Patent ID: 7839427

Claim:
A multi-beam image forming apparatus in which a semiconductor laser array including plural semiconductor laser elements serves as an optical beam generation unit, the apparatus comprising: a printing ratio counting unit that counts printing ratios of the semiconductor laser elements in plural printing areas divided in a scanning direction based on image data transmitted from a host unit; and a light amount control unit that controls emission light amounts of the semiconductor laser elements based on a result from the printing ratio counting unit, wherein the light amount control unit calculates droop correction values corresponding to the printing areas from the printing ratios of the semiconductor laser elements based on the printing ratios in the printing areas counted by the printing ratio counting unit so as to correct the emission light amounts of the semiconductor laser elements, and wherein the light amount control unit has an optical correction table including correction values corresponding to the printing ratios of the semiconductor laser elements and correction coefficients of the printing areas and has a light amount setting unit, and the light amount setting unit calculates the droop correction values of the semiconductor laser elements corresponding to the printing areas based on information of the optical correction table.