| 摘要 |
<p>A light modulator includes elongated elements (24A) arranged parallel to each other and supported on posts (26A, 28A). In a first mode, the modulator diffracts light into at least two diffraction orders. In a second mode, the modulator diffracts light into a single order. Each of the elongated elements comprises a blaze profile, which preferably comprises a reflective stepped profile (32A, 34A) across a width of each elongated elements, or which comprises a single surface inclined at the blaze angle. Each elongated element comprises a first conductive element. In the first diffractive mode, a first electrical bias is applied between the first conductive elements and the substrate (22A). In the second diffractive mode, a second electrical bias is applied to adjust the relative heights of the blazed portions. An alternative embodiment employs multiple elongated elements arranged in groupings of at least three elongated elements. When the elongated elements are at a first height, light reflects from the elongated elements. Individual electrical biases are applied between the first conductive elements and the substrate to adjust the relative heights of the multiple elongated elements and to cause light to diffract into a single order.</p> |
