| 摘要 |
<p>PROBLEM TO BE SOLVED: To make precise measurement perform by always keeping constant the distance between one side of a dielectric block and a metal film in an Otto type surface plasmon sensor. SOLUTION: This surface plasmon sensor comprises a dielectric block 10, a metal film 12 disposed at a distance from one side 10a of the dielectric block 10 in such a way to face it, an optical system 15 whereby a light beam 13 from a light source 14 is made to enter the side 10a of the dielectric block 10 at various incident angles including a total internal reflection angle, and, in the total internal reflection of the light beam 13 off the side 10a of the dielectric block 10, a means 16 for detecting an incident angle at which the luminous energy decreases by the resolution of the total internal reflection. This surface plasmon sensor is provided with a light source 21 for distance measurement whereby a light beam 20 for distance measurement of a wavelength the metal film 12 absorbs is totally reflected on the side 10a of the dielectric block 10, a move means 22 for making the dielectric block 10 and the metal film 12 a relative move in the direction of their clearance change, a light detection means 24 for detecting the luminous energy of the light beam 20 totally reflected on the side 10a of the dielectric block 10, and a control means 26 for controlling drive of the move means 22 so that the luminous energy detected is kept constant.</p> |
