JPS647771A - Photolithographic equipment - Google Patents

Abstract

PURPOSE:To rationalize and simplify the operation by correlating the basic density value of a sample dot on a continuous gradation image with the numerical value of the network area percent at a sample dot on a network point gradation image corresponding to said sample dot. CONSTITUTION:A detection part 1 detects transmitting light or reflecting light from the respective parts of an original 5, and converts it to a voltage signal. A color decomposing apart 2 converts respective voltage signals of R, G, B, USM from the part 1 to decomposed color signals of Y, N, C, K. A gradation adjustment part 3 so processed the signals Y, M, C, K that the density value at an arbitrary sample dot of the original 5, the density value difference at the brightest dot on the image 5, and the numerical value of the network dot area percent of the sample dot on a print image corresponding to the sample dot of the original 5 correlate with each other, and outputs the result to an output part 4. The part 4, based on an output signal from the part 3, exposes a film with a laser beam. In such a way, the process can be rationalized and simplified under any condition.