Stereoscope

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Old Zeiss pocket stereoscope with original test image Pocket stereoscope.jpg
Old Zeiss pocket stereoscope with original test image
A common Underwood & Underwood Stereoscope U&U Stereoscope (02).jpg
A common Underwood & Underwood Stereoscope

A stereoscope is a device for viewing a stereoscopic pair of separate images, depicting left-eye and right-eye views of the same scene, as a single three-dimensional image.

Contents

A typical stereoscope provides each eye with a lens that makes the image seen through it appear larger and more distant and usually also shifts its apparent horizontal position, so that for a person with normal binocular depth perception the edges of the two images seemingly fuse into one "stereo window". In current practice, the images are prepared so that the scene appears to be beyond this virtual window, through which objects are sometimes allowed to protrude, but this was not always the custom. A divider or other view-limiting feature is usually provided to prevent each eye from being distracted by also seeing the image intended for the other eye.

Most people can, with practice and some effort, view stereoscopic image pairs in 3D without the aid of a stereoscope, but the physiological depth cues resulting from the unnatural combination of eye convergence and focus required will be unlike those experienced when actually viewing the scene in reality, making an accurate simulation of the natural viewing experience impossible and tending to cause eye strain and fatigue.

Although more recent devices such as Realist-format 3D slide viewers, the View-Master or virtual reality headsets are also stereoscopes, the word is now most commonly associated with viewers designed for the standard-format stereo cards that enjoyed several waves of popularity from the 1850s to the 1930s as a home entertainment medium.

Devices such as polarized, anaglyph and shutter glasses which are used to view two actually superimposed or intermingled images, rather than two physically separate images, are not categorized as stereoscopes.

History

Wheatstone stereoscope

Wheatstone mirror stereoscope Charles Wheatstone-mirror stereoscope XIXc.jpg
Wheatstone mirror stereoscope

The earliest stereoscopes, "both with reflecting mirrors and with refracting prisms", were invented by Sir Charles Wheatstone and constructed for him by optician R. Murray in 1832. [1] Herbert Mayo shortly described Wheatstone's discovery in his book Outlines of Human Physiology (1833) and claimed that Wheatstone was about to publish an essay about it. [2] It was only one of many projects of Wheatstone's and he first presented his findings on 21 June 1838 to the Royal College of London. [3] [4] [5] In this presentation he used a pair of mirrors at 45 degree angles to the user's eyes, each reflecting a picture located off to the side. It demonstrated the importance of binocular depth perception by showing that when two pictures simulating left-eye and right-eye views of the same object are presented so that each eye sees only the image designed for it, but apparently in the same location, the brain will fuse the two and accept them as a view of one solid three-dimensional object. Wheatstone's stereoscope was introduced in the year before the first practical photographic processes became available, so initially drawings were used. The mirror type of stereoscope has the advantage that the two pictures can be very large if desired.

Brewster stereoscope

Brewster-type stereoscope, 1870 IGB 006055 Visore stereoscopico portatile Museo scienza e tecnologia Milano.jpg
Brewster-type stereoscope, 1870
Brewster stereoscope PSM V21 D055 The brewster stereoscope 1849.jpg
Brewster stereoscope

Contrary to a common assertion, David Brewster did not invent the stereoscope, as he himself was often at pains to make clear. [6] A rival of Wheatstone, Brewster credited the invention of the device to a Mr. Elliot, a "Teacher of Mathematics" from Edinburgh, who, according to Brewster, conceived of the idea as early as 1823 and, in 1839, constructed "a simple stereoscope without lenses or mirrors", consisting of a wooden box 18 inches (46 cm) long, 7 inches (18 cm) wide and 4 inches (10 cm) high, which was used to view drawn landscape transparencies, since photography had yet to become widespread. [7] Brewster's personal contribution was the suggestion to use lenses for uniting the dissimilar pictures in 1849; and accordingly the lenticular stereoscope (lens-based) may fairly be said to be his invention. [8] This allowed a reduction in size, creating hand-held devices, which became known as Brewster Stereoscopes, much admired by Queen Victoria when they were demonstrated at the Great Exhibition of 1851. [9]

Brewster was unable to find in Britain an instrument maker capable of working with his design, so he took it to France, where the stereoscope was improved by Jules Duboscq who made stereoscopes and stereoscopic daguerreotypes, and a famous picture of Queen Victoria that was displayed at The Great Exhibition. [8] Almost overnight a 3D industry developed and 250,000 stereoscopes were produced and a great number of stereoviews, stereo cards, stereo pairs or stereographs were sold in a short time. Stereographers were sent throughout the world to capture views for the new medium and feed the demand for 3D images. [10] Cards were printed with these views often with explanatory text when the cards were looked at through the double-lensed viewer, sometimes also called a stereopticon , a common misnomer.

