Albert Bouwers
Encyclopedia
Albert A. Bouwers was a Dutch
optical engineer
. He is known for developing and working with X-Rays and various optical technologies as a high-level researcher at Philips
research labs. He is lesser known for patenting in 1941 a catadioptric
meniscus telescope design similar to but slightly predating the Maksutov telescope
.
in the Netherlands in 1893. He obtained his Ph.D.
from Utrecht University
in 1924, with a dissertation entitled in Dutch Over het meten der intensiteit van Röntgenstralen He was also the director of the Philips
Laboratory's X-Ray Department.
Bouwers developed a night vision device for viewing in low light conditions, called the "night eye". The design used a photosensitive layer of cesium and antimony
in a cathode-ray tube, to brighten images by over 1,000 times. Unlike active infrared systems, it did not require an infrared flashlight. The design was initially produced by Olde Delft Optical Company in the Netherlands.
optician Dmitri Dmitrievich Maksutov
's 1941 Maksutov telescope
. War time secrecy kept Bouwers and Maksutov from knowing about each others designs and Bouwers’ design was not published until after World War II. Bouwers original design (based on an earlier catadioptric telescope, Bernhard Schmidt
's "Schmidt camera
") had the spherical mirror and spherical "meniscus corrector shell
" all with a common radius of curvature (a concentric or monocentric design). Like the Schmidt camera, the meniscus telescope has the aperture stop coincide with the center of curvature. It also shares the Schmidt's curved image plane. The design has an ultra wide field of view with no spherical aberration but does not correct chromatic aberration
and was only suitable as a monochromatic astronomical astrographic camera
working at a single wavelength of light. Bouwers came up with a later design that used a cemented doublet
to form the meniscus corrector shell to correct chromatic aberration
.
Dutch people
The Dutch people are an ethnic group native to the Netherlands. They share a common culture and speak the Dutch language. Dutch people and their descendants are found in migrant communities worldwide, notably in Suriname, Chile, Brazil, Canada, Australia, South Africa, New Zealand, and the United...
optical engineer
Optical engineering
Optical engineering is the field of study that focuses on applications of optics. Optical engineers design components of optical instruments such as lenses, microscopes, telescopes, and other equipment that utilizes the properties of light. Other devices include optical sensors and measurement...
. He is known for developing and working with X-Rays and various optical technologies as a high-level researcher at Philips
Philips
Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....
research labs. He is lesser known for patenting in 1941 a catadioptric
Catadioptric
A catadioptric optical system is one where refraction and reflection are combined in an optical system, usually via lenses and curved mirrors . Catadioptric combinations are used in focusing systems such as search lights, headlamps, early lighthouse focusing systems, optical telescopes,...
meniscus telescope design similar to but slightly predating the Maksutov telescope
Maksutov telescope
The Maksutov is a catadioptric telescope design that combines a spherical mirror with a weakly negative meniscus lens in a design that takes advantage of all the surfaces being nearly "spherically symmetrical". The negative lens is usually full diameter and placed at the entrance pupil of the...
.
Biography
Bouwers was born in the town of DalenDalen
Dalen is an old village and a former municipality in the northeastern Netherlands, in the province of Drenthe. Since 1998, Dalen has been part of the municipality of Coevorden....
in the Netherlands in 1893. He obtained his Ph.D.
Doctor of Philosophy
Doctor of Philosophy, abbreviated as Ph.D., PhD, D.Phil., or DPhil , in English-speaking countries, is a postgraduate academic degree awarded by universities...
from Utrecht University
Utrecht University
Utrecht University is a university in Utrecht, Netherlands. It is one of the oldest universities in the Netherlands and one of the largest in Europe. Established March 26, 1636, it had an enrollment of 29,082 students in 2008, and employed 8,614 faculty and staff, 570 of which are full professors....
in 1924, with a dissertation entitled in Dutch Over het meten der intensiteit van Röntgenstralen He was also the director of the Philips
Philips
Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....
Laboratory's X-Ray Department.
Bouwers developed a night vision device for viewing in low light conditions, called the "night eye". The design used a photosensitive layer of cesium and antimony
Antimony
Antimony is a toxic chemical element with the symbol Sb and an atomic number of 51. A lustrous grey metalloid, it is found in nature mainly as the sulfide mineral stibnite...
in a cathode-ray tube, to brighten images by over 1,000 times. Unlike active infrared systems, it did not require an infrared flashlight. The design was initially produced by Olde Delft Optical Company in the Netherlands.
Bouwers meniscus telescope
In August 1940 Albert Bouwers built a prototype for a design for a wide field concentric meniscus telescope (patented February 1941) similar to, and slightly predating, RussianRussians
The Russian people are an East Slavic ethnic group native to Russia, speaking the Russian language and primarily living in Russia and neighboring countries....
optician Dmitri Dmitrievich Maksutov
Dmitri Dmitrievich Maksutov
Dmitry Dmitrievich Maksutov was a Russian / Soviet optical engineer and amateur astronomer. He is best known as the inventor of the Maksutov telescope.-Biography:...
's 1941 Maksutov telescope
Maksutov telescope
The Maksutov is a catadioptric telescope design that combines a spherical mirror with a weakly negative meniscus lens in a design that takes advantage of all the surfaces being nearly "spherically symmetrical". The negative lens is usually full diameter and placed at the entrance pupil of the...
. War time secrecy kept Bouwers and Maksutov from knowing about each others designs and Bouwers’ design was not published until after World War II. Bouwers original design (based on an earlier catadioptric telescope, Bernhard Schmidt
Bernhard Schmidt
Bernhard Woldemar Schmidt was a German optician. In 1930 he invented the Schmidt telescope which corrected for the optical errors of spherical aberration, coma, and astigmatism, making possible for the first time the construction of very large, wide-angled reflective cameras of short exposure time...
's "Schmidt camera
Schmidt camera
A Schmidt camera, also referred to as the Schmidt telescope, is a catadioptric astrophotographic telescope designed to provide wide fields of view with limited aberrations. Other similar designs are the Wright Camera and Lurie-Houghton telescope....
") had the spherical mirror and spherical "meniscus corrector shell
Meniscus corrector
A meniscus corrector is a negative meniscus lens that is used to correct spherical aberration in image-forming optical systems such as catadioptric telescopes...
" all with a common radius of curvature (a concentric or monocentric design). Like the Schmidt camera, the meniscus telescope has the aperture stop coincide with the center of curvature. It also shares the Schmidt's curved image plane. The design has an ultra wide field of view with no spherical aberration but does not correct chromatic aberration
Chromatic aberration
In optics, chromatic aberration is a type of distortion in which there is a failure of a lens to focus all colors to the same convergence point. It occurs because lenses have a different refractive index for different wavelengths of light...
and was only suitable as a monochromatic astronomical astrographic camera
Astrograph
An astrograph is a telescope designed for the sole purpose of astrophotography. Astrographs are usually used in wide field surveys of the night sky as well as detection of objects such as asteroids, meteors, and comets.-Design:...
working at a single wavelength of light. Bouwers came up with a later design that used a cemented doublet
Doublet (lens)
In optics, a doublet is a type of lens made up of two simple lenses paired together. Such an arrangement allows more optical surfaces, thicknesses, and formulations, especially as the space between lenses may be considered an "element." With additional degrees of freedom, optical designers have...
to form the meniscus corrector shell to correct chromatic aberration
Chromatic aberration
In optics, chromatic aberration is a type of distortion in which there is a failure of a lens to focus all colors to the same convergence point. It occurs because lenses have a different refractive index for different wavelengths of light...
.