| 摘要 |
PURPOSE:To measure diffuse reflection brightness easily and accurately by irradiating a surface to be measured with light uniformly, arranging a black board which removes a regularly reflected component in such a direction that the regularly reflected component is supplied to a brightness measuring instrument, and removing the regularly reflected component. CONSTITUTION:The surface 1 to be measured is irradiated uniformly with light in every direction and the brightness is measured by the brightness measuring instrument 2. The normal 4 to the point where the optical axis crosses the object surface 1 is found to obtain the angle alpha between the measuring instrument 2 and normal 4, the black board 3 is arranged at the position of an angle thetaon the symmetric side of the normal 4, and let angle alpha=theta. Thus, the black board 3 is arranged for the measured value of the brightness measuring instrument 2 to remove the regularly reflected component, measuring the diffuse reflection brightness. Therefore, a diffuse reflected component is measured easily and accurately because the black board for removing the regularly reflected component is arranged. |
