You may be thinking of a Fresnel Lens. This is a lens of large diameter, but which is made to be compact size and weight by consisting of a series of concentric circular prisms. This still behaves as a large diameter lens, but with much reduced mass.
The Fresnel Lens was originally developed by French physicist Augustin-Jean Fresnel. It is a type of compact lens used to project light within a lighthouse.
A fresnel lens is a type of magnifying glass itself. NOT the most familiar type like sherlock holmes used. You can find fresnel lenses stuck to the back window of vans, in lighthouse lenses. any magnifying lens that has concentric ridges to achieve the magnification effect only using a thin lens.
It is a lighthouse.
The type of lense is a convex lense
Another type of lens is the opposite called a reducing lens.
convex lens
The setting of the poem "A Stone's Throw" is a rural farming community, with imagery of fields, stones, and farmers working the land. The poem explores themes of distance and connection between people in this setting.
Fresnel lens
convex... gago
a convex lens
ocular lens
Convex lens .