Lippmann process photography is an early

color photography Color photography (also spelled as colour photography in English in the Commonwealth of Nations, Commonwealth English) is photography that uses media capable of capturing and reproducing colors. By contrast, black-and-white or gray-monochrome ...

method and type of

alternative process The term alternative process refers to any non-traditional or non-commercial photographic printing process. Currently, the standard analog photographic printing process for black-and-white photographs is the gelatin silver process. Standard dig ...

photography. It was invented by French scientist

Gabriel Lippmann Gabriel Lippmann ( ; 16 August 1845 – 12 July 1921) was a French physicist who received the Nobel Prize in Physics in 1908 "for his method of reproducing colours photographically based on the phenomenon of interference". Early life and educa ...

in 1891 and consists of first focusing an image onto a light-sensitive plate, placing the

emulsion An emulsion is a mixture of two or more liquids that are normally Miscibility, immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloi ...

in contact with a mirror (originally liquid mercury) during the exposure to introduce

interference Interference is the act of interfering, invading, or poaching. Interference may also refer to: Communications * Interference (communication), anything which alters, modifies, or disrupts a message * Adjacent-channel interference, caused by extra ...

, chemically developing the plate, inverting the plate and painting the glass black, and finally affixing a

prism PRISM is a code name for a program under which the United States National Security Agency (NSA) collects internet communications from various U.S. internet companies. The program is also known by the SIGAD . PRISM collects stored internet ...

to the emulsion surface. The image is then viewed by illuminating the plate with light. This type of photography became known as interferential photography or interferometric colour photography and the results it produces are sometimes called direct photochromes, interference photochromes, or Lippmann photochromes (distinguished from the earlier so-called " photochromes" which were merely black-and-white photographs painted with color by hand). In French, the method is known as '' photographie interférentielle'' and the resulting images were originally exhibited as ''des vues lippmaniennes''. Lippmann won the

Nobel Prize in Physics The Nobel Prize in Physics () is an annual award given by the Royal Swedish Academy of Sciences for those who have made the most outstanding contributions to mankind in the field of physics. It is one of the five Nobel Prizes established by the ...

in 1908 "for his method of reproducing colours photographically based on the phenomenon of interference". Images made with this method are created on a Lippmann plate: a clear glass plate (having no

anti-halation backing An anti-halation backing is a layer found in many photographic films—and almost all film intended for motion picture cameras—usually a coating on the back of the film base, though it is sometimes incorporated between the light-sensitive photo ...

), coated with an almost transparent (very low silver halide content)

of extremely fine grains, typically 0.01 to 0.04 micrometres in diameter. Consequently, Lippmann plates have an extremely high resolving power exceeding 400 lines/mm.

Method

In Lippmann's method, a glass plate is coated with an ultra fine grain light-sensitive film (originally using the albumen process containing

potassium bromide Potassium bromide ( K Br) is a salt, widely used as an anticonvulsant and a sedative in the late 19th and early 20th centuries, with over-the-counter use extending to 1975 in the US. Its action is due to the bromide ion ( sodium bromide is equa ...

; later and primarily using silver halide gelatin), then dried, sensitized in the silver bath, washed, irrigated with cyanine solution, and dried again. The back of the film is then brought into optical contact with a reflective surface. This originally was done by mounting the plate in a specialized holder with pure mercury behind the film. When it is exposed in the camera through the glass side of the plate, the light rays which strike the transparent light-sensitive film are reflected back on themselves and, by interference, create

standing wave In physics, a standing wave, also known as a stationary wave, is a wave that oscillates in time but whose peak amplitude profile does not move in space. The peak amplitude of the wave oscillations at any point in space is constant with respect t ...

s. The standing waves cause exposure of the emulsion in diffraction patterns. The developed and fixated diffraction patterns constitute a

Bragg condition In many areas of science, Bragg's law — also known as Georg Wulff, Wulff–Bragg's condition or Laue–Bragg interference — is a special case of Laue diffraction that gives the angles for coherent scattering of waves from a large crystal lattic ...

in which diffuse, white light is scattered in a specular fashion and undergoes constructive interference in accordance to Bragg's law. The result is an image having very similar colours as the original using a black and white photographic process. For this method Lippmann won the

in 1908. The colour image can only be viewed in the reflection of a diffuse light source from the plate, making the

field of view The field of view (FOV) is the angle, angular extent of the observable world that is visual perception, seen at any given moment. In the case of optical instruments or sensors, it is a solid angle through which a detector is sensitive to elec ...

limited, and therefore not easily copied with conventional techniques. The method was very insensitive with the emulsions of the time and it never came into general use. Another reason Lippmann's process of colour photography did not succeed can be found in the invention of the autochrome plates by the

Lumière brothers Lumière is French for 'light'. Lumiere, Lumière or Lumieres may refer to: Buildings * Lumière, a building used by the Bibliothèque publique d'information in Paris, France * Lumiere (skyscraper), a cancelled skyscraper development in Leeds, ...

. A technique derived from the Lippmann technique has been proposed as a method of producing images which can easily be viewed, but not copied, for security purposes.

Gallery

File:Lippmann Still life.jpg, A still life by Lippmann File:Lippmann Venice.jpg,

Venice Venice ( ; ; , formerly ) is a city in northeastern Italy and the capital of the Veneto Regions of Italy, region. It is built on a group of 118 islands that are separated by expanses of open water and by canals; portions of the city are li ...

by Lippmann File:Lippmann Saas Fee.jpg,

Saas-Fee Saas-Fee () is the main village in the Saastal, or the Saas Valley, and is a municipality in the district of Visp in the canton of Valais in Switzerland. The village is situated on a high mountain plateau at 1,800 meters (5,900 feet), surrounded ...

by Lippmann File:Parrot photo made by Gabriel Lippmann in 1891.jpg, An 1899 interferential photograph of a stuffed parrot made by File:Bouquet de Fleurs-laboratoire de physique de la faculté des sciences de Lille par Auguste Ponsot vers 1905.png, A 1906 interferential photograph by , Lippmann's student and colleague

Other sources of Lippmann plates

* The Kodak Spectroscopic Plate Type 649-F is specified with a resolving power of 2000 lines/mm. * A diffusion method for making silver bromide based holographic recording material was published.

Durable data storage utility

Because the photographs are so durable, researchers have reworked Lippmann plates for use in archival data storage to replace

hard drives A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...

. Work began on the project after they were made aware data storage on the

International Space Station The International Space Station (ISS) is a large space station that was Assembly of the International Space Station, assembled and is maintained in low Earth orbit by a collaboration of five space agencies and their contractors: NASA (United ...

requires daily maintenance because it can be damaged by

cosmic rays Cosmic rays or astroparticles are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Solar ...

and they recalled that silver halide would not be significantly affected by astroparticles (or even

electromagnetic pulses An electromagnetic pulse (EMP), also referred to as a transient electromagnetic disturbance (TED), is a brief burst of electromagnetic energy. The origin of an EMP can be natural or artificial, and can occur as an electromagnetic field, as an ...

from nuclear explosions). 150 standing-wave storage samples placed on the ISS during 2019 showed no signs of data degradation after exposure to cosmic rays for nine months.

References

External links