The length of the eyeball (either longer or shorter), changes in the shape of the cornea, or aging of the lens can cause refractive errors. Most people have one or more of these conditions. The cornea and lens bend (refract) incoming light rays so they focus precisely on the retina at the back of the eye.
BF series Composite strain gauge. This gauge is designed for measurement on composite materials. It has a specially designed grid configuration to reduce the tightening effect of the gauge to the specimen. As the temperature compensation is available for material with thermal expansion coefficient of 3, 5 or 8ppm/Â°C, this series is recommendable for ceramic, carbon, and composite materials.
Definition. A composite is when two or more different materials are combined together to create a superior and unique material. This is an extremely broad definition that holds true for all composites, however, more recently the term composite describes reinforced plastics.Background on Composites.xamples of Composites. The most common example of a composite in a broad sense is concrete. In this use, structural steel rebar provides the strength and stiffness to the concrete, while the cured cement holds the rebar stationary.