What is the primary function of a library temple?

The primary function of a library temple is to stabilize the frame by applying pressure to the side of the head. This type of temple extends straight back along the side of the head and provides a snug fit, which helps keep the eyewear securely in place. The design allows for a more secure grip without requiring additional materials or adjustments, making it particularly useful for individuals who engage in physical activities or have a tendency to move their heads frequently.

Other options, while relevant to the design of eyewear, serve different purposes. For instance, flexibility behind the ear can be associated with more flexible temple designs that may not be typical of a library temple. A deep grooved front for comfort typically refers to the aesthetics rather than stability. Lastly, the support of the lower part of the nosepad is generally associated with the frame's bridge design, rather than the temple structure itself. This differentiation is important for understanding the roles different parts of eyewear play in functionality.