Gill Sans is a sans-seriftypeface designed by Eric Gill and released by the British branch of Monotype from 1928 onwards.
Gill Sans is based on Edward Johnston's 1916 "Underground Alphabet", the corporate font of London Underground. Gill as a young artist had assisted Johnston in its early development stages. In 1926, Douglas Cleverdon, a young printer-publisher, opened a bookshop in Bristol, and Gill painted a fascia for the shop for him in sans-serif capitals.[a] In addition, Gill sketched an alphabet for Cleverdon as a guide for him to use for future notices and announcements. By this time Gill had become a prominent stonemason, artist and creator of lettering in his own right and had begun to work on creating typeface designs.
Gill was commissioned to develop his alphabet into a full metal type family by his friend Stanley Morison, an influential Monotype executive and historian of printing. Morison hoped that it could be Monotype's competitor to a wave of German sans-serif families in a new "geometric" style, which included Erbar, Futura and Kabel, all being launched to considerable attention in Germany during the late 1920s. Gill Sans was released in 1928 by Monotype, initially as a set of titling capitals that was quickly followed by a lower-case. Gill's aim was to blend the influences of Johnston, classic serif typefaces and Roman inscriptions to create a design that looked both cleanly modern and classical at the same time.
Marketed by Monotype as a design of "classic simplicity and real beauty", it was intended as a display typeface that could be used for posters and advertisements, as well as for the text of documents that need to be clearly legible at small sizes or from a distance, such as book blurbs, timetables and price lists. Designed before setting documents entirely in sans-serif text was common, its standard weight is noticeably bolder than most modern body text fonts.
An immediate success, the year after its release the London and North Eastern Railway chose it for all its posters, timetables and publicity material. British Railways chose Gill Sans as the basis for its standard lettering when the railway companies were nationalised in 1948. Gill Sans also soon became used on the modernist, deliberately simple covers of Penguin books, and was sold up to very large sizes which were often used in British posters and notices of the period. Gill Sans was one of the dominant typefaces in British printing in the years following its release, and remains extremely popular: it has been described as "the British Helvetica" because of its lasting popularity in British design. Gill Sans has influenced many other typefaces, and helped to define a genre of sans-serif, known as the humanist style.
Monotype rapidly expanded the original regular or medium weight into a large family of styles, which it continues to sell. A basic set is included with some Microsoft software and macOS.
The proportions of Gill Sans stem from monumental Roman capitals in the upper case, and traditional "old-style" serif letters in the lower. This gives Gill Sans a very different style of design to geometric sans-serifs like Futura, based on simple squares and circles, or realist or grotesque designs like Akzidenz-Grotesk, Helvetica and Univers influenced by nineteenth-century lettering styles. For example, compared to realist sans-serifs the "C" and "a" have a much less "folded up" structure, with wider apertures. The "a" and "g" in the roman or regular style are "double-storey" designs, rather than the "single-storey" forms used in handwriting and blackletter often found in grotesque and especially geometric sans-serifs.
The upper-case of Gill Sans is partly modelled on Roman capitals like those found on the Column of Trajan, with considerable variation in width. Edward Johnston had written that, "The Roman capitals have held the supreme place among letters for readableness and beauty. They are the best forms for the grandest and most important inscriptions." While Gill Sans is not based on purely geometric principles to the extent of the geometric sans-serifs that had preceded it, some aspects of Gill Sans do have a geometric feel.[b] The "O" is an almost perfect circle and the capital "M" is based on the proportions of a square with the middle strokes meeting at the centre; this was not inspired by Roman carving but is very similar to Johnston.[c] The 'E' and 'F' are also relatively narrow.
The influence of traditional serif letters is also clear in the "two-storey" lower-case "a" and "g", unlike that of Futura, and the "t" with its curve to bottom right and slanting cut at top left, unlike Futura's which is simply formed from two straight lines. The lower-case "a" also narrows strikingly towards the top of its loop, a common feature of serif designs but rarer in sans-serifs.
Following the traditional serif model the italic has different letterforms from the roman, where many sans-serifs simply slant the letters in what is called an oblique style. This is clearest in the "a", which becomes a "single storey" design similar to handwriting, and the lower-case "p", which has a calligraphic tail on the left reminiscent of italics such as those cut by William Caslon in the eighteenth century. The italic "e" is more restrained, with a straight line on the underside of the bowl where serif fonts normally add a curve.[d] Like most serif fonts, several weights and releases of Gill Sans use ligatures to allow its expansive letter "f" to join up with or avoid colliding with following letters.
The basic letter shapes of Gill Sans do not look consistent across styles (or even in the metal type era all the sizes of the same style), especially in Extra Bold and Extra Condensed widths, while the Ultra Bold style is effectively a different design altogether and was originally marketed as such. Digital-period Monotype designer Dan Rhatigan, author of an article on Gill Sans's development after Gill's death, has commented: "Gill Sans grew organically ... [it] takes a very 'asystematic' approach to type. Very characteristic of when it was designed and of when it was used." (At this time the idea that sans-serif typefaces should form a consistent family, with glyph shapes as consistent as possible between all weights and sizes, had not fully developed: it was quite normal for families to vary as seemed appropriate for their weight until developments such as the groundbreaking release of Univers in 1957.)
In the light weights, the slanting cut at top left of the regular "t" is replaced with two separate strokes.[e] From the bold weight upwards Gill Sans has an extremely eccentric design of "i" and "j" with the dots (tittles) smaller than their parent letter's stroke.
Morison commissioned Gill to develop Gill Sans after they had begun to work together (often by post since Gill lived in Wales) on Gill's serif design Perpetua from 1925 onwards; they had known each other since about 1913. Morison visited Cleverdon's bookshop while in Bristol in 1927 where he saw and was impressed by Gill's fascia and alphabet. Gill wrote that "it was as a consequence of seeing these letters" that Morison commissioned him to develop a sans-serif family.[f]
In the period during and after his closest collaboration with Johnston, Gill had intermittently worked on sans-serif letter designs, including an almost sans-serif capital design in an alphabet for sign-painters in the 1910s, some "absolutely legible-to-the-last-degree ... simple block letters" for Army and Navy Stores in 1925 and some capital letter signs around his home in Capel-y-ffin, Wales.[g] Gill had greatly admired Johnston's work on their Underground project, which he wrote had redeemed the sans-serif from its "nineteenth-century corruption" of extreme boldness. Johnston apparently had not tried to turn the alphabet (as it was then called) that he had designed into a commercial typeface project. He had tried to get involved in type design before starting work on Johnston Sans, but without success since the industry at the time mostly created designs in-house. Morison similarly respected the design of the Underground system, one of the first and most lasting uses of a standard lettering style as corporate branding (Gill had designed a set of serif letters for W.H. Smith), writing that it "conferred upon [the lettering] a sanction, civic and commercial, as had not been accorded to an alphabet since the time of Charlemagne".
