Adjusting electrostatic charges used in a laser printer

A system, comprising:

• a photoconductor drum;
• a corona;
• a printhead;
• a sensing probe;
• an applicator having an applicator voltage, wherein the applicator applies toner to an exposed image area of the photoconductor drum;
• a toner sensing probe;
• and
• a machine control to cause operations, the operations comprising:
• causing the corona to apply a charge on the a surface of the photoconductor drum to create a defined dark voltage;
• causing the printhead to expose an image area of the photoconductor drum using a defined energy level to discharge the charge from the image area to create an exposure voltage;
• measuring, with the sensing probe, the exposure voltage of the photoconductor drum after the image area has been exposed by the printhead;
• performing a first optimization to determine an adjusted dark voltage and an adjusted energy level based on the measured exposure voltage and the defined dark voltage and the defined energy level applied to the photoconductor drum, wherein performing the first optimization comprises performing a non-linear analysis to select the adjusted energy level and the adjusted dark voltage such that the measured exposure voltage of the photoconductor drum is approximately linear with respect to the adjusted energy level;
• receiving, from the toner sensing probe, a toner density of the toner applied to the photoconductor drum;
• and
• performing a second optimization to adjust the applicator voltage to produce a target toner density.

An article of manufacture implemented in a printing system to cause operations with respect to a photoconductor drum, a printhead, and an applicator in the printing system, the operations comprising:

• applying a charge to a surface of the photoconductor drum to create a defined dark voltage;
• exposing an image area of the photoconductor drum with the printhead using a defined energy level to discharge the charge from the image area to create an exposure voltage;
• measuring the exposure voltage of the photoconductor drum after the image area has been exposed by the printhead;
• performing a first optimization to determine an adjusted dark voltage and an adjusted energy level based on the measured exposure voltage and the defined dark voltage and the energy levels applied to the photoconductor drum, wherein performing the first optimization comprises performing a non-linear analysis to select the adjusted energy level and the adjusted dark voltage such that the measured exposure voltage of the photoconductor drum is approximately linear with respect to the adjusted energy level;
• applying an applicator voltage to the applicator that applies toner to the exposed image area of the photoconductor drum;
• measuring toner density of the toner applied to the photoconductor drum;
• and
• performing a second optimization to adjust the applicator voltage to produce a target toner density.