| 摘要 |
<p>Apparatus for altering a light signal comprises first to fourth optical fibers (202-205), each adapted for conducting light to or from the apparatus; first to fourth optical elements (221-224) corresponding, respectively, to the first to fourth optical fibers (202-205); first, to fourth lenses (212-215) corresponding, respectively, to the first to fourth optical fibers (202-205); and a fifth optical element (225). Each lens is positioned with respect to its corresponding optical fiber such that light leaving the optical fiber and striking the lens from a first direction is collimated by the lens and collimated light entering the lens a second direction is focused into the corresponding optical fiber. The first (202) and third (204) optical fibers are positioned such that light entering the first optical fiber (202) traverses the first (221), third (223), and fifth (225) optical elements and is focused into the third optical fiber (204). The second (205) and fourth (203) optical fibers are positioned such that light entering the second optical fiber (205) traverses the second (222), fourth (224), and fifth (225) optical elements and is focused into the fourth optical fiber (203). The fifth optical element (225) is positioned such that a portion of the light leaving the first optical fiber (202) is reflected from the surface of the fifth optical element (225) into the fourth fiber (203) if the surface of the fifth optical element (225) is reflective, this portion depending on the degree of reflectivity of the surface of the fifth optical element (225). At least one surface of one of the optical elements includes a coating that alters the direction or composition of light striking the coating. <IMAGE></p> |
