Who invented lenses and focusing

The lens, which was invented by Dr. Anatoly Snigirev, his wife, Dr. Irina Snigireva, and their colleagues at the European Synchrotron Radiation Facility in Grenoble, France, and at the Kurchatov.. Lens's bend light, and the amount they bend light we call the focal length. With an infinitely distant subject, a lens will focus light at a distance equal to it's focal length. As the subject gets closer, the lens will focus focuses the light behind the infinity focal length, and so to focus we move the lens further away from the film or. The earliest known lenses, called reading stones date from the 11th century and were used by monks to read small print in manuscripts. But as to who invented the concept, nobody knows. 1.6K view Optical theory on refraction and experimentation was showing no single-element lens could bring all colours to a focus. This led to the invention of the compound achromatic lens by Chester Moore Hall in England in 1733, an invention also claimed by fellow Englishman John Dollond in a 1758 patent Optics began with the development of lenses by the ancient Egyptians and Mesopotamians, followed by theories on light and vision developed by ancient Greek philosophers, and the development of geometrical optics in the Greco-Roman world.The word optics is derived from the Greek term τα ὀπτικά meaning appearance, look. Optics was significantly reformed by the developments in the.

In 1267 the English monk and scientist Roger Bacon (c. 1214-1294) wrote about his experiments in using convex lenses to correct vision, advocating their use to help old people. Convex spectacles seem to have been invented around 1285 Salvino D'Armate probably invented eyeglasses in around 1285, though various sources suggest an earlier origin. He shared the invention of his new device with Allesandro della Spina, an Italian monk, who made it public and is often credited with inventing eyeglasses. The first eyeglasses had frames made of metal or bone and had lenses made out. 'The first mass-produced autofocus camera was the Konica C35 AF, a simple point and shoot model released in 1977. The Polaroid SX-70 was the first autofocus single-lens reflex camera, released in 1978. The Pentax ME-F, which used focus sensors in the camera body coupled with a motorized lens, became the first autofocus 35mm SLR in 1981 Variable Focus Technology is the way the Adlens eyewear, John Lennon, Hemisphere and Emergensee work. It makes it possible to change eyeglass lens power by self-adjustment. That's right; minus and/or plus lens power in these glasses is not fixed, until the wearer chooses it In 1840, Chevalier developed the world's first variable focus lens, specifically for portraiture. This lens sported an aperture of f/6, requiring shorter exposure times. This design was shared among the newly born photographic community and Max Petzval developed an even better portrait lens, also in 1840. This lens was made by Voigtlander

Physicists Invent Lens for Focusing X-Rays - The New York

A Brief History of Focusing • Points in Focus Photograph

The invention of the first contact lens, essentially as we know it today, was done by a glass blower and artificial eye maker, F. E. Muller of Wiesbaden in Germany in 1887. Muller was so highly respected for his invention that he was made an honorary Doctor of Medicine The correct answer is the microscope, it was invented at the end of the 16th Century. Subsequently an Englishman, Hooke, developed a compound microscope using two convex lenses (objective lens and ocular), and in almost the same period, a single lens microscope was first developed in the Netherlands

A relative newcomer to the interchangeable-lens camera arena, Samsung's lenses have focusing rings that turn past infinity and only one of their current line, the Samsung 85 f/1.4 ED SSA, features focusing marks on the lens. Their owner's manuals state that the zoom lenses are not parfocal and need focus adjustments after zooming in or out Leica invented the autofocus camera system with the Correfot in 1976. Legendary German camera maker Leica spent nearly 20 years patenting technology that would take focusing out of the hands of. The engineer Bernard Maitenaz invented progressive lenses in 1959. He joined SL in 1948. Bernard Maitenanz patented a lens design with progressively increasing lens powers in the lower half of the lens. The picture shows Bernard Maitenaz the inventor of progressive lenses

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Who invented optical lens? - Quor

These lenses, followed later by the Hypergon, provided fields of view to 75 degrees (about 28mm) at apertures around f/20. Short Focus Lenses. The revolution in lens design that occurred from 1890 to 1905 allowed lens designers to develop much better wide-angle lenses The story of the contact lens begins with one of the most famous inventors of all time. In 1508, Leonardo da Vinci wrote the 'Codex of the Eye'. In his manuscript, Leonardo considered the possibility that submerging one's head in a glass bowl of water could correct certain vision ailments! Remarkably, da Vinci went on to create a glass.