Morison and Gill had met with some resistance within Monotype while developing Perpetua and while Morison was an enthusiastic backer of the project, Monotype's engineering manager and type designer F. H. Pierpont was deeply unconvinced, commenting that he could "see nothing in this design to recommend it and much that is objectionable". (Pierpont was the creator of Monotype's previous mainstay sans-serif, a loose family now called Monotype Grotesque. It is a much less sculptured design inspired by German sans-serifs.) Morison also intervened to insist that the letters "J" and "Q" be allowed to elegantly descend below the baseline, something not normal for titling typefaces which were often made to fill up the entire area of the metal type. In the early days of its existence it was not always consistently simply called "Gill Sans", with other names such as "Gill Sans-serif", "Monotype Sans-Serif" (the latter two both used by Gill in some of his publications) or its order numbers (such as Series No. 231) sometimes used.
A large amount of material about the development of Gill Sans survives in Monotype's archives and in Gill's papers. While the capitals (which were prepared first) resemble Johnston quite closely, the archives document Gill (and the drawing office team at Monotype's works in SalfordsSurrey, who developed a final precise design and spacing) grappling with the challenge of creating a viable humanist sans-serif lower-case as well as an italic, which Johnston's design did not have.[h] Gill's first draft proposed many slanting cuts on the ends of ascenders and descenders, looking less like Johnston than the released version did, and quite long descenders. Early art for the italic also looked very different, with less of a slope, again very long descenders and swash capitals.[i] The final version did not use the calligraphic italic "g" Gill preferred in his serif designs Perpetua and Joanna (and considered in the draft italic art), instead using a standard "double-storey" "g".
In the regular or roman style of Gill Sans, some letters were simplified from Johnston, with diamond dots becoming round (rectangles in the later light weight) and the lower-case "L" becoming a simple line, but the "a" became more complex with a curving tail in most versions and sizes. In addition, the design was simply refined in general, for example by making the horizontals slightly narrower than verticals so that they do not appear unbalanced, a standard technique in font design which Johnston had not used. The "R" with its widely splayed leg is Gill's preferred design, unlike that of Johnston; historian James Mosley has suggested that this may be inspired by an Italian Renaissance carving in the Victoria and Albert Museum in London. Particular areas of thought during the design process were the "a" (several versions and sizes in the hot metal era had a straight tail like Johnston's or a mildly curving tail) and the "b", "d", "p" and "q", where some versions (and sizes, since the same weight would not be identical at every size) had stroke ends visible and others did not.[j] Rhatigan has commented that Monotype's archives contain "enough [material] for a book just about the 'b', 'd', 'p', and 'q' of Gill Sans".
The titling capitals of Gill Sans were first unveiled at a printing conference in 1928; it was also shown in a specimen issued in the Fleuron magazine edited by Morison. While initial response was partly appreciative, it was still considered dubious by some ultra-conservative printers who saw all sans-serif type as modern and unsound; one called it "typographical Bolshevism". Sans-serifs were still regarded as vulgar and commercial by purists in this period: Johnston's pupil Graily Hewitt privately commented of them that:
In Johnston I have lost confidence. Despite all he did for us ... he has undone too much by forsaking his standard of the Roman alphabet, giving the world, without safeguard or explanation, his block letters which disfigure our modern life. His prestige has obscured their vulgarity and commercialism.
Nonetheless, Gill Sans rapidly became popular after its release.
Gill Sans' technical production followed Monotype's standard method of the period. The characters were drawn on paper in large plan diagrams by the experienced drawing office team, led and trained by American engineer Frank Hinman Pierpont and Fritz Steltzer, both of whom Monotype had recruited from the German printing industry. The drawing staff who executed the design was disproportionately female and in many cases recruited from the local area and the nearby Reigate art school; they worked out many aspects of the final drawings including adaptations of the letters to different sizes and the spacing. The diagrams were then used as a plan for machining metal punches by pantograph to stamp matrices, which would be loaded into a casting machine to cast type. It was Monotype's standard practice at the time to first engrave a limited number of characters and print proofs (some of which survive) from them to test overall balance of colour and spacing on the page, before completing the remaining characters.Walter Tracy, Rhatigan and Gill's biographer Malcolm Yorke have all written that the drawing office's work in making Gill Sans successful has not been fully appreciated; Yorke described Gill as "tactless" in his claims that the design was "as much as possible mathematically measurable ... as little reliance as possible should be placed on the sensibility of the draughtsmen and others concerned in its machine facture".
Gill Sans rapidly became very popular. Its success was aided by Monotype's sophisticated marketing, led by Gill's supporter (and sometime lover) Beatrice Warde, and due to its practicality and availability for machine composition in a very wide range of sizes and weights.
Despite the popularity of Gill Sans, some reviews have been critical. Robert Harling, who knew Gill, wrote in his 1976 anthology examining Gill's lettering that the density of the basic weight made it unsuitable for extended passages of text, printing a passage in it as a demonstration. The regular weight has been used to print body text for some trade printing uses such as guides to countryside walks published by the LNER system.William Addison Dwiggins described it and Futura as "fine in the capitals and bum in the lower-case" while proposing to create a more individualistic competitor, Metro, for Linotype around 1929. Modern writers, including Stephen Coles and Ben Archer, have criticised it for failing to improve on Johnston and for unevenness of colour, especially in the bolder weights (discussed below). More generally, modern font designer Jonathan Hoefler has criticised Johnston and Gill's designs for rigidity, calling their work "products more of the machine than the hand, chilly and austere designs shaped by unbending rules, whose occasional moments of whimsy were so out of place as to feel volatile and disquieting.”
Gill broached the topic of the similarity with Johnston in a variety of ways in his work and writings, writing to Johnston in 1933 to apologise for the typeface bearing his name and describing Johnston's work as being important and seminal. However, in his Essay on Typography, he proposed that his version was "perhaps an improvement" and more "fool-proof" than Johnston's. Johnston and Gill had drifted apart by the beginning of the 1920s, something Gill's groundbreaking biographer Fiona MacCarthy describes as partly due to the anti-Catholicism of Johnston's wife Greta.Frank Pick, the Underground Electric Railways Company managing director who commissioned Johnston's typeface, privately thought Gill Sans "a rather close copy" of Johnston's work.
Expansion and new styles
Following the initial success of Gill Sans, Monotype rapidly produced a wide variety of other variants. In addition, Monotype sold moulds (matrices) for Gill Sans in very large sizes for their "Supercaster" type-casting equipment. Popular with advertisers, this allowed end-users to cast their own type at a very competitive price. This made it a popular choice for posters. Gill's biographer Malcolm Yorke has described it as "the essence of clarity for public notices".
