Dialyte lens

Compound lens design that corrects optical aberrations where the lens elements are widely air-spaced.

- Dialyte lens

8 related topics

A 150 mm aperture catadioptric Maksutov telescope

Catadioptric system

One where refraction and reflection are combined in an optical system, usually via lenses and curved mirrors (catoptrics).

Light path in a meniscus telescope (Maksutov–Cassegrain)

Houghton doublet corrector design equations – special case symmetric design.

Light path in an Argunov Cassegrain telescope

Example of a catadioptric lens using rear surfaced "mangin mirrors" (Minolta RF Rokkor-X 250mm f/5.6)

An example of 'iris blur' or bokeh produced by a catadioptric lens, behind an in-focus light.

500 mm catadioptric lens mounted on a Yashica FX-3

Minolta AF 500 mm F/8 catadioptric lens mounted on a Sony Alpha 55 camera

Catadioptric dialytes are the earliest type of catadioptric telescope.

Chromatic aberration of a single lens causes different wavelengths of light to have differing focal lengths.

Achromatic lens

Lens that is designed to limit the effects of chromatic and spherical aberration.

An achromatic doublet brings red and blue light to the same focus, and is the earliest example of an achromatic lens.

In an achromatic lens, two wavelengths are brought into the same focus, here red and blue.

Dialyte lenses have a wide air space between the two elements.

John Wall (inventor)

English design engineer, amateur astronomer, amateur telescope maker and member of the British Astronomical Association.

$30-inch dialyte refracting telescope$

He is also known for designing dialyte based refracting telescopes, coming up with the Zerochromat retrofocally corrected refractor, including a folded 30-inch f/12 version he built in 1999.

Different kinds of camera lenses, including wide angle, telephoto and speciality

Celor lens

A Celor lens (also known as a symmetric dialyte) is a highly corrected lens of the Dialyt type, designed for process photography, involving reproduction at or near 1:1 scale.

Doublet (lens)

Type of lens made up of two simple lenses paired together.

An old Carl Zeiss Tessar camera lens with four elements, comprising two doublets. The front doublet is air-gapped and divergent; the rear doublet is glued and convergent. This arrangement was better at correcting spherical and chromatic aberrations and astigmatism than previous lens designs.

A sub-type of air-spaced doublet is the dialyte, a design where elements are widely spaced to save on the amount of glass used or where the elements cannot be cemented because they have strongly dissimilar curvatures.

Joseph Petzval

Mathematician, inventor, and physicist best known for his work in optics.

Diagram of Petzval's 1841 portrait lens - crown glass shaded pink, flint glass shaded blue

Modern Petzval objective lenses from a projector

The latter's lenses were marketed in Austria as the "photographic Dialyt", while Voigtländer marketed the lenses in Germany and Austria as the "Voightländer Orthoskop".

List of lens designs

This list covers optical lens designs grouped by tasks or overall type.

Dialyte lens

$A 200 mm refracting telescope at the Poznań Observatory$

Refracting telescope

Type of optical telescope that uses a lens as its objective to form an image (also referred to a dioptric telescope).

$A 200 mm refracting telescope at the Poznań Observatory$

Optical diagram of Galilean telescope
y – Distant object; y′ – Real image from objective; y″ – Magnified virtual image from eyepiece;
D – Entrance pupil diameter; d – Virtual exit pupil diameter; L1 – Objective lens; L2 – Eyepiece lens e – Virtual exit pupil – Telescope equals

$Engraved illustration of a 150 ft focal length Keplerian astronomical refracting telescope built by Johannes Hevelius.$

Alvan Clark polishes the big Yerkes achromatic objective lens, over 1 meter across, in 1896.

$This 12 inch refractor is mounted in dome and a mount the rotates with the turn of the Earth$

$The Greenwich 28-inch refractor is a popular tourist attraction in 21st century London$

The Apochromatic lens usually comprises three elements that bring light of three different frequencies to a common focus

$The 102 cm refractor, at Yerkes Observatory, the largest achromatic refractor ever put into astronomical use (photo taken on 6 May 1921, as Einstein was visiting)$

The "Große Refraktor" a double telescope with a 80cm (31.5") and 50 cm (19.5") lenses, was used to discover calcium as an interstellar medium in 1904.

Astronaut trains with camera with large lens

Touristic telescope pointed to Matterhorn in Switzerland

$The Yerkes Great refractor mounted at the 1893 World's Fair in Chicago; the tallest, longest, and biggest aperture refactor up to that time.$

$The 68 cm refractor at the Vienna University Observatory$

John Wall (30 in) dialyte refracting telescope - the largest refractor built by an individual, at Hanwell Community Observatory