Imaging Device Light Sensitivity Calibration via Shutter Lag Compensation

The patent implements a feedback mechanism where the mechanical shutter calibration result is used to correct the light sensitivity calibration. The system captures images at different exposure times, calculates the actual lag time from the mechanical shutter calibration, and uses this information to compensate for errors in light sensitivity calibration. This feedback loop ensures that both calibrations are performed with high accuracy despite the interdependence problem.

The patent performs light sensitivity calibration at multiple exposure times (first exposure time and second exposure time) rather than a single exposure time. By capturing images at different exposure conditions and performing differential calculation, the system obtains more accurate calibration results that compensate for mechanical shutter lag time errors, effectively using excessive measurement actions to improve precision.

The patent performs mechanical shutter calibration first to obtain the actual lag time, and then uses this information to correct the light sensitivity calibration results. By performing the mechanical shutter calibration as a preliminary action, the system establishes an accurate reference for subsequent light sensitivity calibration, eliminating the error propagation that would occur if light sensitivity were calibrated first with incorrect lag time assumptions.

The patent introduces the mechanical shutter calibration result as an intermediary element that mediates between the exposure time settings and the final light sensitivity calibration. The actual lag time obtained from mechanical shutter calibration serves as an intermediary parameter that corrects the light sensitivity calibration calculations, ensuring accurate results even when calibrating in a sequence where mechanical shutter calibration is performed first.

The patent compensates for mechanical shutter lag time by using electronic shutter control with calculated correction values. The system determines the actual mechanical shutter lag time through calibration and then uses electronic shutter timing adjustments to compensate for this lag, effectively replacing the imperfect mechanical timing with more precise electronic timing control while maintaining the benefits of mechanical shutter isolation.

The patent changes the exposure time parameter by subtracting the measured mechanical shutter lag time from the intended exposure time. This parameter adjustment ensures that the actual exposure duration matches the intended duration, compensating for the mechanical shutter lag and improving exposure accuracy while maintaining the ease of operation provided by mechanical shutter control.