Stabilization of color/tone reproduction curves using time-sequential sampling

In xerographic printing, stabilization of the color reproduc-tion function (CRC) or the tone reproduction curve (TRC) for the color separations are critical for achieving color consistency. This problem is challenging because: 1) there exist only a small number of actuators to stabilize a po-tentially infinite dimensional TRC; 2) only a small number of tone / color test patches can be printed and measured at a time. The first issue is addressed by a curve-fitting TRC stabilization controller based on Linear Quadratic (LQ) con-trol with integral dynamics is proposed. It specifies partic-ular tones or color that to be precisely controlled, while allowing other tones or colors to be close to the desired value. To address the second problem, time-sequential sampling is proposed to enable the time varying TRC or CRC to be reconstructed based on small number of sam-ples. Experimental and simulation results verify the ade-quacy of the approach