| 摘要 |
PURPOSE:To obtain an adequate density and contrast by storing the density of an original and the characteristic of a light source for illuminating the original into an ROM, etc. and controlling the density and contrast in accordance with the stored density and characteristic. CONSTITUTION:The output from a means 1 for detecting the density of an original is digitized by an A/D converter 2 and is then fed via an input-output port 3 to a CPU4. The CPU4 selects an emission quantity from the table for the density-emission quantity characteristic stored in an ROM5 according to the integrated value of the density data and feeds the same to the port 3. The data on the emission quantity is analogized with a D/A converter 6 and is thereafter used to control the emission quantity of a light source 12. The relation between the density and the emission quantity is preferably so controlled that a copy having the same density is obtd. from an original having an intermediate density, the emission is increased for the original having a slightly higher density and the density of the copy is made approximate to the density of the original for the original having an extremely high (or low) density. |
