Diffraction grating

About: Diffraction grating is a research topic. Over the lifetime, 24884 publications have been published within this topic receiving 372437 citations. The topic is also known as: grating.

Bidirectional bending splitter of designer surface plasmons

Abstract: We propose and experimentally verify a bidirectional bending splitter of designer surface plasmons which is composed of two metallic gratings of trapezoid grooves. A metal wire is used to excite the designer surface plasmons propagating along the gratings. A full-wave numerical method has been used to simulate the performance of the bending splitter. The experimental verifications in the microwave frequencies have excellent agreements to the simulations. It is demonstrated that the splitter can not only split the electromagnetic waves at different frequencies, but also guide the electromagnetic waves effectively for large-angle bending.

Polyfluorene distributed feedback lasers operating in the green-yellow spectral region

Abstract: We report solid-state, optically pumped poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8BT), distributed feedback lasers that operate in the green-yellow spectral region, previously unaddressed with conjugated polymer gain media The lasers were fabricated by spin coating F8BT (the gain medium) onto one-dimensional gratings patterned in silica substrates The emission wavelength could be selected to lie within the range from 558 to 591 nm by controlling the F8BT film thickness and grating periodicity The minimum lasing threshold of 65 nJ per pump pulse (10 ns, 10 Hz, 450 nm) was achieved for a 350 nm spatial period grating with a 180 nm thickness F8BT film The corresponding emission wavelength was 573 nm and the laser slope efficiency was a relatively high 3%

Efficient miniature fiber-optic tunable filter based on intracore Bragg grating and electrically resistive coating

Abstract: An electrically tunable reflection filter based on a platinum-coated single-mode optical fiber that contains an intracore Bragg grating has been demonstrated. The device shows a dc tuning range of 2.15 nm with a corresponding electrical power of 0.54 W. Wavelength modulation (WM) has been observed at frequencies lower than 100 Hz. The wavelength shift depends linearly on the electrical input power. A maximum efficiency of 4.1 nm/W is obtained for dc tuning.

Method and apparatus for coding and reading information in diffraction gratings using the divergence of diffracted light beams

Abstract: An optical memory diffraction grating having a plurality of spaced ridges each having a plurality of optically reflective facets. When illuminated with an incident light beam the grating produces a number of diffracted beams corresponding to the number of facets. The diffracted beams can be machine read by a reading device which produces a reading light beam directed at the grating. The reading device has a plurality of detectors positioned to be illuminated by the diffracted light beams. Information can be stored in the optical memory by locally changing the optical properties of the grating. The grating may be employed in security cards and documents. The grating may be arranged as a bar code or as a pixelgram. Reading, writing and erasing devices are also claimed.

Color filterless display device, optical element, and manufacture

Abstract: A color filterless display device performing color display for expressing one pixel by three RGB sub-pixels includes: a light source; a diffraction grating for separating a light irradiated from this light source into lights of a plurality of wavelength regions; a cylindrical lens array for receiving the separated light and condensing the light while corresponding to each of the sub-pixels; and a liquid crystal cell including a structure portion for correcting an angle of the condensed light for all sub-pixels, wherein, in the structure portion of this liquid crystal cell, a side onto which a light from the cylindrical lens array is made incident is made of a high refractive index layer, an emitting side from which the light is emitted is made of a low refractive index layer, and a Fresnel-type microprism structure is formed by the high refractive index layer and the low refractive index layer.