Although Fresnel, who had also the satisfaction of being the first to put it into operation, perfected the dioptric apparatus independently, Brewster was active earlier in the field than Fresnel, describing the dioptric apparatus in 1812.

Although the aether is almost stationary according to Fresnel, his theory predicts a positive outcome of aether drift experiments only to second order in, because Fresnel's dragging coefficient would cause a negative outcome of all optical experiments capable of measuring effects to first order in.

Although older technology required the user to don goggles or visors for viewing computer-generated images, or CGI, newer technology tends to employ Fresnel lenses or plates over the liquid crystal displays, freeing the user from the need to put on special glasses or goggles.

Although a lens can precisely focus at only one distance at a time, the decrease in sharpness is gradual on each side of the focused distance, so that within the DOF, the unsharpness is imperceptible under normal viewing conditions.

Although a Dutch spectacle maker created the compound lens and inserted it in a microscope around the turn of the seventeenth century, and Galileo had applied the principle of the compound lens to the making of his microscope patented in 1609, its possibilities as a microscope had remained unexploited for half a century, until Robert Hooke improved the instrument.

Although named after Dutch astronomer Willebrord Snellius ( 1580 – 1626 ), the law was first accurately described by the Arab scientist Ibn Sahl at Baghdad court, when in 984 he used the law to derive lens shapes that focus light with no geometric aberrations in the manuscript On Burning Mirrors and Lenses ( 984 ).

Although all the above lens types — sclerals, PMMA lenses and RGPs — could be correctly referred to as being " hard " or " rigid ", the term hard is now used to refer to the original PMMA lenses, which are still occasionally fitted and worn, whereas rigid is a generic term that can be used for all these lens types: hard lenses ( PMMA lenses ) are a sub-set of rigid lenses.

Although the lens does not restore normal color vision, it allows some colorblind individuals to distinguish colors better.

Although many brands of contact lenses are lightly tinted to make them easier to handle, cosmetic lenses worn to change the color of the eye are far less common, accounting for only 3 % of contact lens fits in 2004.

Although the materials are the same, the manufacturing processes by which the respective contact lenses are made is what differentiates a " daily disposable " lens from a lens recommended for two-week or 4-week replacement.

Although they have less flexibility than monorail cameras, modern field cameras tend to have most camera movements for the front standard, i. e. lens rise / fall / shift / tilt / swing, but are usually more limited in back movements, sometimes having only tilt / swing.

Although many cameras of the mid nineteenth century were wooden and " boxy " in appearance with a brass fitted lens on the front they should not be confused with the mass produced box cameras that exploded in popularity after the introduction of the first Kodak.

Although the lenses appear similar in layout, there is a lot more to the design and performance of a lens than simply the layout of the glass elements.

Although this means that it is not possible to focus the beams nearly as tightly as for light, it also means that the aperture or " capture area " of even the simplest, omni-directional antenna is greatly larger than that of a lens in any feasible optical system.

Although the camera was capable of ' capturing ' motion, it wasn't a complete success because each lens photographed the subject from a slightly different viewpoint and thus the projected image jumped about.

Although the optical format size bears no relationship to any physical parameter of the sensor, its use means that a lens that would have been used with ( say ) a four thirds inch camera tube will give roughly the same angle of view when used with a solid state sensor with an optical format of four thirds inch.

Although Frazier reshot the footage in question with the FrazierPanavision lens the patent was declared unenforceable for inequitable conduct and attorney's fees were awarded to the defendants.

Although the Nikon F3AF ( 1983 ), Pentax ME F and Chinon CE-5 already had presented autofocus single lens reflex cameras, autofocusing could not be achieved without the use of special motorised AF lenses.

Although eye-cups can usually be folded down to allow the spectacle wearer to get closer to binocular eyepieces, there are sometimes lens mountings that do not allow the theoretical eye relief to be obtained.

Although slower, this lens introduced improvements such as optical image stabilisation, a higher zoom range ( 6 ×), and a macro mode that would focus as close as 1 cm.

Although there is no clear beginning or end of a microlensing event, by convention the event is said to last while the angular separation between the source and lens is less than.

Although distortion can be irregular or follow many patterns, the most commonly encountered distortions are radially symmetric, or approximately so, arising from the symmetry of a photographic lens.

Although Night Man has no other superhuman powers on his own, he owns a special bulletproof bodysuit that gives him several abilities, including flight, holographic camouflage-style invisibility and advanced sight functions through the round red lens over his left eye including the ability to see in the dark and fire a laser beam.

Although it was dark as usual I could see that the hall had only recently contained a great many people.

Although New Orleans was not to learn of it for a spell, she also was a sadist, a nymphomaniac and unobtrusively mad -- the perpetrator of some of the worst crimes against humanity ever committed on American soil.

Although Faulkner was the heir in his own family to this tradition, he did not have Stark Young's inclination to romanticize and sentimentalize the planter society.

Although his tender nights were not the ones I dreamed of, nor was it for yachts, sports cars, tall drinks, and swimming pools, nor yet for money or what money buys that I burned, I too was burning and watching myself burn.

Although after much trouble he did manage to get it back, he discovered there was no trade to be had.

Although he did not attend any celebrated schools or universities, he was a master of Greek and Hebrew and could read the Bible in the original.

Although the fort was evacuated in the face of the force of Cornwallis, Morgan and his men did have a chance to take another swing at the redcoats.

Although because of the important achievements of nineteenth century scholars in the field of textual criticism the advance is not so striking as it was in the case of archaeology and place-names, the editorial principles laid down by Stevenson in his great edition of Asser and in his Crawford Charters were a distinct improvement upon those of his predecessors and remain unimproved upon today.

