牛顿环是在极其接近的两个反射面之间,由反复反射的光线互相干涉而引起的。当反射面之间的距离是2m·λ/2时就出现暗条纹;如果反射面之间的距离为(2m+1)·λ/2时则是亮条纹(图1)。由于工业上有可能利用波长顺序进行检测,所以可使用钠灯等接近单一波长特性的光源来检查玻璃、镜头的平面性及曲率。 Newton’s rings are caused by the repeated reflection of light interfering with each other between two closely spaced reflecting surfaces. Dark streaks appear when the distance between the reflecting surfaces is 2 m · λ / 2, and are bright streaks if the distance between reflecting surfaces is (2m + 1) · λ / 2 (Fig. 1). Since it is industrially possible to detect in the order of the wavelengths, the flatness and curvature of the glass, the lens, and the like can be checked using a light source such as a sodium lamp that is close to a single wavelength characteristic.