What does a front surface mirror provide when measuring reflection?

A front surface mirror is designed to reflect light off its surface rather than through it, which minimizes distortion and provides a clearer image. When measuring reflection, this type of mirror ensures that the image is a true representation of the distance between the object and the mirror. This is particularly important in optical measurements, as it gives accurate spatial relationships that can be quantified. By keeping the reflected image free from the distortions that may occur in other types of mirrors, the front surface mirror allows for precise assessments that are crucial in various ophthalmic procedures and diagnostics.