Fonts, height and reading speed
Reading performance was also measured with text that was defined by differing amounts
of color and luminance contrast, in order to determine the influence of color information
on reading. Results indicated that when luminance contrast was well above threshold,
varying the chromatic (color) contrast had little effect on reading performance. However,
when luminance contrast was very low, near – threshold, chromatic contrast sustained
reading rates of nearly 300 words per minute, almost as high as those found with high
luminance contrasts. On the other hand, for some low vision observers, text defined by
color contrast interfered with reading performance. Further investigations are planned to
determine why the reading of some low vision observers is adversely affected by color
contrast that is not accompanied by sufficient luminance contrast.
National Institute on Aging, with Mars Perceptrix Inc., to develop adjustable font
software for users with low vision. The software allows adjustment of many font parameters
in real-time, so that the user can see the impact of parameter adjustments on legibility
as it happens. The prototype software works, but evaluation using participants with low
vision suggested that font legibility could not be significantly improved above and beyond
that provided by highly evolved and readily available fonts such as TrueType Arial and
TrueType Times New Roman (Arditi, in press).
By comparing the letter confusions observed under wide and narrow inter-letter spacing,
they were able to determine that a large portion of the deterioration of legibility under
narrow spacing condition could be attributed to unique letter confusions which did not
occur when inter-letter spacing was wider. The cause of these unique letter confusions was
lateral interference (inhibition) from neighboring letters.
The human observers not only made mistakes in identifying closely packed small letters,
but they also misjudged the number of letters in the string. Using interlaced four-letter
and five-letter strings, Drs. Arditi and Liu demonstrated that human observers tended to
mistake more five-letter strings for four-letter strings when the inter-letter spacing was
narrowed. Typically, the observers would either omit one of the three letters in the
middle of the five-letter string, or combine two neighboring letters into a new letter.
The researchers used a computer simulation to demonstrate that optical blur of the eye
might have played an important role in this new aspect of the "crowding effect".
Visual acuity is measured as a function of the separation between the Landolt C and the
flanking bars. The inhibitory effect of the flanking bars is demonstrated as reductions of
visual acuity at certain separations. Drs. Liu and Arditi studied the effects of contrast
polarity by measuring contour interaction between a black C with four white bars, and
between a white C with four black bars. They found that features of different contrast
polarities were still engaged in inhibitory interaction, although the interaction appeared
to be weaker than that observed with features of the same contrast polarity. Therefore, a
simple linear receptive field model was not applicable to suprathreshold contour
interaction.
Flanking bars that were parallel exerted the strongest inhibition at the narrowest
separation between the Landolt C and the bars. At separations narrower than two gap
widths, the inhibition caused by a pair of parallel bars was stronger than that observed
when all four bars were present. The orthogonal bars only exerted moderate inhibition at
wider separations. It appeared that when four flanking bars were present, the orthogonal
bars alleviated the inhibitory effect of the parallel bars at narrower separations and
enhanced it at wider separations.
Such a deficit could affect reading performance by interfering with the
discriminability of letters having the same spatial frequency content but different
spatial phase spectra (i.e., mirror image letters like "b" vs. "d”).
However, they found that when letters were size-scaled to compensate for differences in
contrast sensitivity, the relationship between detection and identification performance
was the same in both the central and peripheral retinas. These results thus argue against
the hypothesis that the poorer reading performance outside the fovea is, somehow, due to
reduced letter discriminability that might occur secondarily to a loss of
peripheral-retina phase sensitivity.
http://www.lighthouse.org/research_legibility.htm
About Magic Speed Reading software
Speed reading techniques
|
Feature Highlights |
| > By using Speed reading software, you can improve
facilities of speed reading. You needn't practice special exercises; it
is just enough to read and periodical practice. Look at
free online speed reading trainings. All text
contain 50% of garbage. |
| > Remove 50% of letters
and you will read the text. Try to understand this simply idea and you speed
reading will up. Human mind read the words as china hieroglyph. You can
mix the letters and read the text. Try to
understand this simply idea and you speed reading will up. You can read the text
by groups of words. If you
strips the text you can also read the text. The
speed reading will by up if you wide the
span eyes. Use the full version of speed
reading software "Speed reading is
not magic". |
| > Habitually returning to what is already read, that
usually decreases the speed of reading, no longer happens. Reading each word
individually becomes unnecessary because skillful fast readers do not
individualize the text when reading at high speeds. |
| > You become accustomed to grasping a whole word or a
group of words at one glance. In this way you activate your peripheral vision
facilities. You study how to read without haste, because the program responds to
the speed you have chosen and does not react to your haste. The "Magic Speed
Reading" inclues 15 different computerized trainings. |
| > Speed reading is not magic :) |
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