Versions of Gill Sans were created in a wide range of styles such as condensed and shadowed weights. Several shadowed designs were released, including a capitals-only regular shadowed design and a light-shadowed version with deep relief shadows. In the metal type era, a 'cameo ruled' design that placed white letters in boxes or against a stippled black background was available. The shadowed weights were intended to be used together with the regular, printing in different colours, to achieve a simple multicolour effect. Some of the decorative versions may predominantly have been designed by the Monotype office, with Gill examining, critiquing and approving the designs sent to him by post. The long series of extensions, redrawings and conversions into new formats of one of Monotype's most important assets (extending long beyond Gill's death) has left Gill Sans with a great range of alternative designs and releases. A book weight was created in 1993 in between the light and regular weight, suitable for body text, along with a heavy weight.
In 1936, Gill and Monotype released an extremely bold sans-serif named Gill Kayo (from KO, or knockout, implying its solidity). This has often been branded as Gill Sans Ultra Bold, though in practice many letters vary considerably from Gill Sans. It is available in regular and condensed widths. Gill, who thought of the design as something of an eccentricity, considered naming it "Double Elefans". Harling reviewed it as "dismal" and sarcastically commented that "typographical historians of 2000AD (which isn't, after all, so very far away) will find this odd outburst in Mr Gill's career, and will spend much time in attempting to track down this sad psychological state of his during 1936." Forty years later he described it as "the most horrendous and blackguardly of these display exploitations". The design was begun in 1932; some initial drawings of Kayo may have been prepared by Gill's son-in-law Denis Tegetmeier. It made a return to popularity in the graphic design of the 1970s and 80s.
The boldest weights of Gill Sans, including Kayo, have been particularly criticised for design issues such as the eccentric design of the "i" and "j", and for their extreme boldness. (Gill Sans' standard weight is, as already noted, already quite bold by modern standards.) Gill argued in his Essay on Typography that the nineteenth-century tendency to make sans-serif typefaces attention-grabbingly bold was self-defeating, since the result was compromised legibility. In the closing paragraph he ruefully noted how he had contributed to the genre:
There are now about as many different varieties of letters as there are different kinds of fools. I myself am responsible for designing five different sorts of sans-serif letters – each one thicker and fatter than the last because each advertisement has to try and shout down its neighbours.
Monotype developed a set of alternate characters for Gill Sans to cater for differing tastes and national printing styles of different countries. These include Futura-inspired designs of "N", "M", "R", "a", "g", "t" and others, a four-terminal "W" in the French renaissance style, a tighter "R", a "Q" in the nineteenth-century style with a tail that looped upwards (similar to that on Century among others, and preferred by the LNER), oblique designs as opposed to the standard true italic, a more curving, true-italic "e" and several alternative numerals. In particular, in the standard designs for Gill Sans the numeral "1", upper-case "i" and lower-case "L" are all a simple vertical line, so an alternate "1" with a serif was sold for number-heavy situations where this could otherwise cause confusion, such as on price-lists. (Not all timetables used it: for example, the L.N.E.R. preferred the simple version.) Some early versions of Gill Sans also had features later abandoned, such as an unusual "7" matching the curve of the "9", a "5" pushing forwards, and a lower-case letter-height "0".
Gill was involved in the design of these alternates, and Monotype's archive preserves notes that he rethought the geometric alternates. With the increasing popularity of Futura Gill Sans was not alone in being adapted: both Erbar and Dwiggins' Metro would undergo what historian Paul Shaw has called a "Futura-ectomy" to conform to taste. After Gill's death, Monotype created versions for the Greek and Cyrillic alphabets.[k] Monotype would also later add text figures to Gill Sans, numbers at the height of lower-case letters. Popular in design for body text, these are a traditional feature on serif fonts which Gill Sans did not originally have.
Series and styles
According to Rhatigan and other sources, by the end of the metal type period Gill Sans had been released in the following styles (not all sold at the same time):
- Gill Sans Titling (1928, series 231)
- Gill Sans (1930, series 262, sometimes called Gill Sans Medium)
- Gill Sans Bold (1930, series 275)
- Gill Sans Shadow Line (1931, series 290)[l]
- Gill Sans Shadow Titling (1931, series 304)[m]
- Gill Sans Bold Titling (1931, series 317)
- Gill Sans Extra Bold (1931, series 321)
- Gill Sans Light (1931, series 362)[n]
- Gill Sans Shadow (1932, series 338)[o]
- Gill Sans Bold Condensed (1932, series 343)
- Gill Sans 5pt (1932, series 349, sometimes called Gill Sans No. 2)
- Gill Sans Bold 5pt (1932, series 350, sometimes called Bold No. 2)
- Gill Sans Poster (1932, series 353)
- Gill Sans Bold Condensed Titling (1933, series 373)
- Gill Sans Cameo (1934, series 233)
- Gill Sans Cameo Ruled (1935, series 299)
- Gill Sans Shadow No. 1 (1936, series 406)[p]
- Gill Sans Shadow No. 2 (1936, series 408)[q]
- Gill Sans Ultra Bold (1936, series 442)
- Gill Sans Bold Extra Condensed (1937, series 468)
- Gill Sans Condensed (1937, series 485, sometimes called Medium Condensed)
- Gill Sans Bold No. 3 (1937, series 575)
- Gill Sans Bold Condensed Titling (1939, series 525)
- Gill Sans Extra Bold Titling (1939, series 526)
- Gill Sans Light 5pt (1958, series 662, sometimes called Light No. 2)
Titling series were capitals-only.
Monotype offered Gill Sans on film in the phototypesetting period. The fonts released in 1961 included Light 362, Series 262, Bold 275, Extra Bold 321, Condensed 343, all of which were released in film matrix sets "A" (6–7 points) and "B" (8–22, 24 points).
Infant and rounded versions
Monotype created an 'infant' version of Gill Sans using single-storey "a" and "g", and other more distinguishable characters such as a rounded "y", seriffed "1" and lower-case "L" with a turn at the bottom. Infant designs of fonts are often used in education and toys as the letters are thought to be more recognisable to children being based on handwriting, and are often produced to supplement popular families such as Gill Sans, Akzidenz-Grotesk and Bembo. Monotype also created a version with rounded stroke ends for John Lewis for use on toys.
The digital releases of Gill Sans fall into several main phases: releases before 2005 (which includes most bundled "system" versions of Gill Sans), the 2005 Pro edition, and the 2015 Nova release which adds many alternate characters and is in part included with Windows 10. In general characteristics for common weights the designs are similar, but there are some changes: for example, in the book weight the 2005 release used circular ij dots but the 2015 release uses square designs, and the 2015 release simplifies some ligatures. Digital Gill Sans also gained character sets not present in the metal type, including text figures and small capitals.
