A laser scanning unit for an image forming device includes a light source for emitting a laser beam, a scanning member having at least one reflective surface for scanning the laser beam onto an imaging surface across a plurality of scan lines, and driver circuitry for driving the light source to emit the laser beam. The driver circuitry has a first input for receiving a first signal indicating image information and a second input for receiving a second signal indicating shading information. The driver circuitry modulates the laser beam based on the first signal to form an image on the imaging surface corresponding to the image information and adjusts an output power of the modulated laser beam based on the second signal to substantially reduce energy variation across each scan line.

A laser scanning unit for an image forming device includes a light source for emitting a laser beam, a scanning member having at least one reflective surface for scanning the laser beam onto an imaging surface across a plurality of scan lines, and driver circuitry for driving the light source to emit the laser beam. The driver circuitry has a first input for receiving a first signal indicating image information and a second input for receiving a second signal indicating shading information. The driver circuitry modulates the laser beam based on the first signal to form an image on the imaging surface corresponding to the image information and adjusts an output power of the modulated laser beam based on the second signal to substantially reduce energy variation across each scan line.

In image-checking equipment, a detector reads a line-shaped check image formed on a sheet and acquires image data on the check image. A controller calculates an edge blur in a rising edge and a falling edge of the image data, calculates a line width of the check image. The controller refers to a correction table with the measured values of the edge blur and the line width of the check image, and acquires a corrected line width value based on the correction table to obtain the real line width of the check image.

A setting unit of a controller mounted on a control board sets a first mode for generating, from image data, PWM data indicating a pattern for causing an LD to emit light and transmitting to a laser driving board, or a second mode for transmitting to the laser driving board image data prior to generation of the PWM data. A data conversion unit, in the first mode, converts inputted image data into N pieces of PWM data respectively corresponding to N LDs, and in the second mode, converts inputted image data into image data for each scanning line. A P/S conversion unit converts data outputted from the data conversion unit from a serial format into a parallel format, and transmits the converted data to the laser driving board as control data.

An adjustment includes a first current adjustment for adjusting a first current Idrv by supplying a superimposed current of the first current Idrv and a second current Ib to an LD 101a, and a second current adjustment for adjusting the second current Ib by supplying the second current Ib to the LD 101a without supplying the first current Idrv thereto. Upon reception of an image forming instruction, a control unit performs adjustment in order of the second current adjustment for the first time, the first current adjustment for the first time, the second current adjustment for the second time, and the first current adjustment for the second time. An execution period of the second current adjustment for the first time is longer than an execution period of the second current adjustment for the second time.

An image forming apparatus comprising: an exposing unit including: a first light source comprising a first light emitter and a first light receiver including a first electric output responsive to a received light quantity of the first light emitter; a second light source comprising a second light emitter and a second light receiver including a second electric output responsive to a received light quantity of the second light emitter; and a first light-source driver electrically connected to the first light source and the second light source. The first light-source driver includes: a first output terminal electrically connected to the first light emitter; a second output terminal electrically connected to the second light emitter; and an input terminal electrically connected to both the first electric output and the second electric output.

Provided is an image forming apparatus outputs for each pixel, together with the pixel data, pixel position data which adjusts an irradiation position for each pixel of the laser light in a range of one pixel in a scanning direction, generates a pulse width signal at a pixel position corresponding to the pixel position data and having a pulse width corresponding to the pixel data, generates the laser light based on the pulse width signal, and corrects, via the adjustment by the pixel position data, the pulse widths of the pulse width signals to different values depending on whether the pulse width signals of the adjacent two pixels contact with each other.