One dimensional linear fiber array is made by placing M / MM / PM fibers on a V-grooved substrate at specified spacing ( pitch ). As for these V groove fiber optic array, or the so-called optical V groove array, they are normally fixed into the grooves with epoxy and pressed by a glass cover. The optical fiber array facet of the optical fiber V groove array is always polished to meet the desired precision and during the production, active alignment is also used to ensure the correct alignment of fibers so that the fibers can be arranged in a certain order to form an optical fiber array block .