| 摘要 |
The invention provides an optical device, including a light-transmissive substrate, and a pair of different, parallel gratings including a first grating and second grating, located on the substrate at a constant distance from each other, each of the pair of parallel gratings including at least one sequence of a plurality of parallel lines, wherein the spacings between the lines gradually increase from one edge of the grating up to a maximum distance between the lines, and wherein the arrangement of lines in the second grating is in the same direction as that of the first grating. A system utilizing a plurality of such optical devices is also disclosed. |
| 主权项 |
1. An optical device for the transmission of optical signals of different wavelengths from a single source to a plurality of receiving channels, comprising:
at least two major surfaces, a first surface and a second surface delimiting a medium wherein the medium between the surfaces is composed of light-transparent material having a constant refractive index; a first grating (G1) and a second different grating (G2), stationary with respect to each other, each having an X-axis and a Y-axis, located on at least one of the major surfaces, at a constant distance from each other, wherein the two gratings are invariant in the Y-axis and solely dependent on the X-axis, each of the gratings, having a lateral dimension, with at least one sequence of a plurality of parallel lines, wherein the spacing between the lines of the first grating (G1) gradually increases in a direction away from an edge of the grating up to a maximum distance, and wherein the spacing between the parallel lines of the second grating (G2) increases in the same direction as the spacing of the first grating; a light source emitting light waves in a given spectral range, at least a first light wave (101) having a first wavelength and a second light wave (102) having a second wavelength, different from the wavelength of the first light wave (101) emanating from the light source, impinging on the first grating (G1) as plane waves in the same direction, the first and second light waves (101, 102) diffracted by the first grating (G1), and subsequently diffracted as output plane waves by the second grating (G2), the first and second light waves (101, 102) impinging on the first grating at different portions along the X-axis being diffracted by the first grating (G1) in different directions toward the second grating, and traverse the second grating (G2), the diffracted first light wave (101) and second light wave (102) being diffracted respectively by the second grating in a first output direction and a second output direction, wherein the first and second output directions are different and directed to two receiving channels (35). |