Holmes stereoscope

A Holmes stereoscope, the most popular form of 19th century stereoscope Holmes stereoscope.jpg
A Holmes stereoscope, the most popular form of 19th century stereoscope

In 1861 Oliver Wendell Holmes created and deliberately did not patent a handheld, streamlined, much more economical viewer than had been available before. The stereoscope, which dates from the 1850s, consisted of two prismatic lenses and a wooden stand to hold the stereo card. This type of stereoscope remained in production for a century and there are still companies making them in limited production currently.

Multiple view stereoscope

Multiple view stereoscope for 45x107mm glass stereoviews, manufactured by Hemde. Hemde-serie1-stereoscope.jpg
Multiple view stereoscope for 45x107mm glass stereoviews, manufactured by Hemdé.

Multiple view stereoscopes allow viewing multiple stereoscopic images in sequence by turning a knob, crank or pushing down a lever. The first design was patented by Antoine Claudet in 1855, [11] but the design of Alexander Beckers from 1857 [11] formed the basis for many revolving stereoscopes that were manufactured from the 1860s. The images are placed in holders that are attached to a rotating belt. The belt can usually hold 50 paper card or glass stereoviews, but there are also large floor standing models for 100 or 200 views.

A more advanced multiple view stereoscope is only intended for glass slides and was especially popular in France, as the printing of stereo images on glass was a French specialty and popular until the 1930s. Most devices were manufactured in France, but also in Germany by ICA and Ernemann. The glass slides are placed in a bakelite or wooden tray. Turning a crank (or pushing down a lever) will lift a slide from the tray and brings it into viewing position. Turning further will place the slide back in the tray and moves the tray over a rail to select the next slide. The most sophisticated and well known design was the Taxiphote by Jules Richard, patented in 1899. [12]

Modern use

In the mid-20th century the View-Master stereoscope (patented 1939), with its rotating cardboard disks containing image pairs, was popular first for 'virtual tourism' and then as a toy. In 2010, Hasbro started producing a stereoscope designed to hold an iPhone or iPod Touch, called the My3D. In 2014, Google released the template for a papercraft stereoscope called Google Cardboard. Apps on the mobile phone substitute for stereo cards; these apps can also sense rotation and expand the stereoscope's capacity into that of a full-fledged virtual reality device. The underlying technology is otherwise unchanged from earlier stereoscopes.

Several fine arts photographers and graphic artists have and continue to produce original artwork to be viewed using stereoscopes.

Principles

Stereo card of a stereoscope in use (1901). () Stereograph as an educator.jpg
Stereo card of a stereoscope in use (1901). ( Stereogram guide parallel.png )

A simple stereoscope is limited in the size of the image that may be used. A more complex stereoscope uses a pair of horizontal periscope-like devices, allowing the use of larger images that can present more detailed information in a wider field of view. The stereoscope is essentially an instrument in which two photographs of the same object, taken from slightly different angles, are simultaneously presented, one to each eye. This recreates the way which in natural vision, each eye is seeing the object from a slightly different angle, since they are separated by several inches, which is what gives humans natural depth perception. Each picture is focused by a separate lens, and by showing each eye a photograph taken several inches apart from each other and focused on the same point, it recreates the natural effect of seeing things in three dimensions.

A moving image extension of the stereoscope has a large vertically mounted drum containing a wheel upon which are mounted a series of stereographic cards which form a moving picture. The cards are restrained by a gate and when sufficient force is available to bend the card it slips past the gate and into view, obscuring the preceding picture. These coin-enabled devices were found in arcades in the late 19th and early 20th century and were operated by the viewer using a hand crank. These devices can still be seen and operated in some museums specializing in arcade equipment.

The stereoscope offers several advantages:

Stereo card depicting children in front of the C.M. Wiley House, circa 1880. 285 College Street, C. M. Wiley house, circa 1880 - DPLA - 1e746f834dadfabfaec91480fc93dd70.jpg
Stereo card depicting children in front of the C.M. Wiley House, circa 1880.

A stereo transparency viewer is a type of stereoscope that offers similar advantages, e.g. the View-Master.

Disadvantages of stereo cards, slides or any other hard copy or print are that the two images are likely to receive differing wear, scratches and other decay. This results in stereo artifacts when the images are viewed. These artifacts compete in the mind resulting in a distraction from the 3D effect, eye strain and headaches.

