Semiconductor laser driver and image forming apparatus incorporating same
AssigneeRicoh Company, Ltd.
InventorTomohiko Kamatani
Life of this patent
Estimating the term…
Abstract
A semiconductor laser driver to execute automatic power control (APC) for multiple semiconductor lasers based on a common APC output from an image controller. The semiconductor laser driver includes a drive circuit to generate an individual APC signal to execute APC for each semiconductor laser based on the common APC signal.
Claims18
A semiconductor laser driver to execute automatic power control (APC) for multiple semiconductor lasers based on a common APC output from an image controller, the semiconductor laser driver comprising:
- a drive circuit to generate an individual APC signal to execute APC for each semiconductor laser based on the common APC signal,
- wherein the semiconductor laser driver comprises multiple drive circuits and each of the multiple drive circuits drives a corresponding semiconductor laser,
- wherein the drive circuit comprises:
- a toggle output terminal through which a toggle signal indicating that the APC has been executed in the drive circuit is output to a next stage of the drive circuit;
- and
- a toggle input terminal through which a toggle signal output from a previous stage of the drive circuit is input to the drive circuit, and
- wherein the drive circuit executes APC based on the individual APC signal after the toggle signal is input to the toggle input terminal and outputs the toggle signal to the next stage of the drive circuit through the toggle output terminal after APC has been executed.
A semiconductor laser driver to execute automatic power control (APC) for multiple semiconductor lasers based on a common APC output from an image controller, the semiconductor laser driver comprising:
- a drive circuit to generate an individual APC signal to execute APC for each semiconductor laser based on the common APC signal,
- wherein the drive circuit further comprises a counter to count the number of common APC signals, wherein the common APC signal is a pulse signal output in a predetermined cycle and the drive circuit counts the number of common APC signals, generates each individual APC signal based on the number of counted common APC signals, and executes APC for the respective semiconductor lasers based on the individual APC signal.
A semiconductor laser driver to execute automatic power control (APC) for multiple semiconductor lasers based on a common APC output from an image controller, the semiconductor laser driver comprising:
- a drive circuit to generate an individual APC signal to execute APC for each semiconductor laser based on the common APC signal,
- wherein, when the semiconductor laser driver executes APC for one of the multiple semiconductor lasers, the drive circuit sets a current flowing to other multiple semiconductor lasers below an oscillation threshold current (including 0 mA).
A semiconductor laser driver to execute automatic power control (APC) for multiple semiconductor lasers based on a common APC output from an image controller, the semiconductor laser driver comprising:
- a drive circuit to generate an individual APC signal to execute APC for each semiconductor laser based on the common APC signal,
- wherein the drive circuit detects a rising edge of the common APC signal output from the image controller and executes APC for the semiconductor lasers within a predetermined time period after detection of the rising edge.
Dependencies are inferred from the claim text.