| 摘要 |
PROBLEM TO BE SOLVED: To improve fluorescent light collection efficiency and sensitivity while suppressing an increase in the size of an objective lens.SOLUTION: An objective lens 17 is configured so as to have a convex lens portion 26 in the central portion and a truncated conical cylindrical body 27 on the periphery of the convex lens portion 26. Therefore, of the fluorescent light emitted from a sample 16, the fluorescent light b having a large radiation angle that is not incident on the convex lens portion 26 can be completely reflected by the outer peripheral surface 27b of the cylindrical body 27 and collected, thereby enabling light having a large radiation angle, which cannot be collected by a conventional convex lens, to be collected. As a result, a highly sensitive fluorescent light information reading device can be realized in which fluorescent light collection efficiency can be improved while suppressing an increase in the size of the objective lens, and in which S/N deterioration caused by the presence of undetected fluorescent light blocked by a prism 20 can be prevented. |
