Visual Demand and Acuity Reserve of Chinese versus English Newspapers

Abstract

SIGNIFICANCE This study suggests that Chinese newspaper characters are more legible than English newspaper letters. Characters in Chinese newspapers have higher acuity reserve than English newspapers. PURPOSE The purpose of this study was to evaluate visual demand and acuity reserve for Chinese newspapers in comparison with published data on U.S. newspapers. METHODS The test distances for visual acuity in Chinese clinical studies were reviewed systematically. Characters from different sections of newspapers printed in simplified Chinese were evaluated. The character height, frequency, and visual demand and acuity reserve of each newspaper section were determined for Chinese characters of the six different levels of complexity. RESULTS More than 70% of Chinese clinical studies measure near visual acuity at either 33 or 40 cm. The height of Chinese characters ranged from 1.95 to 3.28 mm across different sections of five newspapers compared with 1.0 to 2.0 mm for English letters. The frequency of Chinese characters from least to most complex ranged from 7 to 34% across 12 sections of one Chinese newspaper. The angular threshold across the six complexity levels of Chinese characters ranged from 4.62 to 5.93 arcmin (0.54 to 0.69 mm at 40-cm reading distance) with a weighted angular threshold of 5.18 arcmin compared with 3.37 arcmin (0.39 mm) for the English letters. For Chinese newspapers, at 40-cm reading distance, the acuity reserve for the smallest and largest median size was 3.55 and 4.61, respectively. CONCLUSIONS Chinese characters are larger than English characters in all newspaper sections newspapers by a factor of 1.60 to 2.34. Given that Chinese characters need to be 1.54 times larger than English letters to provide the same acuity reserve, on average, Chinese newspapers are more legible than U.S. English newspapers.

BCLA CLEAR – Contact lens optics

“…Charts based on logMAR principles are preferred, be the reduced-size Bailey--Lovie and ETDRS charts or charts containing lower case words that follow a logarithmic progression such as Bailey-Lovie word reading charts [155] or the Minnesota Low-Vision Reading Test (MNRead) [156] (see Section 5.4). Testing of intermediate visual acuity may be conducted at 100, 80 or 66 cm and near visual acuity at 40 or 33 cm, depending on the regulatory standards and practice for a given country [157]. These correspond to vergence ranges from -1.00 D to -3.00 D.…”

Visual Outcomes and Patient Satisfaction of Trifocal or Trifocal Toric IOLs in Chinese Cataract Patients: Focus on Near Vision at 33 cm

“…Secondly, due to the nature of Chinese characters, which need to be 1.54 times larger than English letters to provide equivalent acuity reserve, individuals tend to be closer to books or newspapers. 8 A study evaluating the impact of viewing distance on normal Chinese reading indicated that 35 cm was the optimal viewing distance. 9 The study revealed that the maximum mean reading rate of 494 characters per minute occurred at approximately 35.0 cm, corresponding to an optimal visual angle (horizontal and vertical) of 0.5 degrees for each character.…”

Analysis of Daily Visual Habits in a Presbyopic Population

“…Specifically, mean preferred reading distances between 32 cm and 41 cm has been reported in patients undergoing cataract surgery implanted with different modalities of multifocal IOL [ 11 – 14 ]. Furthermore, it has been demonstrated that there are some differences in visual demands and preferences among Asiatic and European individuals, being this another factor to consider [ 18 , 19 ]. Recently, a new device capturing information about daily activities, working visual distances and illumination conditions has been developed (Vivior Monitor system, Vivior AG, Zürich, Switzerland), which can be especially useful for evaluating visual requirements and habits before and after cataract surgery with implantation of PC IOLs.…”