Stanhope lens
Encyclopedia
A Stanhope lens is a simple, one-piece microscope
invented by Charles, the third Earl of Stanhope
. It is a cylinder
of glass
with each end curved outwards, one being more convex than the other. The focal length of the apparatus is at or within the device so that objects to be studied are placed close to or in contact with the less curved end. A magnification
of 4096 may be obtained, so revealing the detail of microorganism
s. Because its construction is simple and economical, it was popular in the 19th century. It was useful in medical practise
for examining transparent
materials such as crystal
s and fluid
s.
René Dagron
modified the lens by keeping one curved end to refract light while sectioning the other end flat and locating it at the focal plane of the curved side. Dagron used the modified Stanhope lens in mounting his microscopic pictures in photographic jewels known as Stanhopes
.
A rival lens is the Coddington magnifier
. This was considered superior as a magnifier but was more expensive.
Microscope
A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy...
invented by Charles, the third Earl of Stanhope
Charles Stanhope, 3rd Earl Stanhope
Charles Stanhope, 3rd Earl Stanhope aka Charles Mahon, 3rd Earl Stanhope FRS was a British statesman and scientist. He was the father of the great traveller and Arabist Lady Hester Stanhope and brother-in-law of William Pitt the Younger. He is sometimes confused with an exact contemporary of his,...
. It is a cylinder
Cylinder (geometry)
A cylinder is one of the most basic curvilinear geometric shapes, the surface formed by the points at a fixed distance from a given line segment, the axis of the cylinder. The solid enclosed by this surface and by two planes perpendicular to the axis is also called a cylinder...
of glass
Glass
Glass is an amorphous solid material. Glasses are typically brittle and optically transparent.The most familiar type of glass, used for centuries in windows and drinking vessels, is soda-lime glass, composed of about 75% silica plus Na2O, CaO, and several minor additives...
with each end curved outwards, one being more convex than the other. The focal length of the apparatus is at or within the device so that objects to be studied are placed close to or in contact with the less curved end. A magnification
Magnification
Magnification is the process of enlarging something only in appearance, not in physical size. This enlargement is quantified by a calculated number also called "magnification"...
of 4096 may be obtained, so revealing the detail of microorganism
Microorganism
A microorganism or microbe is a microscopic organism that comprises either a single cell , cell clusters, or no cell at all...
s. Because its construction is simple and economical, it was popular in the 19th century. It was useful in medical practise
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
for examining transparent
Transparency and translucency
In the field of optics, transparency is the physical property of allowing light to pass through a material; translucency only allows light to pass through diffusely. The opposite property is opacity...
materials such as crystal
Crystal
A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...
s and fluid
Fluid
In physics, a fluid is a substance that continually deforms under an applied shear stress. Fluids are a subset of the phases of matter and include liquids, gases, plasmas and, to some extent, plastic solids....
s.
René Dagron
René Dagron
René Prudent Patrice Dagron was a French photographer and inventor. He was born in Aillières-Beauvoir, Sarthe, France....
modified the lens by keeping one curved end to refract light while sectioning the other end flat and locating it at the focal plane of the curved side. Dagron used the modified Stanhope lens in mounting his microscopic pictures in photographic jewels known as Stanhopes
Stanhope (optical bijou)
Stanhopes or Stanho-scopes are optical devices that enable the viewing of microphotographs without using a microscope. They were invented by René Dagron in 1857. Dagron bypassed the need for an expensive microscope to view the microscopic photographs by attaching the microphotograph at the end of a...
.
A rival lens is the Coddington magnifier
Coddington magnifier
A Coddington magnifier is a magnifying glass consisting of a single very thick lens with a central deep groove diaphragm at the equator, thus limiting the rays to those close to the axis, which again minimizes spherical aberration. This allows for greater magnification than a conventional...
. This was considered superior as a magnifier but was more expensive.