LCD螢幕高低調整策略及作業類型對於VDT使用者之效應

Effects of LCD Monitor Height Adjustment Strategy and Task Type on VDT User

吳水丕(S. P. Wu) ； 許芳榮(F. J. Hsu) ； 蔡武晃(W. H. Tsai) ； 張書瑀(S. Y. Chang)

《人因工程學刊》 9卷2期 (2007/12) Pp. 23-33

https://doi.org/10.6273/JES.2007.9(2).03

摘要

隨著電腦的家用化以及網際網路的普及，使得人類社會更加善用電腦科技，而在生活中須與電腦爲伍。然而，隨之而來的是操作VDT作業所產生的視覺與肌肉骨骼上的不舒適與疼痛，尤其是頭部與頸部的肌肉痠痛。而電腦螢幕配置是直接影響到視覺與肌肉骨骼問題的重要因素。位置較高的螢幕配置是視覺上的壓力來源，反之，位置較低的螢幕配置卻是肌肉骨骼上的壓力來源，也因此，如何能透過人因的介入策略，於各種不同的VDT作業下，在作業期間內，變換螢幕高度以獲得視覺與肌肉骨骼系統上的最舒適的感覺，便成爲可行的研究策略。
本研究共徵募12位受試者（6位爲男性，6位爲女性）來探討LCD螢幕高低調整策略對於VDT使用者之效應，研究變項包括九種螢幕高度變化策略及兩種作業型態，其中螢幕高度變化策略爲高到高、中到中、低到低、高到中、高到低、中到高、中到低、低到高、低到中，作業型態則包括輸入及閱讀兩種作業。衡量效標則包括身體傾斜角度、肌電訊號(EMG)以及肌肉疲勞知覺評量。本研究結果發現：(1)綜合各項衡量效標後發現，以低到中的螢幕調整策略爲最佳；(2)作業類型方面，以打字作業顯著比閱讀作業疲勞；(3)性別方面，均以女性較男性容易感到疲勞；(4)受試者之身體軀幹傾斜角度變化程度介於87到93度之間。整體而言，本研究結果証實，經由不同的螢幕高低調整策略可以使VDT使用者改變其姿勢，進而使其肌肉骨骼疲勞之問題獲得改善。

關鍵字

LCD ； VDT使用者 ； 螢幕高度調整排程策略 ； 人因介入

並列摘要

Eye discomfort and musculoskeletal illness are the main problems reported by visual display terminal (VDT) users. Computer monitor location is an important workstation design parameter and has been shown to directly affect posture and visual considerations. High monitor placement is considered a source of visual stress, whereas low placement is linked to musculoskeletal stress. Therefore, using ergonomic intervention to change computer monitor height for various input tasks is an important strategy to minimize both visual and musculoskeletal strains.
The aim of this study is to investigate LCD monitor height schedule strategy effects and different task types on visual and musculoskeletal fatigue. The participants in this study were 6 males and 6 females. The experimental period was 40 minutes. The independent variables were the schedule strategy with nine levels (high to high, middle to middle, low to low, high to middle, high to low, middle to high, middle to low, low to high, low to middle) and task type with two levels (data-entry task and reading task). The criterion variables included the critical fusion frequency (CFF), near point accommodation (NPA), electromyogram (EMG), viewing distance, thoracic bending, data-entry performance and visual and musculoskeletal strain subjective rating. The experimental period was extended to 40 minutes with a 20-minute interval used to adjust the monitor height. The results showed that: (1) The monitor position schedule, from low level to middle level, was the best. (2) The data-entry task produced more significant fatigue than the reading task. (3) Females felt more discomfort than males for all criteria. (4) The thoracic bending range was between 87° to 93°. In general, the work revealed that using ergonomic intervention to change the computer monitor height for various input tasks could change the VDT user's posture and reduce their visual and musculoskeletal discomfort.

並列關鍵字

LCD ； VDT users ； Adjustment monitor height strategy ； Ergonomic intervention