Like all metal type revivals, reviving Gill Sans in digital form raises several decisions of interpretation, such as the issue of how to compensate for the ink spread that would have been seen in print at small sizes more than larger. As a result, printed Gill Sans and its digital facsimile may not always match. The digital release of Gill Sans, like many Monotype digitisations, has been criticised, in particular for excessively tight letter-spacing and lack of optical sizes: with only one design released that has to be used at any text size, it cannot replicate the subtlety of design and spacing of the metal type, for which every size was drawn differently. In the hot metal era different font sizes varied as is normal for metal type, with wider spacing and other detail changes at smaller text sizes; other major sans-serif families such as Futura and Akzidenz-Grotesk are similar. In the phototype period Monotype continued to offer two or three sizes of master, but all of this subtlety was lost on transfer to digital. To replicate this, it is necessary to make manual adjustment to spacing to compensate for size changes, such as expanding the spacing and increasing the weight used at smaller sizes.[r]
Former ATypI president John Berry commented of Gill Sans' modernised spacing that "both the regular weight and especially the light weight look much better when they're tracked loose". In contrast, Walter Tracy wrote in 1986 that he preferred the later spacing: "the metal version ... was spaced, I suspect, as if it were a serif face".
Gill Sans Nova (2015)
As of 2017, Monotype's current digitisation of Gill Sans is Gill Sans Nova, by George Ryan. Gill Sans Nova adds many additional variants, including some of the previously undigitised inline versions, stylistic alternates and an ultra-light weight which had been drawn for Grazia. The fonts differ from Gill Sans MT in their adoption of the hooked 1 as default, while the regular weight is renamed 'Medium'. Monotype celebrated the release with a London exhibition on Gill's work, as they had in 1958 to mark the general release of Gill's serif design Joanna. One addition was italic swash caps, which had been considered by Gill but never released.
The family includes 43 fonts, including 33 text fonts in 9 weights and 3 widths, 6 inline fonts in 5 weights and 2 widths (1 in condensed), 2 shadowed fonts in 2 weights and 1 width, 1 shadowed outline font, 1 deco font. Characters set support includes W1G.
The basic set of Regular, Light and Bold weights is bundled with Windows 10.
First unveiled in a single uppercase weight in 1928, Gill Sans achieved national prominence almost immediately, when it was chosen the following year to become the standard typeface for the LNER railway system, soon appearing on every facet of the company's identity, from metal locomotive nameplates and hand-painted station signage to printed restaurant car menus, timetables and advertising posters. The LNER promoted their rebranding by offering Gill (who was fascinated with railway engines) a footplate ride on the Flying Scotsman express service; he also painted for it a signboard in the style of Gill Sans, which survives in the collection of the St Bride Library.
In 1949 the Railway Executive decided on standard types of signs to be used at all stations. Lettering was to use the Gill Sans typeface on a background of the regional colour. Gill Sans was also used in much of its printed output, very often in capitals-only settings for signage. Specially drawn variations were developed by the Railway Executive (part of the British Transport Commission) for signs in its manual for the use of signpainters painting large signs by hand. Other users included Penguin Books' iconic paperback jacket designs from 1935 and British official mapping agency Ordnance Survey. It was also used by London Transport for documents which could not be practically set in Johnston. Paul Shaw, a historian of printing, has described it as a key element of the 'Modernist classical' style from the 1930s to the 1950s, that promoted clean, spare design, often with all-capitals and centred setting of headings.
Gill Sans remains popular, although a trend away from it towards grotesque and neo-grotesque typefaces took place around the 1950s and 1960s under the influence of continental and American design. Typefaces that became popular around this time included original early "grotesque" sans-serifs, as well as new and more elegant designs in the same style such as Helvetica and Univers. Mosley has commented that in 1960 "orders unexpectedly revived" for the old Monotype Grotesque design: "[it] represents, even more evocatively than Univers, the fresh revolutionary breeze that began to blow through typography in the early sixties." He added in 2007 "its rather clumsy design seems to have been one of the chief attractions to iconoclastic designers tired of the ... prettiness of Gill Sans". As an example of this trend, Jock Kinneir and Margaret Calvert's corporate rebranding of BR as British Rail in 1965 introduced Helvetica and Univers for printed matter and the custom but very similar Rail Alphabet for signage, and abandoned the classical, all caps signage style with which Gill Sans is often associated. Kinneir and Calvert's road signage redesign used a similar approach. Linotype and its designer Hermann Zapf, who had begun development on a planned Gill Sans competitor in 1955, first considered redrawing some letters to make it more like these faces before abandoning the design project (now named "Magnus") around 1962-3.
An additional development which reduced Gill Sans' dominance was the arrival of phototypesetting, which allowed typefaces to be printed from photographs on film and (especially in display use – hot metal continued for some body text setting for longer) massively increased the range of typefaces that could cheaply be used. Dry transfers like Letraset had a similar effect for smaller projects; their sans-serif Compacta and Stephenson Blake's Impact exemplified the design trends of the period by choosing dense, industrial designs. Of the period from the 1930s to 1950s, when he was growing up, James Mosley would later write:
The Monotype classics dominated the typographical landscape ... in Britain, at any rate, they were so ubiquitous that, while their excellent quality was undeniable, it was possible to be bored by them and to begin to rebel against the bland good taste that they represented. In fact we were already aware by 1960 that they might not be around to bore us for too long. The death of metal type ... seemed at last to be happening.[s]
While extremely popular in Britain, and to a lesser extent in European printing, Gill Sans did not achieve popularity with American printers in the hot metal era, with most preferring gothic designs like Franklin Gothic and geometric designs like Futura and Monotype's own Twentieth Century.[t] Gill Sans therefore particularly achieved worldwide popularity after the close of the metal type era and in the phototypesetting and digital era, when it became a system font on Macintosh computers and Microsoft Office. One use of Gill's work in the United States in this period, however, was a custom wordmark and logo made by Gill for Poetry magazine in 1930 based on Gill Sans. Its editor Harriet Monroe had seen Gill's work in London.