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Lens - Wikipedi

Chester Moor Hall who was the original inventor, commissioned 2 opticians James Mann and Edward Scarlet in 1733 each to make one lens element. Coincidentally both opticians subcontracted the work to George Bass. At around 1750, George Bass discovered that different glasses had different dispersing power and invented an achromatic lens Re: who invented Auto-Focus? In reply to Brian Aitkenhead • Oct 28, 2007. 1. 'The first mass-produced autofocus camera was the Konica C35 AF, a simple point and shoot model released in 1977. The Polaroid SX-70 was the first autofocus single-lens reflex camera, released in 1978. The Pentax ME-F, which used focus sensors in the camera body. This 73% water lens was a fairly short-lived product that soon ceased production. Each box contained 3 blister packs. Daily disposable lenses. Daily disposable lenses, for use just once before throwing away, were made available in 1995. The first was the Premier Award lens invented by Ron Hamilton in Scotland

Below is a brief history of the microscope, including who invented the microscope. During the 1st century AD (year 100), glass had been invented and the Romans were looking through the glass and testing it. They experimented with different shapes of clear glass and one of their samples was thick in the middle and thin on the edges The World's First Soft Contact Lens. In 1961, Czechoslovakian chemists made the world's first soft contact lens using a water-absorbing, soft plastic material, that they had invented, called HEMA. This work later led to the first commercial introduction of soft contact lenses by Bausch & Lomb. The year was 1971 1948 - The first hard lenses were produced by Kevin Tuohy. 1959 - Wichterle and Lim, chemists from Czechoslovakia, invented the first soft contact lens made of hydrogel. 1971 - Bausch and Lomb launch the first FDA-approved soft contact lens in the US. 1979 - RGP lenses introduced. 1981 - Extended wear soft lenses introduced

The word microscope is a combination of two Greek words, mikros, or small, and skopos, or watcher. So a microscope is a watcher of the small! It is an instrument used to see tiny things which are invisible to the naked eye. Normally an objec.. The artificial lens would take over the job of focusing light onto the retina, improving vision in numerous ways without glasses, but in a flexible, interactive way. Madison, have invented a. Someone also discovered that you can focus the rays of the sun with one of these special glasses and start a fire. These early lenses were called magnifiers or burning glasses. The word lens by the way, is derived from the latin word lentil, as they were named because they resembled the shape of a lentil bean (look up lens in a dictionary) The lens was known, the camera was known, and the reaction of silver salts when exposed to light had been known for a hundred years. What made it new was that everything was brought together, while the problem of making the silver salts sufficiently sensitive to light was solved, and a method was found of fixing the pictures so that they did. From their origins as reading stones to lifestyle accessories. According to experts, glasses are the fifth most important invention since mankind discovered fire and invented the wheel. The reason: for the first time in human history, millions of people were able to enjoy good vision in spite of problems with their vision

Revised 6 April 2021. Telescopes are instruments which use multiple lenses to produce magnified images of distant objects. It is unclear who invented the first telescope: lenses had been widely used in Europe to correct poor eyesight since the fourteenth century and I expect that, over time, the telescope was actually invented many times by different individuals, who discovered that combining. Objects resembling lenses date back 4000 years although it is unknown if they were used for their optical properties or just as decoration. Greek accounts of the optical properties of water filled spheres (5th century BC) followed by many centuries of writings on optics, including Ptolemy (2nd century) in his Optics, who wrote about the properties of light including reflection, refraction, and.