See also

Related Research Articles

<span class="mw-page-title-main">Stereoscopy</span> Technique for creating or enhancing the illusion of depth in an image

Stereoscopy is a technique for creating or enhancing the illusion of depth in an image by means of stereopsis for binocular vision. The word stereoscopy derives from Greek στερεός (stereos) 'firm, solid', and σκοπέω (skopeō) 'to look, to see'. Any stereoscopic image is called a stereogram. Originally, stereogram referred to a pair of stereo images which could be viewed using a stereoscope.

3D films are motion pictures made to give an illusion of three-dimensional solidity, usually with the help of special glasses worn by viewers. They have existed in some form since 1915, but had been largely relegated to a niche in the motion picture industry because of the costly hardware and processes required to produce and display a 3D film, and the lack of a standardized format for all segments of the entertainment business. Nonetheless, 3D films were prominently featured in the 1950s in American cinema, and later experienced a worldwide resurgence in the 1980s and 1990s driven by IMAX high-end theaters and Disney-themed venues. 3D films became increasingly successful throughout the 2000s, peaking with the success of 3D presentations of Avatar in December 2009, after which 3D films again decreased in popularity. Certain directors have also taken more experimental approaches to 3D filmmaking, most notably celebrated auteur Jean-Luc Godard in his film Goodbye to Language.

<span class="mw-page-title-main">Autostereogram</span> Visual illusion of 3D scene achieved by unfocusing eyes when viewing specific 2D images

An autostereogram is a two-dimensional (2D) image that can create the optical illusion of a three-dimensional (3D) scene. Autostereograms use only one image to accomplish the effect while normal stereograms require two. The 3D scene in an autostereogram is often unrecognizable until it is viewed properly, unlike typical stereograms. Viewing any kind of stereogram properly may cause the viewer to experience vergence-accommodation conflict.

<span class="mw-page-title-main">Lenticular printing</span> Technology for creating optical illusions

Lenticular printing is a technology in which lenticular lenses are used to produce printed images with an illusion of depth, or the ability to change or move as they are viewed from different angles.

<span class="mw-page-title-main">3D display</span> Display device

A 3D display is a display device capable of conveying depth to the viewer. Many 3D displays are stereoscopic displays, which produce a basic 3D effect by means of stereopsis, but can cause eye strain and visual fatigue. Newer 3D displays such as holographic and light field displays produce a more realistic 3D effect by combining stereopsis and accurate focal length for the displayed content. Newer 3D displays in this manner cause less visual fatigue than classical stereoscopic displays.

<span class="mw-page-title-main">Pseudoscope</span> Binocular optical instrument that reverses depth perception

A pseudoscope is a binocular optical instrument that reverses depth perception. It is used to study human stereoscopic perception. Objects viewed through it appear inside out, for example: a box on a floor would appear as a box-shaped hole in the floor.

<span class="mw-page-title-main">Stereo camera</span>

A stereo camera is a type of camera with two or more lenses with a separate image sensor or film frame for each lens. This allows the camera to simulate human binocular vision, and therefore gives it the ability to capture three-dimensional images, a process known as stereo photography. Stereo cameras may be used for making stereoviews and 3D pictures for movies, or for range imaging. The distance between the lenses in a typical stereo camera is about the distance between one's eyes and is about 6.35 cm, though a longer base line produces more extreme 3-dimensionality.

Random-dot stereogram (RDS) is stereo pair of images of random dots which, when viewed with the aid of a stereoscope, or with the eyes focused on a point in front of or behind the images, produces a sensation of depth, with objects appearing to be in front of or behind the display level.

<span class="mw-page-title-main">Anaglyph 3D</span> Method of representing images in 3D

Anaglyph 3D is the stereoscopic 3D effect achieved by means of encoding each eye's image using filters of different colors, typically red and cyan. Anaglyph 3D images contain two differently filtered colored images, one for each eye. When viewed through the "color-coded" "anaglyph glasses", each of the two images reaches the eye it's intended for, revealing an integrated stereoscopic image. The visual cortex of the brain fuses this into the perception of a three-dimensional scene or composition.

Stereopsis is the component of depth perception retrieved through binocular vision. Stereopsis is not the only contributor to depth perception, but it is a major one. Binocular vision happens because each eye receives a different image because they are in slightly different positions in one's head. These positional differences are referred to as "horizontal disparities" or, more generally, "binocular disparities". Disparities are processed in the visual cortex of the brain to yield depth perception. While binocular disparities are naturally present when viewing a real three-dimensional scene with two eyes, they can also be simulated by artificially presenting two different images separately to each eye using a method called stereoscopy. The perception of depth in such cases is also referred to as "stereoscopic depth".