The BBC adopted the typeface as its corporate typeface in 1997 for many but not all purposes, including on its logo. Explaining the change, designer Martin Lambie-Nairn said that "by choosing a typeface that has stood the test of time, we avoid the trap of going down a modish route that might look outdated in several years' time". The BBC had an earlier association with Gill, who created some sculptures on Broadcasting House. Other more recent British organisations using Gill Sans have included Railtrack (and initially its successor Network Rail), John Lewis and the Church of England, which adopted Gill Sans as the typeface for the definitive Common Worship family of service books published from 2000. Notable non-British modern businesses using Gill Sans include United Colours of Benetton (which commissioned a custom variant), Tommy Hilfiger and Saab Automobile. British rock band Bloc Party has used Gill Sans in its logo. AT&T used it until 2006, before changing it to Clearview after feeling that it was too in keeping with market research that people found the company "monolithic".Edward Tufte, the information design theorist, uses Gill Sans on his website and in some of his published works. The Wikimedia Foundation uses Gill Sans on its wordmark. The logo for Yamaha's Vocaloid singing synthesis software uses Gill Sans.
The Sheffield type foundry Stephenson Blake rapidly released a commercial competitor named Granby, influenced by Gill Sans, Johnston and Futura.
Using lower-case fonts varying only in serif size (0%, 5%, and 10% cap height), we assessed legibility using size thresholds and reading speed. Five percentage serif fonts were slightly more legible than sans serif, but the average inter-letter spacing increase that serifs themselves impose, predicts greater enhancement than we observed. RSVP and continuous reading speeds showed no effect of serifs. When text is small or distant, serifs may, then, produce a tiny legibility increase due to the concomitant increase in spacing. However, our data exhibited no difference in legibility between typefaces that differ only in the presence or absence of serifs.
Keywords: Legibility, Reading, Typography, Low vision
It is well accepted that typeface affects text readability (Mackeben, 1999; Mansfield, Legge, & Bane, 1996; Roethlein, 1912; Tinker, 1963; Whittaker, Rohrkaste, & Higgins, 1989), but apart from a few studies (Arditi, 1996; Arditi, Cagenello, & Jacobs, 1995a, Arditi, Cagenello, & Jacobs, 1995b; Arditi, Knoblauch, & Grunwald, 1990; Arditi, Liu, & Lynn, 1997; Berger, 1944a, 1944b, 1948) few experiments have addressed how carefully controlled, specific characteristics of font design contribute to legibility. One reason for the paucity of research in this area is that it is only since the advent of computer fonts that it has it been reasonably easy to construct fonts that can be varied parametrically. Indeed, most studies assessing the impact of font characteristics that use pre-existing fonts have difficulty drawing definitive conclusions since virtually all such fonts differ in more than a single characteristic (e.g., Mansfield et al., 1996; Yager, Aquilante, & Plass, 1998).
In the present study, we address the issue of how the presence or absence of serifs contributes to readability both at typical print sizes and close to the acuity limit. To be able to draw firmer conclusions, we used fonts of our own design that differ only in the presence or absence, and size of serifs. Since illegible typography appears to be a common complaint among people with impaired vision, we also included two readers with age-related macular degeneration (AMD) in our sample of subjects. Given the small sample size, however, we cannot draw firm or general conclusions about low vision from these data.
In the typographic literature, serifs are generally believed to have a significant impact on readability. There are two main reasons cited to explain why serifs should enhance legibility. First, they are believed to increase letter discriminability by making the spatial code of letter forms more complex. A well-known authority on typography writes:
“Sans-serif type is intrinsically less legible than seriffed type…because some of the letters are more like each other than letters that have serifs, and so the certainty of decipherment is diminished.” (McLean, 1980)
Second, serifs are thought to increase the visibility of the ends of strokes, increasing the salience of the main strokes of the letters Rubinstein (1988) writes:
“Serifs have an important role in the readability of type, providing…accentuation to the ends of strokes that may help the reader read faster and avoid fatigue.”
Serifs might thus enhance legibility of individual letters by providing an additional cue to the location of stroke ends.
A third possible reason, possibly implied by the above quotation from Rubinstein, but not clearly articulated, is that those horizontal serifs that sit along the font baseline might conceivably enhance the ability of the reader to track the line of type with eye movements and hence may promote faster or more efficient reading.
On the other hand, there are also good reasons to believe that serifs have little effect on legibility. Being small relative to letter size, and generally being ornamental, rather than essential parts of the letter form, one might suspect that they would have little impact on letter identification. If they do affect legibility, it might be reasonable to suppose that they interfere with letter recognition, since to a simple letter-form template, they might simply act as a form of noise.
Empirical studies, also, have shown that spatial frequency information in letters, above 2–3 c/letter, is unnecessary for letter recognition (Ginsburg, 1981), and to support maximum reading speeds (Legge, Pelli, Rubin, & Schleske, 1985). Since serifs are largely comprised of such high spatial frequency information, one might suppose from these results, that they are irrelevant to legibility, especially at the acuity limit, where spatial frequencies higher than 2–3 c/letter are likely to be greatly attenuated by the optics of the eye.
Do fonts with serifs measurably enhance readability? We sought to determine whether or not these tiny features, which are clearly optional for basic letter recognition, have positive, negative, or no impact on legibility. Our criteria for demonstrating increased legibility were decreased size thresholds and increased reading speeds. Since the addition of serifs to a font increases the average inter-letter spacing of the font slightly (to accommodate the serifs), we explicitly varied inter-letter spacing as well, to independently assess its effects. And since illegible typography is a common complaint of people with low vision, we also included two observers with age-related maculopathy in our participant pool.
We assessed relative legibility of fonts with different size (or no) serifs, and with different inter-letter spacing using three different criteria for legibility:
Size thresholds (visual acuity) for letter identification, measured with five-letter, random, lower-case strings presented on a video monitor, using an up–down staircase (Levitt, 1971) with 0.05 log unit size steps. Size (or, inversely, distance) thresholds are probably the most common method of assessing text legibility (Tinker, 1963), and it is widely used in applied settings such as highway signage, with lower size thresholds indicating higher legibility.
Reading speeds using rapid serial visual presentation (RSVP). More legible fonts, by this criterion, allow faster reading, while less legible fonts prevent faster reading. We measured reading speed using RSVP with large letters (about seven times threshold size), and conventional mixed-case text from an expanded MNREAD (Legge, Ross, Luebker, & LaMay, 1989) corpus. Reading speed is a less common measure of legibility but it is perhaps more representative of ordinary reading than is size threshold. And because RSVP can support extremely high rates of reading, it has the potential to be more sensitive to subtle differences in legibility. RSVP reading was tested with individual sentences, whose speed was varied to determine the speed that supported a 50% correct reading rate.
Reading speeds using continuous reading of scrambled text passages using conventional text, printed on paper. We included this condition to address possible differences between reading speeds with RSVP on a computer monitor with those more commonly observed with continuous reading on paper. We used scrambled text to be able to compare performance on three different conditions within subjects while using text samples that have word frequency statistics that are representative of ordinary text, but which require reading of each individual word, rather than allowing context and inference to play a significant role in determining reading speed.