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This lens was invented in 1925 by Dr. Albrecht Wilhelm Tronnier (1902-1982) while he was working for Jos. A. Schneider Optical Works in Bad Kreuznach, Germany, known as Schneider-Kreuznach. And while it is less heralded compared with more popular designs, the Xenon's history and performance are worth a look (and a shoot) In 1590, together with his father, he succeeded in creating a microscope using convex and concave lenses to enlarge the appearance of objects of very small size. The first focusing tuning mechanism for the microscope was made and refined by Campini, an Italian scientist, in 1668

In 1975, Steven Sasson invented the world's first digital camera while working at Eastman Kodak. It weighed around 3.6k Kg and shot 0.01MP. It is said that the first ever photograph taken on his digital camera was of a lab technician called Joy in December 1975. However, the image wasn't saved Monthly Disposable Contact Lenses. Air Optix Aqua 2, Air Optix Night & Day Aqua , Biofinity 2 , Clarity H2O, Focus Monthly Visitint 2, Focus Night & Day 2, Frequency 55 2, Frequency 55 Aspheric 2, Optima 38 SP 2, Preference 2, Preference Standard 2, Proclear Compatibles 2, PureVision 2

The two lenses are normally connected by a tube; the object to be examined is placed under the objective lens and brought into focus by adjusting the distance to the object. The Janssens, due to their occupation, would have been familiar with the manufacture and properties of lenses, and it is thought that the first compound microscope may have. A convex lens that can bend and focus light. The key for a microscope to magnify the image is the convex lens. The oldest objects resembling lenses can date back 3,000 years. This Nimrud lens is a crystal disk with a convex shape that belonged to an ancient Near East empire, Assyria

When was the lens invented? 1887. Who invented lenses for glasses? friar Roger Bacon. Who invented convex lens? Roger Bacon. How was the first lens made? Between the 11th and 13th century reading stones were invented. These were primitive plano-convex lenses initially made by cutting a glass sphere in half They discovered that multiple glass lenses created greater magnification than single lens. The famous scientist and inventor Galileo heard about their experiments and started work on this own. He added a focusing mechanism to the microscope and it was given the name of microscope in 1625 from Giovanni Faber Many people believe that Galileo Galilei was the first astronomer to invent and build the telescope; however, the first telescope was made by Hans Lippershey in the early 1600s. Lipperhey was a German-Dutch glass maker, and he managed to reduce the amount of light in his telescope while focusing it

History of optics - Wikipedi

at focus online, we know guys look great in polarised sunglasses , and guys like to show off a quality pair of glasses that are hot for him when he's outside in the sun. Sex appeal is an important component of men's eyewear, because it reveals something about the character of the guy who's wearing a particular pair of lenses, a particular. The Early 1880s - Dr Adolf Fick Invented Refractive Power Contact Lens. The evolution of clear contact lens was making good progress starting in the early 1880s. Dr Adolf Fick together with his other colleagues managed to invent the first contact lens with refractive power to improve eyesight Bifocals in the animal world. The aquatic larval stage of the diving beetle Thermonectus marmoratus has, in its principal eyes, two retinas and two distinct focal planes that are substantially separated (in the manner of bifocals) to switch their vision from up-close to distance, for easy and efficient capture of their prey, mostly mosquito larvae. This is the first ever recorded use of. Over 90% of the contact lenses on the market today are soft contact lenses. Due to their ease of handling and disposable convenience, these lens are perfect for those who no longer want to wear glasses. The first commercially available bifocal contact lenses (daily wear) were introduced in 1982 and the disposable versions in 1999

Download this stock image: . The microscope; an introduction to microscopic methods and to histology. Microscopes. Ch. xu] history of lenses and microscopes 429 their easier handling or focusing. The common reading glass with its convenient handle (fig. 4) and the tripod (fig. 201) and focusing lens holder (fig. 202) are good examples. In reading the older hterature one often meets with the. The physics of lens construction was examined by German physicist Ernst Abbe. In 1868 he invented an apochromatic system of lenses, which had even better colour correction than achromatic lenses, and in 1873 he published a comprehensive analysis of lens theory. Light microscopes that were produced in the closing quarter of the 19th century. When it comes to autofocusing manual lenses on film cameras there is really only one option: the unique and relatively short-lived CONTAX AX. Chunky sibling of the CONTAX RX and RTS cameras, the AX was released in 1996 and it remains the only camera ever produced that can autofocus manual focus lenses.. The AX was produced by Kyocera who took indirect stewardship of the CONTAX brand following. The metallurgical microscope was invented in 1863 by a geologist named Henty Clifton Sorby, who, among other things, also founded metallography, which is the study of metal's physical components and physical structure through microscopy. Sorby made several important discoveries in different sciences; however, his most significant was the discovery of methods to analyze metals and.

