| 摘要 |
<p>An apparatus for determining optical density of a liquid sample and an optical waveguide thereof are provided, wherein the optical waveguide comprises: an input end (20) for receiving a divergent beam; an output end (30) for outputting an illuminating beam; a longitudinal cavity (40) extending from the input end (20) till the output end (30); a first pinhole (50) located at a first predetermined distance from the input end (20) within the said longitudinal cavity (40) for receiving the divergent beam and for generating a fringe pattern (90), said first pinhole (50) bifurcating the longitudinal cavity (40) into a first and a second light propagating regions (70,80), the longitudinal cavity (40) forming the first light propagating region (70) being provided with a reflective coating (R) on its internal surface to enable internal reflection of the divergent beam; and a second pinhole (60) located at the output end (30) for receiving the fringe pattern (90) thus generated by the first pinhole (50) and for outputting the illuminating beam corresponding to a central bright fringe (100) contained in the said fringe pattern (90) via the output end (30).</p> |