We constructed nine fonts using custom software (Arditi, 2004) that allows parametric font construction. Most of the font parameters are expressed as a proportion of the cap height, which is the height of an upper-case letter. The base font was constructed using strokes of uniform thickness that was 10% of the cap height. The fonts had serifs whose strokes were of the same 10% cap height thickness, and extended 0%, 5% or 10% of the cap height. Each of these three serif sizes had space added to their side bearings such that inter-letter spacing was 0%, 10%, or 40% of the cap height. This space was added only at the edges of the letter glyph so that the letter shape was unaltered by the manipulation of spacing. The full alphabet is displayed for three sizes of serifs (0%, 5%, and 10% cap height) in Fig. 1, and the three spacing conditions can be seen in Fig. 2. Other parameter values for the font that were constant for the entire set of nine fonts used in the experiment are: x-height: 55% cap height; and descent: 50% cap height. Parameter values other than serif size and spacing were chosen because they produce a reasonably natural appearing font, but are otherwise arbitrary. Most important, they are the same for all conditions of these experiments. In other words, the shapes of letter glyphs were unchanged over all conditions, except for the absence, presence, and size of serifs. All other published studies that have examined the effects of serifs have used existing, rather than custom fonts, and none have been able to conclusively separate effects of serifs from other font design characteristics.
The full font (alphabetic characters) used in the study. The letters are spaces with 10% cap height.
Examples of lower-case fonts used in, and created for, the experiment, Fonts differed only in size of serifs and by inter-letter spacing. Both parameters are defined in units of percent of the height of a capital letter in the font, which is also equal...
The nine fonts were used for all text employed in these experiments, presented on both computer monitor and paper.
3.1. Size thresholds
In this experiment, random five-letter strings were presented centered on a SONY Multiscan 520GS monitor, as black (3.6 cd/m2) letters on a white (129 cd/m2) background. Normally sighted subjects viewed the screen optically folded through a front-surface mirror at an optical distance of 788.4 cm, so that letters were at least 100 pixels in height (from the top of an uppercase letter to bottom of the descent), or equivalently, for these fonts, 66.66 pixels in cap height. For these subjects, the letters were rendered in reverse on the screen to compensate for the mirror reversal. Subjects with low vision viewed the screen directly (i.e., with no mirror) at viewing distances of 106 (subject SM) and 58.4 cm (subject MG). The letter strings were sampled (with replacement) from the 26 lower-case letters of the English alphabet. Examples of such strings for the nine font conditions are illustrated in Fig. 2.
3.2. RSVP reading
We used custom software to present each word of a sentence centered vertically and horizontally on the computer monitor, for a constant time interval. Text was black on white, as with the size thresholds. The participant read aloud each sentence as it was presented, prior to presentation of the next sentence.
3.3. Continuous reading of scrambled text
Three text passages of roughly ninth grade-level reading difficulty, and length 376, 400, and 405 words, respectively, were used. The words of each passage were randomly permuted, and printed on ordinary letter size white paper, in 18 pt type. The subject read the text aloud continuously, while the experimenter timed the reading of the entire passage and recorded errors.
Normally sighted participants were Lighthouse research staff (JC, CC), one of whom is an author of this paper, or recruited from the Lighthouse International Volunteer Service (AG, IF). Participants with low vision, both of whom had age-related maculopathy, were recruited from the Lighthouse Low Vision Service (MG, SM). MG’s distance acuity, measured with a trans-illuminated Lighthouse/ETDRS distance acuity chart, was 1.0 log MAR (20/200), while SM’s was 0.6 (20/80). Participants were seated comfortably in a chair, with their head position fixed with a head and chin rest. All participants, except JC (who participated only in Experiment 1), were naïve to the purposes of the experiment.
4. Experiment 1: Size thresholds
Size thresholds were measured using a staircase method (Levitt, 1971) in which correct identification of at least four of five letters (in correct order) was required for a decrease in letter size on the subsequent trial, while no more than three letters correct elicited a size increase on the subsequent trial. This procedure converges on the 68.6% correct point on the psychometric function. Subjects were required to give five-letter responses to all trials, and were encouraged to guess if they reported difficulty, On trials in which the size changed, the magnitude of the change was 0.05 log unit, half the size change from line to line on state-of-the-art visual acuity charts. Data prior to the 2nd reversal of each staircase were discarded, to concentrate the data used in the analysis close to the threshold.
To minimize sequence artifacts, the nine stimulus conditions were randomly permuted once for each subject. First, that random sequence of nine conditions was run in order, with each staircase terminating after 15 reversals. Next, the same sequence was run in reverse order with each staircase terminating after 30 reversals. Finally, the sequence was run in forward order again with termination after 15 reversals. Thus, each condition was run with a total of 60 staircase reversals, 30 in the forward randomized order and 30 in the reverse randomized order.
All responses were given verbally by the subject; the experimenter typed the responses into the computer, which then presented the next five-letter string whose size was contingent on the subject’s performance. Subjects were thus able to change their responses if they did so prior to the experimenter’s finalizing the response to that line. This procedure results in a negligible lapse or extraneous noise rate (Arditi, 2005).
Size thresholds are shown as a function of serif size and inter-letter spacing for the four normally sighted participants in Fig. 3 and the two participants with low vision in Fig. 4. These thresholds are geometric means of all the staircase levels visited (after the second reversal of each run); the number of measurements on which the thresholds were based ranged from 69 to 107. Standard errors (SEs) about these means (which reflect accuracy of values in terms of proportion, rather than magnitude) were small; the maximum SE over all participants and all stimulus conditions was 0.0026.
Letter size threshold as a function of inter-letter spacing and serif size (squares: 0, circles: 5, and triangles: 10% cap height) for four normally sighted participants. Serif size has a nearly negligible impact on size threshold relative to spacing,...
Same as Fig. 3 but for two observers with age-related maculopathy. Note different scale from Fig. 3. Results are similar to those of normally sighted observers.
All of the plots slope downward as spacing increases, indicating the presence of a large inter-letter spacing “crowding” effect, in which closely spaced letters result in higher size (acuity) thresholds. Also evidents are much smaller, but systematic effects of serif size on threshold, with the threshold for the 5% serif nearly always being lower than that of the smallest (zero) serif size. Averaged data are shown in Figs. 5 and 6, for normal and low vision, respectively, and in Fig. 7 for all subjects. Note that the results are essentially the same for the low vision subjects—those for whom, some might argue, serifs should make a difference.
Average (geometric mean) normal vision data form Experiment 1.
Average (geometric mean) low vision data from Experiment 1.
Data of all subjects averaged (geometric mean) from Experiment 1.
