superimposed textured surfac...

Ultrasonic vibration assisted single point incremental forming (UVaSPIF) is based on localized plastic deformation in a sheet metal blank. It consists to deform gradually and locally the sheet metal using vibrating hemispherical-head tool controlled by a CNC milling machine. The ultrasonic excitation of forming tool reduces the vertical component of forming force. In addition, application of ul...

Liquid sloshing is a common phenomenon in the transporting of liquid tanks. Liquid waves lead to fluctuating forces on the tank wall. If these fluctuations are not predicted or controlled, they can lead to large forces and momentum. Baffles can control liquid sloshing fluctuations. One numerical method, widely used to model the liquid sloshing phenomena is Smoothed Particle Hydrodynamics (SPH)....

This thesis describes new laboratory observations concerning the interaction between a series of steep incident waves and vertical, surface piercing, cylinders. The motivation for the study arose as a result of wave impact damage sustained to the undersides of several concrete gravity-based structures in the northern North Sea. Earlier work, Swan et al., (1997), demonstrated that in the case of...

Vertical cavity surface emitting terahertz lasers can be realized in conventional semiconductor microcavities with embedded quantum wells in the strong coupling regime. The cavity is to be pumped optically at half the frequency of the 2p exciton state. Once a threshold population of 2p excitons is achieved, a stimulated terahertz transition populates the lower exciton-polariton branch, and the ...

are maintained. If the etching depth is equal to an integral number of half-wavelengths, uniformly high reflectivity across the active L. Fan, M.C. Wu, H.C. Lee and P. Grodzinski . mesa is achieved. The top electrodes which simultaneously pump the phase-shifted and non-phase-shifted region are then deposited by evaporation and lift-off processes. Fig. 2 shows the scanning electron micrograph (S...