Although Mr. Brown was not himself its inventor ( it was a French idea ), it is typical that his intuition first conceived the importance of mass producing this basic tool for general use.

Although it was a mere fragment of the victim's remains, it was enough.

Although there were only four fluids tested, it was apparent that there were two distinct types.

Although the tape was run for over 1 hr., a steady state was not reached, and it was concluded that the reason for this was that the back pressure of the manometer was built up from the material fed from between the blocks and this was available at a very slow rate.

-- Although there was some variation in results which must be attributed either to trace impurities or to variation in wall effects, the photochemical exchange in the gas phase was sufficiently reproducible so that it seemed meaningful to compare the reaction rates in different series of reaction tubes for the purpose of obtaining information on the effect of chlorine concentration and of carbon tetrachloride concentration on the reaction rate.

Although the Taylor Scale was designed as a group testing device, in this study it was individually administered by psychologically trained workers who established rapport and assisted the children in reading the items.

Although these encryption methods were more complex than previous schemes and required machines to encrypt and decrypt, other machines such as the British Bombe were invented to crack these encryption methods.

Although Confucius claimed that he never invented anything but was only transmitting ancient knowledge ( see Analects VII, 1 ), he did produce a number of new ideas.

Although the names are old, this opposition is a modern western-influenced development popularized by Martin Haug in the 1880s, and was in effect a realignment of the precepts of Zurvanism ( Zurvanite Zoroastrianism ), which had invented a third deity, Zurvan, in order to explain a mention of twinship ( Yasna 30. 3 ) between the moral and immoral.

Although largely residential, Hayling is also a holiday, windsurfing and sailing centre, the site where windsurfing was invented.

Although the milling machine was invented at this time, it was not developed as a serious workshop tool until somewhat later in the 19th century.

Although Jack Worrall claimed that he had invented the term " bodyline ", it is more likely that it was coined by Sydney journalist Hugh Buggy who worked for The Sun in 1932, and who happened to be a colleague of Jack Fingleton.

Although Confucius claimed that he never invented anything but was only transmitting ancient knowledge ( see Analects VII, 1 ), he did produce a number of new ideas.

Although Miller claims he invented the words " epismetology " ( metathesis of epistemology ) and " pompatus ", all of his song-writing demonstrates strong rhythm and blues influences, and a 1954 song called " The Letter " by the Medallions had the lines:

Although the Chinese invented gunpowder, and firearms had been in continual use in Chinese warfare since as far back as the Song Dynasty, the advent of modern weaponry resulting from the European Industrial Revolution had rendered China's traditionally trained and equipped army and navy obsolete.

Although many consider it a solved problem, useful new sorting algorithms are still being invented ( for example, library sort was first published in 2006 ).

Although Franciscus Vieta ( 1540 – 1603 ) gave the first notation of modern algebra, John Napier ( 1550 – 1617 ) invented logarithms, and Edmund Gunter ( 1581 – 1626 ) created the logarithmic scales ( lines, or rules ) upon which slide rules are based.

Although this was interpreted by later writers, Pliny and Diodorus, to mean that triremes were invented in Corinth, it is likely that the earliest three-tiered warships originated in Phoenicia.

Although the paper ran the editorial in the seventh place on the page, below even one on the newly invented " chainless bicycle ", its message was very moving to many people who read it.

Although Ashley seemed to imply that he had invented the constrictor knot over 25 years before publishing The Ashley Book of Knots, research indicates that he was not its originator.

Although certainly not invented by him this variant of the sheepshank knot appeared in an episode of the TV show Man Vs Wild.

Although sources assert that the device was invented in the late 18th century, other accounts recognise that similar ' decapitation machines ' have a long history.

Although the Elvish languages Sindarin and Quenya are the most famous and the most developed of the languages that Tolkien invented for his Secondary World, they are by no means the only ones.

Although the technology of printing text using movable type was invented in China, and despite the esteem which calligraphy held in that civilization, the vast number of Chinese characters meant that few distinctive, complete fonts could be afforded by Chinese printers.

Although there have been claims that Salvino D ' Armate of Florence invented eyeglasses, these claims have been exposed as hoaxes.

Although Earhart and Putnam had no children, he had two sons by his previous marriage to Dorothy Binney ( 1888 – 1982 ), a chemical heiress whose father's company, Binney & Smith, invented Crayola crayons: the explorer and writer David Binney Putnam ( 1913 – 1992 ) and George Palmer Putnam, Jr. ( born 1921 ).

Although Belgian gastronomy is connected to French cuisine, some recipes were reputedly invented there as e. g. French-fried potatoes ( despite the name ), stoofkarbonnaden ( or carbonade flamande in French, a beef stew with beer, mustard and bay laurel ), speculaas ( a sort of cinnamon and ginger-flavoured cookie ), Brussels waffles ( and their variant, Belgian waffles ), waterzooi ( a broth made with chicken or fish, cream and vegetables ), endive with bechamel sauce, Brussels sprouts, Belgian pralines ( Belgium has some of the most renowned chocolate houses ), charcuterie ( deli meats ) and Paling in't groen ( river eels in a sauce of green herbs ).

Although Alberti is usually considered the father of polyalphabetic cipher, it has been claimed that polyalphabetic ciphers may have been developed by the Arab cryptologist Al Kindi 600 years before Alberti. Johannes Trithemius, in a book published after his death, invented a progressive key polyalphabetic cipher called the Trithemius cipher.

Although there have been claims that Nellie Bly invented the barrel, the inventor is believed to have been Henry Wehrhahn, who likely assigned his invention to her.

Although other internal combustion engines had been invented, these were not based on four separate strokes.