| 摘要 |
PROBLEM TO BE SOLVED: To provide a light quantity measuring device and a color image forming device capable of maintaining highly precise full color picture quality with satisfactory reproducibility. SOLUTION: An optical measuring device is constituted of an LED for irradiating a density patch with lights, a lens 14 for converging the lights reflected from the density patch, and a photodiode 16 for receiving lights from the lens 14. The lens 14 is positioned at a case body 17, and the influence of aberration generated in the peripheral edge area of the lens 14 is removed, and a ring- shaped lens aperture 13 for deciding the valid diameter of the lens is arranged near the lens 14. A circular light absorbing member 11 is fit into the inside face of the lens aperture 13, and the light absorbing member 11 is constituted of a circular resin ring 19 on whose inside face a light absorbing sheet 15 made of black light absorbing materials is formed, and the lights reaching from the lens 14 to the inside face of the lens aperture 13 are absorbed by the light absorbing sheet 15. |
