| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical member that prevents an excitation light beam from returning to a light source to destabilize light emission by the light source, utilizing an apparatus that performs measurement utilizing surface plasmon resonance.SOLUTION: The shape of a prism is set, such that an excitation light beam that enters the prism to cause surface plasmon resonance to be generated is not irradiated to the corners of the prism, after it undergoes total reflection inside the prism. The angle of a surface that the excitation light exits the prism is set to an angle, at which the excitation light beam is not totally reflected. As a result, the excitation light beam is prevented from returning to a light source and from being scattered inside the prism, and thereby, the accuracy of measurements can be improved. |
