Experimental Research of Visual Performance with Differenet Optical Spectrum Light Sources

Abstract:

In order to determine the effect of different light source’s spectrum to a subjects’ visual performance, this experiment examined three fluorescent lamps with a colour temperature of 2700K, 4000K and 6500K and an incandescent lamp. The results were compared to the average recognition rate a “reference person” from different light sources. Experimental results show significant differences in the recognition rate from different optical spectrum light source and recognition rate value. We determined the best combination of ambient and chalkboard light source and propose avoiding combination for classroom lighting that is clearly inferior. This article provides selection reference for optimal classroom ambient and blackboard lighting. In recent years, the study of psychological and physiological effect of light has become one of the most important field in lighting research[1]. Studies has shown that different light spectrum could affect human circadian rhythm, body temperature and alertness, which directly affecting work efficiency and health[2]. The effects by classroom light spectrum on efficiency and health cannot be ignored, as the students are exposed to one particular lighting environment for extended periods of time. Through a systematic survey of classroom lighting in several universities in Chongqing and Chengdu, T5 fluorescent of high colour temperature about 6500K was the predominant choice for classroom general lighting as well as blackboard lighting. Many students complained that they tired easily at this colour temperature. In another study on classroom light source[3] students’ preference for colour temperature is not fixed but varies according to classroom’s function and illuminance level. It was insufficient to choose colour temperature of classroom lighting based on the results of the above questionnaire. We therefore chose and compared T5 fluorescent lamps of 2700K, 4000K and 6500K colour temperature on the visual performance and their effects on study efficiency, asthenopia and physiological rhythm. Due to space limitations this article only discusses the contrast experiment of visual performance.

• Periodical: Advanced Materials Research (Volumes 433-440)
• Pages: 6375-6383
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.433-440.6375
• Online since: January 2012
• Authors: Yong Hong Yan, Yang Guan, G. Lee Tang
• Keywords: Lighting, Recognition Rate, Reference Person, Spectrum, Visual Performance

References

[1] CIE, The influence of daylight and artificial light on diurnal and seasonal variations in humans - a bibliography, Publication CIE 139-2001, p.5.

DOI: 10.25039/tr.139.2001

[2] Yang Ming, Hao Yunxiang, Advances in Research on Phychobiological Effects of Light, China Illuminating Engineering Journal, vol. 11, Dec. 2000, pp.53-55 (In Chinese).

[3] Yan Yonghong, Research on Classroom healthy lighting based on photobiochemistry effects, Annual report of General Program of National Natural Science Foundation of China, Feb. 2009, pp.2-8. (In Chinese).

[4] Yan Yonghong, Guan Yang, Wang Ning, Zhang Xiaokang, Visual performance in a classroom with chalkboard illuminated by incandescent lighting and ambient lighting using T5 fluorescents, China Illuminating Engineering Journal, vol. 21, June 2010, pp.70-75.

[5] Pang Yunfan, Vision and Lighting, China Railway Publication, 1993, pp.256-257. (In Chinese).