We present a general approach for optimizing the diffraction efficiency of a phase-type spatial light modulator (SLM). While the SLM displays a one-dimensional phase grating, the phase shift of one pixel in the grating is varied and the first-order diffraction efficiency is measured. This is repeated pixel-by-pixel to find the optimum phase encoding for the device that maximizes the diffraction...

Biological systems have been an infinite reservoir of inspiration ever since humans started to develop tools and machinery. Just as early scientists and engineers attempted to mimic birds and fish in the development of flying machines and submarines, today, new technologies find their inspiration from biology, such as gecko feet (1), antireflective eye lenses (2), iridescent insects (3), and wa...

─We present the design and simulation results of an integrated wavelength demultiplexer. The device’s major components, which include the Silicon-on-insulator (SOI) etched diffraction grating and waveguide integrated InP/InGaAs MSM photodetectors are discussed in detail. The Silicon-on-insulator diffraction grating is fabricated using standard CMOS processes. The photodetectors are integrated o...

An approach that uses an electro-optically tunable two dimensional phase grating to enhance the resolution in digital holographic microscopy is proposed. We show that, by means of a flexible hexagonal phase grating, it is possible to increase the numerical aperture of the imaging system, thus improving the spatial resolution of the images in two dimensions. The augment of the numerical aperture...

The performance of the recently developed EUV phase-shifting point diffraction interferometer (PS/PDI) depends heavily on the characteristics of the grating beamsplitter used in the implementation. Ideally, such a grating should provide throughput of better than 25% and diffraction efficiency, defined as the ratio of the first-diffracted-order power to the zero-order power, variable in the rang...

Holographic gratings are recorded in colloidal suspensions of silver nanoparticles by utilizing interfering nanosecond pulses. The diffraction efficiency is measured with continuous-wave light. An instantaneous response together with a transient grating are observed: the nanoparticles absorb the pump light and heat up. Heat is transferred to the solvent, and a delayed thermal grating appears. T...

Fringe formation in the two-grating interferometer is analyzed in the presence of a small parallelism error between the diffraction gratings assumed in the direction of grating shear. Our analysis shows that with partially coherent illumination, fringe contrast in the interference plane is reduced in the presence of nonzero grating tilt with the effect proportional to the grating tilt angle and...

We demonstrate a simple yet high performance phase grating with switchable diffraction angles using a fringe field switching (FFS) liquid crystal (LC) cell. The LC rubbing angle is parallel to the FFS electrodes (i.e. α = 0°), leading to symmetric LC director distribution in a voltage-on state. Such a grating exhibits three unique features: 1) Two grating periods can be formed by controlling th...

The resolution, bandwidth, and duty cycle of a laser beam scanner make it useful as an image recorder. Laser image recorders can have either a flatfield or a cylindrical recording surface, the flatfield being preferable in applications where dimensional stability is extremely important . A problem with flat field recording systems is the difficulty in obtaining a constant scan rate. This diffic...

The diffraction by a finite sinusoidal grating is analyzed for the H-polarized plane wave incidence using the Wiener-Hopf technique combined with the perturbation method. Assuming the depth of the grating to be small compared with the wavelength and approximating the boundary condition on the grating surface, the problem is reduced to the diffraction problem involving a flat strip with a certai...