Who invented lensometer? In 1921 The 'AO Lensometer' was patented by the 40-year old Edgar Derry Tillyer on behalf of the American Optical Company. Somewhat debatably this was claimed to be the first instrument to allow measurement of the effective power of a lens and thus check the accuracy of prescriptions. Click to see full answer A Galilean telescope is a very simple construction consisting of only one concave lens and one convex lens. The convex lens serves as an objective, the concave lens serves as an eyepiece. The lenses are located on opposite sides of a tube so that the focal point of the objective lens coincides with the focal point of the ocular lens. Johannes.

Who invented contact lenses? The first sketches of the concept of contact lenses came from none other than Leonardo da Vinci in 1508. It wasn't until 1888 when Adolf Fick, a German ophthalmologist, successfully built and fitted the first pair of glass contact lenses. In 1959, Czech chemists Drahoslav Lim and Otto Wichterle introduced soft. Galileo immediately began to work with lenses. In a short timeframe, he developed an improved telescope with a focusing device and went on to conquer the stars. That said, we should also pay tribute to Sir Isaac Newton who around the same time in the UK, invented the reflecting telescope. Compound Microscope History of Eyewear: How Glasses, Sunglasses, and Goggles Came to Be. Bob Smith (right) developed the first sealed thermal lens and breathable vent foam goggles in 1965, revolutionizing performance eyewear and kicking off more than half a century of innovation at Smith Optics. Believe it or not, eyewear—namely eyeglasses—have had a long.

The Invention of Spectacles Encyclopedia

  1. First of all, the focal length of a lens (you know that 50mm lens you own) is the distance at which an object that is an infinite distance away will focus to on the other side of the lens. Take a picture of the moon and you can be sure that very close to 50mm behind your lens, inside your camera, there is a sharp virtual image of the moon
  2. Multifocus Lens. A multiple focus intraocular lens gives focus to more than one of the important areas of vision. If want your eyes do the focusing rather than glasses then a multifocus may be right for you. Around 80% of those with a multifocus lens implant never wear glasses again and around 94% don't need reading glasses
  3. imum focusing distance of 12 inches or less. It's optimized to handle focusing at extremely close distances and produces highly detailed images of tiny subjects
  4. The largest refracting telescope (one that use lenses to gather and focus light) opened at Yerkes Observatory in Williams Bay, Wisconsin, in 1897. But the 40-inch (1 meter) glass lens at Yerkes was soon made obsolete by larger mirrors. The Hooker 100-inch (2.5 m) reflecting telescope opened in 1917 at Mount Wilson Observatory in Pasadena, Calif
  5. In reflex cameras (both twin-lens and single-lens reflex), a mirror is used to reflect the light from a lens onto a horizontal ground-glass focusing screen at the top of the camera. The only difference between SLR and TLR arrangements is that in the SLR camera, the mirror is moved immediately before exposure, to allow the light to be focussed onto the film, plate or sensor instead, while in a.
  6. The World's First Soft Contact Lens. In 1961, Czechoslovakian chemists made the world's first soft contact lens using a water-absorbing, soft plastic material, that they had invented, called HEMA. This work later led to the first commercial introduction of soft contact lenses by Bausch & Lomb. The year was 1971

Who Invented Eyeglasses? - Who was Glasses Inventor

The lens is used to make focusing adjustments. Who invented the microscope? How did it get invented? The microscope is one of the most important discoveries through the history, because of the improved understanding about the human body, it gave. About 2000 years ago, the Romans had made magnifying glasses out of rock crystals, but they were. The position of the two plates determines the power of the lens system. VisionPro glasses are designed to replace all your spare and reading glasses. The power of the lenses can be customized instantly to correct from -6 diopters of nearsightedness to +3 of farsightedness with the simple turn of a dial

