| 摘要 |
PURPOSE:To obtain a reflection density measuring apparatus with very limited variations in the measuring density as caused by a change in the measuring surface of a sample, if any, by performing a reflection density measurement based on an added value of optical sensor outputs of a plurality of light receivers. CONSTITUTION:Two light receivers 30d and 30b are so arranged that the heights h1 and h2 are higher than the height h and lower than the height h20 as given when outputs I1 and I2 thereof take respective peak values. On the basis of sum It of the outputs I1 and I2 of both the light receives thus arranged or on the basis of a larger output value Ih, a reflection density is measured. Therefore, for example, when the said h varies at each measurement depending on a sample holding accuracy with a sample holding section and dimensional accuracy of the sample itself or when the value h changes with the deflection of the sample itself during a long-time measurement, variation in the I1 and I2 is very limited with such a change in the value h, thereby enabling a very stable reflection density measurement. |