The above observations were corroborated with an analysis of variance (ANOVA) performed on normalized thresholds. First, so that data from the low vision and normal vision groups could be combined, each subject’s data were transformed by dividing each data point by that subject’s minimum threshold, yielding a score normalized to the subject’s best performance. The log of this ratio was then used as the dependent variable in an ANOVA with independent variables serif size, inter-letter spacing, and vision status (normal or low), and repeated measures on serif size, and inter-letter spacing. The only significant effects were spacing (F[2,8] = 143.888, p = 0.000) and serif size (F[2,8] = 10.120, p = 0.006).
5. Experiment 2: Rapid serial visual presentation reading
In this experiment, we assessed the affect of serif size on reading using the RSVP reading technique. This technique, in which words are presented one at a time in the center of the computer monitor, allows reading at higher speeds than with continuous verbal reading (Rubin & Turano, 1994; Rubin & Turano, 1992), especially for normally sighted readers (Rubin & Turano, 1992), and therefore might plausibly be more sensitive to subtle differences in legibility. To further enhance this sensitivity, we used sentences from an expanded MNREAD corpus. These sentences are by design 56 characters long (including interior spaces) with comparable comprehensibility (See Mansfield, Ahn, Legge, & Luebkerr, 1993 for details). Since the sentences are very short, readers can store most or all of each sentence in short-term memory, and report the sentence verbally without needing to maintain a high rate of verbal output, which might otherwise limit speeds. Word presentation rate, which was controlled by a desktop computer, was varied only between sentences, by an amount that was contingent on reading error rate.
We compared only the three fonts with 10% cap height spacing using this technique, because we had a limited number of 56-character MNREAD sentences (357), and wanted to obtain error rates for a range of presentation rates. Subjects were given practice on 60-character MNREAD sentences prior to testing.
The experimenter determined informally during the practice phase the speed region in which the subject began to make errors, by increasing speed by 20% if no errors were made, and decreasing speed if errors were made. Once data collection began, the speed increments and decrements were reduced to 10% and data collection proceeded in staircase fashion, such that if no errors were made, the speed was increased; if no words in the sentence were correctly identified, the speed was reduced. Our goal was thus to obtain nonzero error rates for several presentation speeds, sampling a wide range of the sloping portion of the psychometric function. We obtained estimates of between 5 and 10 speeds for each of the three conditions, for each subject. Error rates (in characters per 56-character sentence) were then fit by probit (Finney, 1971), to a cumulative Gaussian. Maximum reading speed was taken to be the speed in words per minute, at which 50% errors were made. Following the method of Carver (1976), speeds in words per minute were computed by assuming that each sentence was composed of 9.33 standard length words (each six letters in length) and dividing by the exposure time for the sentences.
Viewing distances and font sizes were chosen to approximate an acuity reserve of about seven, easily enough for comfortable reading (see Table 1).
Viewing distance, font x-height, log minimum angle of resolution (log MAR) and acuity reserve for the four participants of Experiment 2
Fifty percent of correct RSVP speed thresholds for the four participants reading the three fonts are shown in Fig. 8. The data show no systematic effect of serif size on reading speed. This was corroborated by a repeated measures ANOVA, which resulted in no significant effects.
RSVP reading speeds for 10% cap height letter spacing, as a function of serif size. Speeds correspond to % error rate, as fit by probit. Participants MG and SM have low vision, while IF and AG have normal vision.
Note the high reading speeds measured for normally sighted subjects AG and IF. Very high speeds have previously been reported by Rubin and Turano (1992). Our use of short sentences may have made such high rates possible, since the reader could keep the entire sentence in short-term memory prior to reporting it. Also, the reading speeds we report (for computational convenience) correspond to an estimated 50% character error rate, which is a much higher error rate than would be tolerated in ordinary reading.
6. Experiment 3: Continuous reading on paper
Participants were given the scrambled reading passages and asked to read them aloud as quickly and accurately as possible. The two subjects with low vision (MG and SM) used their customary optical reading aids, which were a 6× Eschenbach halogen illuminated stand magnifier (MG) and a 4× Eschenbach torch hand magnifier (SM). Participants were allowed to hold the passages in their hands, and no attempt was made to control or advise reading distance. Reading of the passages was timed with a stop watch and errors recorded. Credit was given for each whole word read correctly. Reading speed was taken as the number of characters within correctly read words divided by the time taken to read the passage.
Reading speeds, in characters per minute, are shown for each subject in Fig. 9. Again, there are no systematic differences in reading speed as a function of serif size, and, as with RSVP reading, this was corroborated by failure to find any significant effect in a repeated measures ANOVA.
Continuous reading speeds for text with 10% cap height letter spacing, as a function of serif size. Participants MG and SM have low vision, while IF and CC have normal vision.
7. Discussion and conclusion
In Experiments 2 and 3, the presence or absence of serifs made no difference in reading speed, for all participants, both normally sighted and those with low vision. Only in Experiment 1, which used an acuity criterion of legibility, was a statistical effect of serif size observed. The size of the observed effect was extremely small, however. Looking at the average data of Fig. 7, the range of the size threshold fell within 3.14 arc min (or about 0.11 of the threshold) for the zero spacing condition, 1.76 arc min (0.08 threshold) for the 10 min spacing condition, and 0.14 arc min (0.01 threshold) for the 40 min condition, with the intermediate (5% cap height) serifs yielding the lowest thresholds, and highest legibility.
Note that a small degree of legibility enhancement would be expected for serifs due to the increased letter spacing that the addition of the serifs requires. In the fonts used in the current experiment, 14 of 26 of the letters have serifs along the baseline that add separation between the letters. On average, the increased separation is equal to 14/26 × serif size. For the 5% serif font, the increase in letter spacing is 2.69% cap height; for the 10% serif font, the increase is 5.38%. The average slope of the linear segment between 0 spacing and 10% cap height spacing is −2.56; that is, for each percent cap height increase in letter spacing, threshold decreases by 2.56 arc min. The 5% serif, then, should provide a 2.69 × 2.56 = 6.88 arc min reduction in size threshold, while the 10% serif should result in a 2.56 × 5.38 = 13.77 arc min reduction, on the basis of increased letter spacing alone. These reductions are far greater than those observed, and therefore we conclude that, at least at very small letter sizes, close to the acuity limit, serifs may actually interfere ever so slightly with legibility. This reduction is more than offset by an enhancement of legibility caused by the increased spacing that results from the addition of serifs, so the net effect is one of slightly enhanced legibility for the intermediate (5% serif) fonts.
