Adjustment of dot size for laser imagers

摘要

Fine pulse width modulation (PWM) adjustments in the output of a laser printer (11) are accomplished by receiving values from a bit map (21-24) and modifying the values in accordance with values in a lookup table (LUT 27). The lookup table (27) is subdivided into a plurality of blocks, and a selection of the blocks is made in accordance with external values (45, 47, 51-54). This allows the output of a pulse width modulation circuit (29) to be adjusted to a precision that is greater than that afforded by the bit size of the values from the bit map (21-24). The use of plural blocks in the lookup table (27) permits adjustments in the output of the pulse width modulation circuit (29) in accordance with external factors such as relative humidity (45), sensitivity of an optical photoreceptor (48), and developer life (51-54). <IMAGE>