König Mirjam, Haensel Claudia, Jaschinski Wolfgang
Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany.
Clin Exp Optom. 2015 May;98(3):244-53. doi: 10.1111/cxo.12274.
This study intended to measure the near and far points of clear vision as a function of the inclination of the line of sight with comfortable head posture. Measurements with different lenses for presbyopic correction were made to suggest comfortable positions of the monitor for computer work.
An 'inclined optometer' was built, including a concave mirror to shift a visual target of constant angular size from near to infinity (proposed by Reiner). The optometer could be inclined vertically from horizontal to 50 degrees downward to vary the inclination of the line of sight. Measurements were made with a comfortable head position adjusted on a headrest.
The near and far points were plotted both in the unit one/metre as a function of eye inclination (optometric diagram) and also as positions from the eyes in workspace co-ordinates (workplace diagram). First, individual examples of plots of the vertical zones of clear vision at the workplace are shown. Second, the group mean data of 22 observers with newly prescribed lenses showed that the vertical zones of clear vision for general purpose progressive addition lenses (PALs) reach infinity and are flatter, while computer vision PALs lead to more steep vertical zones ending at intermediate distances. Third, the mean results of three samples from our laboratory were compared with respect to general purpose PALs, which are most frequently used by presbyopic people.
The diagrams of the vertical zones of clear vision for different spectacles provide information on the ergonomic vertical position of computer monitors for clear vision with a comfortable head position. The grand mean of general purpose PALs suggests that the upper edge of the monitor should be at least approximately 15 cm below eye level at a typical viewing distance of approximately 75 cm. Higher monitor positions are possible with computer vision PALs.
本研究旨在测量在舒适头部姿势下，清晰视觉的近点和远点与视线倾斜度之间的关系。使用不同的老花矫正镜片进行测量，以确定计算机工作时显示器的舒适位置。
构建了一台“倾斜验光仪”，其中包括一个凹面镜，用于将恒定视角大小的视觉目标从近处移至无穷远（由赖纳提出）。该验光仪可从水平方向垂直向下倾斜至50度，以改变视线的倾斜度。测量时，头部置于头枕上，保持舒适的位置。
近点和远点既以每米的单位作为眼睛倾斜度的函数绘制（验光图），也以工作空间坐标中相对于眼睛的位置绘制（工作场所图）。首先，展示了工作场所清晰视觉垂直区域图的个别示例。其次，22名新配镜观察者的组平均数据表明，通用渐进多焦点镜片（PAL）的清晰视觉垂直区域可达无穷远且更平缓，而计算机视觉PAL则导致更陡峭的垂直区域，在中间距离处结束。第三，将我们实验室三个样本关于通用PAL的平均结果进行了比较，通用PAL是老花眼患者最常用的。
不同眼镜的清晰视觉垂直区域图提供了有关计算机显示器人体工程学垂直位置的信息，以便在舒适头部姿势下实现清晰视觉。通用PAL的总体平均值表明，在典型观看距离约75厘米时，显示器的上边缘应至少比眼睛水平低约15厘米。使用计算机视觉PAL时，可以将显示器放置在更高的位置。