This could also help explain why the slight enhancement of legibility due to increased spacing due to serifs is no longer seen in the 10% serif font, which has even wider spacing. It is certainly plausible to posit that in the case of the 5% serif, the serif and the additional letter spacing required to accommodate it has a legibility-enhancing effect that is stronger than any legibility-reducing effect of the serif. But in the case of the 10% serif, more inter-letter spacing does not outweigh the serifs stronger legibility-reducing effect, perhaps because the relief from crowding is greater when inter-letter separation is zero, while the serifs legibility-reducing effect may be independent of spacing. The idea that serifs might reduce legibility is also consistent with the recent finding of Morris, Aquilante, Yager, and Bigelow (2002), who found reductions in RSVP reading speed with seriffed but not sans-serif type at sizes close to the acuity limit (4 pt type at 40 cm), and not at larger sizes.
We wish to offer three concluding caveats. First, we have only studied a single font of our own parametric design. It is possible that serifs in other fonts, especially those designed with the critical eye of an expert font designer, may have more of an impact. On the other hand, while our font choices were to a degree arbitrary, we can think of no reason why they would bias our results against finding stronger serif effects on legibility.
Second, we have used a small sample of participants. It is certainly plausible that subtle differential legibility effects of legibility could emerge from a larger study. The present results are best taken to mean that substantial legibility effects are absent; we can conclude little about more subtle effects.
Third, while two subjects with AMD were included in the participant sample, no firm or general conclusions can be drawn about AMD or low vision, with respect to font legibility. Again, if such effects exist, they are either subtle enough to be undetected by our experimental methods, or they exist only within a subpopulation not well represented by our two subjects with AMD.
In sum, we did find a small effect of serifs on size thresholds, but it is unlikely to be of significance at typical print sizes viewed under normal conditions. While subtle effects on reading rate may emerge with larger subject samples, the miniscule differences we found with this small sample were apparent only with visually tiny print.
We thank Gordon Legge, Steve Mansfield, Beth O'Brien, and Lee Zimmerman for the expanded MNREAD corpus used in this study, and Kathryn Hargreaves for help with the font design, and two anonymous reviewers for insightful comments. The work was partially supported by NIH Grants EY12465, AG14586, and EY015192, and grants from the Hoffritz and Pearle Vision Foundations.
- Arditi A. Typography, print legibility and low vision. In: Cole BRR, editor. Remediation and management of low vision. St. Louis: Mosby; 1996. pp. 237–248.
- Arditi A. Adjustable typography: An approach to enhancing low vision text accessibility. Ergonomics. 2004;47(5):469–482.[PubMed]
- Arditi A. Lapse resistance in the verbal letter reporting task: Implications for the design of clinical psychophysical tests. Vision Research. 2005[PMC free article][PubMed]
- Arditi A, Cagenello R, Jacobs B. Effects of aspect ratio and spacing on legibility of small letters. Supplement to Investigative Ophthalmology and Visual Science. 1995a;36(4):671.
- Arditi A, Cagenello R, Jacobs B. Letter stroke width, spacing, and legibility. Paper presented at the Optical Society of America; Washington, DC. 1995.
- Arditi A, Knoblauch K, Grunwald I. Reading with fixed and variable character pitch. Journal of the Optical Society of America A. 1990;7:2011–2015.[PubMed]
- Arditi A, Liu L, Lynn W. Legibility of outline and solid fonts with wide and narrow spacing. In: Yager D, editor. Trends in optics and photonics. Vol. 11. Washington, DC: Optical Society of America; 1997.
- Berger C. Stroke-width, form and horizontal spacing of numerals as determinants of the threshold of recognition i. Journal of Applied Psychology. 1944a;28:208–231.
- Berger C. Stroke-width, form and horizontal, spacing of numerals as determinants of the threshold of recognition ii. Journal of Applied Psychology. 1944b;28:336–346.
- Berger C. Experiments on the legibility of symbols of different width and height. Acta Ophthalmologica. 1948;26:423–434.[PubMed]
- Carver RP. Word length, prose difficulty, and rending rate. Journal of Reading Behavior. 1976;8:193–203.
- Finney DJ. Probit analysis. 3rd ed. Cambridge: Cambridge University Press; 1971.
- Ginsburg AP. Spatial filtering and vision Implications for normal and abnormal vision. In: Proenza LM, Enoch JM, Jampolsky A, editors. Clinical applications of visual psychophysics. New York: Cambridge University Press; 1981.
- Legge GE, Pelli DG, Rubin GS, Schleske MM. Psychophysics of reading. I. Normal vision. Vision Research. 1985;25:239–252.[PubMed]
- Legge GE, Ross JA, Lucbker A, LaMay JM. Psychophysics of reading. Viii. The minnesota low-vision reading test. Optometry and Vision Science. 1989;66(12):843–853.[PubMed]
- Levitt H. Transformed up-down methods in psychoacoustics. Journal of the Acoustical Society of America. 1971;49:466–477.[PubMed]
- Mackeben M. Typefaces influence peripheral letter recognition and can be optimized for reading with eccentric viewing. Paper presented at the Vision 99; New York, NY. 1900.
- Mansfield JS, Ahn SJ, Legge GE, Luebkerr A. A new reading-acuity chart for normal and low vision. OSA Technical Digest. 1993;3:232–235.
- Mansfield JS, Legge GE, Bane MC. Psychophysics of reading Xv: Font effects in normal and low vision. Investigative Ophthalmology and Visual Science. 1996;37(8):1492–1501.[PubMed]
- McLean R. The thames and hudson manual of typography. Vol. 1. London, UK: Thames and Hudson Ltd; 1980.
- Morris R, Aquilante K, Yager D, Bigelow C. Serifs slow rsvp reading at very small sizes, but don’t matter at larger sizes; Society for Information Display International Symposium Digest of Technical Papers; 2002. p. 13.
- Roethlein BE. The relative legibility of different faces of printing types. The American Journal of Psychology. 1912;23(1):1–36.
- Rubin GS, Turano K. Low vision reading with sequential word presentation. Vision Research. 1994;34(13):1723–1733.[PubMed]
- Rubin GS, Turano KA. Reading without saccadic eye movements. Vision Research. 1992;32(5):895–902.[PubMed]
- Rubinstein R. Digital typography: An introduction to type and composition for computer system design. Boston, MA: Addison Wesley; 1988.
- Tinker MA. Legibility of print, Ames. Iowa: Iowa State University Press; 1963.
- Whittaker S, Rohrkaste F, Higgins KE. Noninvasive assessment of the visual system. Technical digest series. Vol. 7. Washington, DC: Optical Society of America; 1989. Optimum letter spacing for word recognition in central and eccentric fields.
- Yager D, Aquilante K, Plass R. High and low luminance letters, acuity reserve, and font effects on reading speed. Vision Research. 1998;38:2527–2531.[PubMed]