Document Type


Date of Degree Completion

Winter 2017

Degree Name

Master of Science (MS)



Committee Chair

Terrence J. Schwartz

Second Committee Member

Susan Lonborg

Third Committee Member

Kara Gabriel


Research has shown that blue light can impact the circadian rhythm. Research has also suggested that use of electronic devices, such as computers and televisions that emit blue light before sleep, can negatively impact sleep quality. This research has led to the creation of computer software which lowers the levels of blue light in the evening to help with sleep. This study looked at the impact of wavelength filtering software on sleep onset, sleep duration and subjective alertness after morning waking of four college students. The college students were randomized into two groups and had the wavelength filtering software f.lux installed on their computer. Participants in the intervention group had their computer set to display 1900 K light 2 hours before bedtime for 7 days straight while the control group had their computer set to display 5000 K light. All participants were asked to complete the Pittsburgh Sleep Diary for 7 days straight. Participants in the 1900 K light condition on average had a longer sleep onset latency, shorter sleep duration and were subjectively less alert in the morning compared to the 5000 K light condition. However, the variability within groups made any differences in the means statistically insignificant. The majority of participants in both groups wanted to continue the software after the study. The low sample size prevented significant results from being formed. The study served as a pilot study to help direct future research on wavelength filtering software.