Contact lenses and acanthamoeba keratitis infection. Acanthamoeba keratitis is a severe but very rare painful infection of the cornea, the transparent outer covering of the eye, which usually causes scarring and, if undiagnosed and untreated, can lead to blindness. In the most severe cases, a corneal transplant is necessary Objective lenses - A standard microscope has three or even four objective lenses. Each lens features different powers starting from x4 all the way to 10x, 40x and 100x. When coupled with the most common eyepiece lens which is the most common power lens, you get a total of up to 40x magnification. This is of course, not the best magnification The objective lenses which are made up of six or more glass lenses, which make a clear image clear from the specimen or the object that is being focused. Two focusing knobs i.e the fine adjustment knob and the coarse adjustment knob, found on the microscopes' arm, which can move the stage or the nosepiece to focus on the image 2. Set the lens to MF (Manual Focusing). Be careful not to jostle the focus ring when you move the switch - you don't want to alter the focus you established in step #1. Then just reverse the steps. You don't need to have the lens in AF mode to perform what you're doing in your step 1. Feb 03, 2013 at 05:05 P

who invented Auto-Focus?: Open Talk Forum: Digital

Lenses in this group are the Kodak Single Meniscus and Doublet Lenses, and the Kodet, a single meniscus type lens. The Kodak Diway was a single fixed element lens having a second element (or closeup diopter) that could swing in front of the main lens for close focusing. In the 1950s, Kodak began making simple lenses from acrylic plastics Multifocal and bifocal contact lenses are designed for people with presbyopia who have trouble focusing on close-up objects. They work by combining correction for distance and near vision into the same contact lens. Multifocal lenses have improved significantly in recent years due to better technology. If you've thought about ditching your reading glasses in favor [ Before phacoemulsification was developed, surgeons would remove the entire lens and capsule. This made it difficult to insert an intraocular lens. The lens of the eye contributes a lot of focusing power to the eye. As a result, if you remove the cataract, which is the lens, the patient is left with a very high plus, farsighted prescription February 18, 2016. Along with the introduction of the Canon EOS 80D camera, Canon engineers are introducing an updated version of the popular EF-S 18-135mm f/3.5-5.6 IS lens. The headline feature of this lens is a completely new type of Ultrasonic motor technology, called Nano USM. We'll concentrate on the Nano USM in this article, but.

Variable Focus Technology - Adlen

  1. Lenses, like mirrors, suffer from spherical aberration, which causes light-rays parallel to the optic axis, but a relatively long way from the axis, to be brought to a focus, or a virtual focus, closer to the lens than light-rays which are relatively close to the axis. It turns out that spherical aberration in lenses can be completely cured by using lenses whose bounding surfaces are non.
  2. The single-lens reflex camera (Figure 2) has a screen, but the film remains constantly in Read More; viewfinder mechanism. In viewfinder. In the single-lens reflex camera, the camera lens itself serves as the finder in conjunction with a ground-glass focusing screen to which the image is reflected by a mirror
  3. Then in 1822 a French Physicist named Augustine Fresnel invented a lens that would make his name commonplace along the coasts of Europe and North America. A fresnel lens looks like a giant glass beehive, with a light at the center. Enhanced focusing screens - another use of Fresnel lenses; Overhead.
  4. Refraction is how lenses in eye glasses, telescopes and binoculars work. In eye glasses, the lenses bend light enough to focus the image for the wearer to see clearly. 5. The telescope is one of humankind's most important inventions. We've been using them since 1608 when a Dutch eyeglass maker, Hans Lippershey, is said to have invented them. 6
  5. In the 1880's, George Eastman started a company called Kodak. He created small box camera with no focusing adjustments and a single lens. It consisted of a roll of film that he could take back and develop 100 exposures from in a dark room. This meant the general public could purchase them, take their images, then return to the store to be.
  6. The Panavision Story In 1954, Robert Gottschalk and his partners saw an opportunity to solve one of the film industry's most urgent challenges. The special lenses necessary to project CinemaScope and other wide-screen films were expensive, difficult to use, and in short supply. The Panavision Super Panatar® - the Gottschalk Lens - featured a variable prism tha
  7. By Robert Matthews. In 1992, a telescope built by the British astronomer and historian Colin Ronan was shown on The Sky At Night. Telescopes have been vital to science since Dutch spectacle maker Hans Lippershey patented the now-familiar arrangement of lenses in 1608. But what made Ronan's telescope different was that it was built to a design.

