Shutter Glasses Confidentiality via Orthogonal Code Synchronization

The patent applies asymmetry by assigning different orthogonal codes to different users or different confidential images. Each user receives a specific orthogonal code that defines a unique shutter control pattern, making the system asymmetric and non-interchangeable. When user A uses their designated orthogonal code, they can only view their assigned confidential images during the periods when their shutter is open. Even if user A adjusts the shutter phase, they cannot view user B's confidential images because user B's images are displayed during periods when user A's shutter should be closed according to user A's orthogonal code pattern. This asymmetric code assignment ensures confidentiality while maintaining viewing flexibility for the intended user.

The patent uses orthogonal codes as an intermediary mechanism that mediates between the display system and the shutter glasses. The orthogonal code acts as a control signal that synchronizes the shutter operation with the image display sequence. This intermediary ensures that only the correct confidential images are visible during the periods when the shutter is open, preventing unauthorized viewing even if the shutter phase is adjusted. The orthogonal code intermediary maintains the relationship between display timing and shutter timing, ensuring confidentiality is preserved.

The patent applies periodic action by using orthogonal codes to define regular, predictable timing patterns for shutter opening and closing. These periodic patterns are synchronized with the display refresh rate and are designed to avoid flicker frequencies that are perceptible to humans. The periodic nature of orthogonal code-based control ensures that the shutter opens and closes at consistent intervals that match the display timing, eliminating random timing variations that could cause flicker while maintaining confidentiality through the structured code patterns.

The patent applies parameter changes by carefully selecting the frequency and timing parameters of the orthogonal code-based shutter control. The control system adjusts the timing parameters to ensure that the shutter operation frequency is high enough to avoid visible flicker (typically above the human flicker fusion threshold) while maintaining synchronization with the display refresh rate. By changing and optimizing these temporal parameters, the system eliminates flicker detection while preserving the confidentiality benefits of controlled shutter timing.