INK-JET IMAGE FORMING DEVICE

摘要

An ink-jet image forming device such that the test pattern detecting accuracy is improved with a single photodetector. A binarizing circuit (16) which binarizes the output of a sensor for a test pattern includes a peak hold circuit (82) which follows slow change in the sensor output, a voltage dividing circuit (83) which divides the held output, and a comparator (84) which converts the sensor output into a bi-level signal by using the output of the circuit (83) as a threshold. <IMAGE>