| 摘要 |
<p>PURPOSE:To improve a sensitivity and response characteristics by providing the outer surface of a light transmitting medium with a detecting layer containing a detecting material for measuring a change in a light transmitting capability and making the detecting layer contain a non-volatile, water soluble and liquid-like organic compound. CONSTITUTION:A light incident portion 7 and a light receiving portion 8 are provided on one side surface of a light transmitting medium 1 of plate-shaped body with a flat or curved surface and all the other side surfaces are coated by a light reflecting layer 4. Detecting layers 3, 3 containing, for example, a polyhydric alcohol, non-volatile, water soluble and liquid organic compound are formed on the upper and lower surfaces of the medium 1. Light 6 incident from the light incident portion 7 is repeatedly reflected by the reflecting layer 4 and emitted from the light receiving portion 8 to form a long light transmitting path. Further, moisture is applied to the detecting layers 3 for a long period of time in a stable condition. Thus, a sensitivity and a response speed can be improved.</p> |