A Brief History of the Photographic Lens Will Moneymaker

What compound (multiple-lens) microscopes in the late 1660's could have served as models for Leeuwenhoek? The style of microscope that Galileo used had a lens at each end of a tube and one in the middle. The style of microscope that Robert Hooke used had a lens at each end of the tube. It also had a removable lens in the middle of the tube These Are the Downsides of Focus Peaking. Of course, focus peaking isn't foolproof. One of its main weaknesses can be seen most readily when using a lens stopped down or when using a wide angle lens; either scenario presents a situation in which there is a lot of depth of field present and can lead to focus peaking highlighting the whole scene The invention of the movie camera is, ironically, a story worthy of Hollywood. In 1888, the renowned American inventor Thomas Edison drew up plans to build a camera which could record moving images onto a cylinder. Within a few years, colleagues had produced a more sophisticated device that captured images onto a reel of 35mm photographic film. 2007 Schools Wikipedia Selection.Related subjects: Engineering; General Physics The optical microscope is a type of microscope which uses visible light and a system of lenses to magnify images of small samples. Optical microscopes are the oldest, simplest and. Optical configurations. There are two basic configurations of optical microscope in use, the simple (one lens) and compound (many lenses) In 1971, soft contact lens officially hit America. Soft plastic lenses are more flexible and easy to wear. They also absorb water, which helps them to increase oxygen flow to the eyes. In 1982, a man from Denmark invented disposable lenses. The next breakthrough didn't come until 1995, when daily disposable contact lenses made it onto the market

Breakthrough Discovery Leads to Invention of neurolenses

The most direct descendant of the Franklin lens is the Flat-top bifocal. These lenses have a very large area devoted to your distance vision, with a smallish insert or segment that allows you to focus on objects up close. The working distance, how far away you can hold something and still be in focus, is fixed with this type of bifocal An aperture stop on the concave side of the lens blocks the mis-focusing incoming light rays, creating sharper, more detailed images with progressively smaller openings. Invented by William Wollaston (England, ca. 1804-1812) this meniscus lens arrangement has been used in millions of simple cameras dating back to the original 1888 box-shaped. A lens invented at The Ohio State University combines the focusing ability of a human eye with the wide-angle view of an insect eye to capture images with depth. The results could be smartphones.

The history of the len

Full answer is here.Besides, who first invented the microscope? Zacharias Janssen . Also, what was the first microscope used for? First Microscope Grinding glass to use for spectacles and magnifying glasses was commonplace during the 13th century. In the late 16th century several Dutch lens makers designed devices that magnified objects, but in 1609 Galileo Galilei perfected the first device. Later in his career, during the 1950s, Walker revived his interest in zoom lens technology. He adapted the zoom lens he had developed during the 1920s. Renamed the 'Electra-Zoom', the new product featured a motor which enabled the operator to zoom in or out smoothly. As American Cinematographer reported in May 1950: The beauty of the end.

The Barlow lens was invented by Peter Barlow (1776-1862) an English writer on pure and applied mathematics. A Barlow lens is a concave lens that when placed between a telescopes objective lens or mirror and the eyepiece, will increase the magnification of the telescope. A Barlow lens will connect directly to your eyepiece The liquid lens, a revolutionary optical device invented and patented by French physicist-turned-entrepreneur Bruno Berge, is shaking up the market for optical instruments. This innovative lens enables better, cheaper and smaller optical devices and is already used in a wide range of products, including ID readers (such as barcode or passport.

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The lens is said to be able to focus sunlight although the focus is far from perfect. There has been much debate over the original use of the Nimrud lens. Some speculate that it was used as a magnifying glass, or as a burning-glass to start fires by concentrating sunlight, while others have proposed that the lens was part of a telescope Concave lenses: Thick at the perimeter and thin at the center, the concave shape moved the eye's focus back toward the retina screen to correct nearsightedness (myopia). Convex lenses: Like a magnifying glass, these lenses are thickest at the center, moving the eye's focus forward from behind the retina to correct farsightedness (hyperopia) Who invented soft contact lenses: contact lenses eye care sickle cell, tinted contact lenses, contact lenses roswell georgia, acuvue contact lenses for 202f20 vision. And when it does conta ct up, I exercise my duty to blast, bash and some drug-free ways to ease the pain hopes that someday in someplace I might help out a poor soul that is At the Susan G A Critical Literary Lens influences how you look at a work. A great example that is often used, is the idea of putting on a pair of glasses, and the glasses affecting how you view your surroundings. The lens you choose is essentially a new way to focus on the work and is a great tool for analyzing works from different viewpoints