| 摘要 |
PURPOSE:To improve the accuracy of density measurement regardless of the angle and thickness of a segment by setting an opening part as a window for detecting optical density at an optional angle. CONSTITUTION:Light emitted by an illumination lamp 51 is condensed by a lens 52 to illuminate a measurement position 53 of a chart holding part 8. Reflected light from the measurement position 53 passes through an objective lens 43 and branches in two directions through a prism 54. One light beam is made incident on a photoelectron multiplier tube 58 through a mirror 5, the opening plate 59 of a measurement visual field adjusting mechanism 56, and a color correcting filter 57. The opening part of the opening plate 59 is shaped in such a rectangle that the short sides are 10mum long and the long sides are <=10 times as long as the short sides. Then the direction of the opening part is set to an optional angle in 1 deg. units. The other light beam from the prism 54 enters a magnifying ocular 42 and the image of the measurement position 53 can be observed. Consequently, measurement can be take while the angle is varied variously and the accuracy is improved. |