<span class="mw-page-title-main">Precursors of film</span> Methods and tools preceding true cinematographic technology

Precursors of film are concepts and devices that have much in common with the later art and techniques of cinema.

Underwood & Underwood was a producer and distributor of stereoscopic and other photographic images, and later was a pioneer in the field of news bureau photography.

The Keystone View Company was a major distributor of stereographic images, and was located in Meadville, Pennsylvania. From 1892 through 1963 Keystone produced and distributed both educational and comic/sentimental stereoviews, and stereoscopes. By 1905 it was the world's largest stereographic company. In 1963 Department A and the Education Departments were closed down, but Keystone continued to manufacture eye-training stereographic products as a subsidiary of Mast Development Company. In 1972 Mast closed the Meadville manufacturing site.

<span class="mw-page-title-main">Slide viewer</span> Device for looking at film transparencies

A slide viewer is a device for looking at film transparencies or similar photographic images.

<span class="mw-page-title-main">Benjamin W. Kilburn</span>

Benjamin West Kilburn was an American photographer and stereoscopic view publisher famous for his landscape images of the nascent American and Canadian state, provincial, and national parks and his visual record of the great migrations at the end of the nineteenth century. Kilburn was a legislator in the New Hampshire General Court. A patent was granted for his gun-style camera.

<span class="mw-page-title-main">3D stereo view</span> Enables viewing of objects through any stereo pattern

A 3D stereo view is the viewing of objects through any stereo pattern.

<span class="mw-page-title-main">Stereo photography techniques</span>

Stereo photography techniques are methods to produce stereoscopic images, videos and films. This is done with a variety of equipment including special built stereo cameras, single cameras with or without special attachments, and paired cameras. This involves traditional film cameras as well as, tape and modern digital cameras. A number of specialized techniques are employed to produce different kinds of stereo images.

<span class="mw-page-title-main">Stereoscopic video game</span>

A stereoscopic video game is a video game which uses stereoscopic technologies to create depth perception for the player by any form of stereo display. Such games should not be confused with video games that use 3D game graphics on a mono screen, which give the illusion of depth only by monocular cues but lack binocular depth information.

<span class="mw-page-title-main">Vergence-accommodation conflict</span> Visual and perceptual phenomenon

Vergence-accommodation conflict (VAC), also known as accommodation-vergence conflict, is a visual phenomenon that occurs when the brain receives mismatching cues between vergence and accommodation of the eye. This commonly occurs in virtual reality devices, augmented reality devices, 3D movies, and other types of stereoscopic displays and autostereoscopic displays. The effect can be unpleasant and cause eye strain.

Claude-Marie Ferrier (1811–1889) was an early French photographer, known for his portraits of prominent French people, his work at the London Great Exhibition, and for his production of stereoviews to be viewed through the stereoscope invented by David Brewster.

References

  1. "Register" . The Times . 1856. Retrieved 16 July 2023.
  2. Mayo, Herbert (1833). Outlines of Human Physiology. Burgess and Hill.
  3. Contributions to the Physiology of Vision.—Part the First. On some remarkable, and hitherto unobserved, Phenomena of Binocular Vision. By CHARLES WHEATSTONE, F.R.S., Professor of Experimental Philosophy in King's College, London. Stereoscopy.com
  4. Welling, William 1978. Photography in America, p. 23. 0690014511.
  5. David Sir Brewster (1856). The Stereoscope; its History, Theory, and Construction, with its Application to the fine and useful Arts and to Education: With fifty wood Engravings. John Murray.
  6. Gordon, Margaret Maria (2010). The Home Life of Sir David Brewster. New York: Cambridge University Press. pp. 345–346. ISBN   978-1175699923.
  7. Zone, Ray (2007). Stereoscopic Cinema and the Origins of 3-D Film, 1838–1952 . Lexington: University Press of Kentucky. pp.  9–10. ISBN   978-0813124612.
  8. 1 2 "The Origins of Stereoscopy". Virtual Empire. Sydney University Museums. Retrieved 16 September 2013.
  9. Stafford, Barbara Maria, Frances Terpak and Isotta Poggi (2001). Devices of Wonder: From the World in a Box to Images on a Screen . Los Angeles: Getty Publications. p. 357. ISBN   978-0892365906.{{cite book}}: CS1 maint: multiple names: authors list (link)
  10. "E2 3-D – history of 3-D". Archived from the original on 4 March 2016. Retrieved 6 June 2012.
  11. 1 2 Wing, Paul (1996). Stereoscopes - the first one hundred years. Transition Publishing. pp. 42, 61. ISBN   0-9654497-1-8.
  12. Martiné, Pascal (2 May 2021). "Le Taxiphote - the most famous French stereo viewer".