Cornea Stiffness Correction for Intraocular Pressure

The patent applies parameter changes by measuring multiple corneal parameters (thickness, curvature radii, elastic modulus) and using these to correct the non-contact tonometer measurement. The system transforms the raw non-contact measurement into an accurate intraocular pressure value by adjusting for corneal biomechanical properties, thereby maintaining contactless operation while achieving measurement accuracy comparable to contact methods.

The patent implements local quality by determining the elastic modulus individually for each cornea being measured, rather than assuming a universal constant. The system measures corneal thickness and curvature at specific locations and calculates the elastic modulus specific to that patient's corneal tissue, thereby accounting for individual anatomical variations and improving measurement accuracy without significantly increasing procedural complexity.

The patent applies feedback by continuously monitoring the actual time course of the air blast pressure and the measured corneal deformation, then using this information to calculate and correct for dynamic effects. The system measures the pump pressure continuously with a pressure sensor and correlates it with the optical detection of applanation points, allowing real-time compensation for dynamic corneal vibrations and enabling accurate measurements even with higher air blast velocities.

The patent replaces the mechanical timing approach with an optical sensing system that directly detects corneal applanation events. Instead of relying on mechanical pump timing, the system uses optical sensors to detect when applanation occurs and correlates this with the continuously recorded pressure data, eliminating synchronization errors caused by mechanical inertia and friction.