Profile control method and system therefor

Abstract

A profile control method for controlling a profile in the width direction of a sheet by using a plurality of actuators, includes calculating an envelope profile connecting local peaks of the profile; and calculating a manipulated value of each actuator with the objective of optimizing 2σ of the profile and the envelope profile.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram illustrating a film forming system including a profile control system in one embodiment of the present invention.

FIG. 2 is a detailed view illustrating a T die 2 of the film forming system in one embodiment of the present invention.

FIG. 3 is a flowchart illustrating actions of the film forming system including a profile control system in one embodiment of the present invention.

FIG. 4 illustrates one example of a virtual actuator corresponding profile P(i) and an envelope profile EP(i) in one embodiment of the present invention.

FIG. 5 illustrates the result of a simulation where the profile control in one embodiment of the present invention is not carried out.

FIG. 6 illustrates the result of a simulation where the profile control in one embodiment of the present invention is carried out.

Claims

1. A profile control method for controlling a profile in the width direction of a sheet by using a plurality of actuators, comprising: calculating an envelope profile connecting local peaks of the profile; andcalculating a manipulated value of each actuator with the objective of optimizing 2σ of the profile and the envelope profile.

2. A profile control method according to claim 1, further comprising applying the steepest descent method relating to an evaluation function of optimizing 2σ of the profile and the envelope profile.

3. A profile control method according to claim 2, wherein the evaluation function is obtained by adding an evaluation function of the envelope profile containing a predetermined weighting factor to the evaluation function of the profile, and an optimization ratio of the profile to the envelope profile is adjusted by adjusting the weighting factor.

4. A system of controlling a profile in the width direction of a sheet by using a plurality of actuators, comprising: a profile controller by using a profile measured in the width direction of the sheet to calculate an envelope profile connecting local peaks of the profile, thereby calculating a manipulated value of each actuator with the objective of optimizing 2σ of the profile and the envelope profile.