To address issues related to the accurate control of infrared band film thickness and precise wavelength positioning, we employ the LabVIEW programming language to develop a dynamic monitoring and compensation technology for optical film thickness, based on an optical film thickness monitoring system. Based on the principles of light interference and optical thin film design, a mathematical model is constructed using the photoelectric polarimetric method. We focus on resolving stopping errors and filtering noise at extremum points, thereby accurately restoring the real-time monitoring data of light intensity. The system achieves real-time and synchronous fitting of the film’s transmittance curve, calculates and fits the stopping point corresponding to the extremum of the film thickness. To validate the reliability and stability of the optical control system, a 1064 nm narrow-band filter film was fabricated. The results indicate that the peak transmittance of the 1064 nm narrow-band filter film reached 91.5%, with a pass-band half-width of 5 nm. The error of the monitoring system was calculated to be less than 0.01%.