How should the temple length be correctly measured?

The correct method for measuring the temple length is from the screw hole to the ear, including around the ear. This measurement is crucial for ensuring that the eyewear fits comfortably and securely on the wearer. By taking this measurement, you account for the natural curvature of the ear and allow for a comfortable fit that keeps the glasses in place without causing discomfort or slipping.

Measuring from the screw hole is important because it represents the functional point where the temple attaches to the frame, ensuring that the overall length supports a proper alignment with the wearer's face. Including the measurement around the ear helps in achieving a snug fit, accommodating the anatomy of the wearer's head and ears.

In contrast, the other methods, such as measuring from the front of the frame to the back or from the end of the temple to the front of the frame, do not adequately account for the dynamics of how eyewear interacts with the head when being worn. Additionally, measuring from the middle of the bridge to the end of the temple does not capture the necessary context for a proper fit, as it ignores the overall structure the temple must navigate around to maintain a secure position on the wearer’s head.