| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a method and an apparatus in which various characteristics such as the reflectivity the like of every light reflecting layer can be measured optically and independently of each other by a method wherein, among from beams of light reflected from a plurality of light reflecting layers, only the beams of light from one reflecting layer as an object to be measured are guided to a corresponding light intensity detector and the oval rate of polarized light is found on the basis of the relationship between the angle of rotation of an analyzer and a detected light intensity. SOLUTION: A laser beam as circularly polarized light is separated axially so as to be incident on a condensing lens 39. An optical recording medium 30 having a plurality of light reflecting layers is arranged near the focus of the condensing lens 39. Beams of light reflected by the plurality of light reflecting layers are made incident again on the condensing lens 39, and they are reflected so as to be transmitted through an analyzer which can be turned around the optical axis. After that, among from the beams of light reflected from the plurality of light reflecting layers, only the beams of light from one light reflecting layer as an object to be measured are guided to a corresponding light intensity detector 10. The oval rate of the circularly polarized light is found on the basis of the relationship between the angle of rotation of the analyzer and a detected light intensity. The magnitude of a refractive index up to the light reflecting layer as the object, to be measured, from the surface of the optical recording medium 30 is measured.</p> |
