| 摘要 |
Even when the distance from an objective lens to a sample differs, the distribution of light from the sample can be detected accurately. A first lens 23 for converting light from the objective lens into parallel light is composed of a concave lens part 32 having a concave curved face 32c in a center portion of a flat face 32a, and a convex lens part 33 having a convex curved face 33c around a flat face 33b. Further, the first lens 23 includes first and second regions for diverging light through the flat face 33b and the concave curved face 32c and a third region for collecting light through the convex curved face 33c and the concave curved face 32c. When the sample is placed on a sample table while being sealed in a two-dimensional electrophoresis substrate, light totally reflected by a side surface of the objective lens is caused to enter the second region. In contrast, when the sample is directly placed on the sample table, the light is caused to enter the third region. As a result, in any of the cases, the rays of light d emitted from the first lens 23 are nearly parallel to one another, and are nearly parallel to the optical axis. |
