Change of subjective and ophthalmological fatigue during long-term VDT work

Nowadays, since visual display terminals have been widely used in office for all day work, the research on the effect of long time work is still insufficient. In addition, the impact of LED light source for all day work is not clear. In this paper, the visual fatigue caused by long-term VDT work under LED luminaires with 300lux illuminance level was investigated through subjective questionnaire and ophthalmological parameters. The results showed that all the subjective symptoms got severer with increasing working time. Ophthalmological parameters of NPA, CFF, BUT, BCDVA and BCNVA were significantly influenced by working time under LED luminaires. The NPC, PRA and NRA were not significant influenced by working time under LED luminaires. The ophthalmological parameters NPC, CFF, BCDVA, BCNVA and PRA showed close relationship with the subjective state of visual fatigue.