| 摘要 |
PROBLEM TO BE SOLVED: To provide a density measuring instrument which prevents the occurrence of measurement errors by a fluctuation in the light source characteristics of measuring light during density measurement and is high in accuracy, is compact and is low in both of a cost and a running cost and an image recorder utilizing the same. SOLUTION: This instrument has light emitting elements for emitting light of three colors varying in wavelength regions from each other, a drive means for causing the light emitting elements to emit light, a light quantity measuring means for measuring the light reflected by an object to be measured by erradiating the object with the light emitting elements or the quantity of the light transmitted through the object to be measured and a light emission control means for controlling the drive means so as to measure the light quantity by the light quantity measuring means after causing at least one of the light emitting elements to emit light for a prescribed period of time. |
