The hologram (16) is preferably a computer generated thin hologram (16) which does not rely on Bragg diffraction.
Typically, at least 50 percent of the particles will form a hexagonal array, capable of exhibiting Bragg diffraction.
The output optical signal (6) is formed as the result of interference of the light reflected due to the Bragg diffraction from the parts of the diffraction grating recorded in different layers.
An image is then recorded of x-ray radiation diffracted by a section of the object, including at least one line of Bragg diffraction by the object.
The photonic band gap optical fiber propagates an optical beam of a predetermined working wavelength in a photonic band gap formed by the Bragg diffraction grating.
The front surface distributed Bragg grating is closer to the output aperture than the rear surface distributed Bragg grating.
There is a space (15) between the rear surface distributed Bragg grating and the front surface distributed Bragg grating.
The grating device comprises at least one Bragg grating.
Each SBG device has a diffracting state and a non diffracting state.
Each SBG device is characterised in that it provides a grating in a separate switchable region and is clear elsewhere.
The at least one fibre optical waveguide (5, 5', 5") comprises at least one fibre Bragg grating (6, 6', 6").
The sensors (14) include fibre bragg gratings (41, 43) for detecting differential pressure across diaphragms (42) and for detecting temperature.
The cladding has two variation regions located on opposite sides of the Bragg grating to allow attachment mechanisms to be disposed against the optical fiber.
Techniques for using a nonlinearly-chirped fiber Bragg (101, 102, 103, and 104) grating to produce tunable dispersion-slope compensation.
A rear surface distributed Bragg grating (12) with a tuning current electrode (19) is formed on a surface of said laser heterostructure.
The laser also includes a front surface distributed Bragg grating (14) with a tuning current electrode (16) on a surface of the laser heterostructure.
The coating layers (306) have thickness that gradually increase in a direction moving away from an X-ray generation source to satisfy the following Bragg's Diffraction Equation: 2d sinθ=n
In one embodiment of the invention the display and forms a virtual image of an image of information encoded in the SBG device.