This arrangement is known as a Fresnel lens. The reflector was later replaced by a Fresnel lens. The PIR sensor consists of a pyroelectric sensor and a Fresnel lens. The light, magnified by a third-order Fresnel lens, has a range of . Each individual facet is a Fresnel lens. A first-order Fresnel lens was installed. The tower housed a Fourth Order Fresnel lens. The lighthouse was originally fitted with first-order Fresnel lens. Its Fourth Order Fresnel lens remains a valuable aid to navigation. The lighthouse was equipped with a third-order Fresnel lens. Lenses are frequently made in multiple sections, like a Fresnel lens. The new light was a first-order flashing Fresnel lens, which stood about tall. The fourth order Fresnel lens was first lit on December 10, 1856. Great lengths were taken to protect the valuable Fresnel lens during the restoration. On 25 July 1823, the world's first lighthouse Fresnel lens was lit.