科技發展對我們的日常生活帶來許多樂趣和便利。高科技產品如手機、電腦、以及平板電腦等在現代人的生活中常扮演著至關重要的作用。而這些設備之電子顯示螢幕，則是成為與人之間資訊傳遞的主要界面之一。除了尺寸和解析度之外，螢幕顯示設備所發出的光也是人因工程設計中須考量的重要因素。過去研究顯示，當暴露在某些光照條件下時可以增加人的注意力、意識和警覺性，但是少有研究探討螢幕顯示的顏色對睡意的影響。因此, 本研究的主要目標是探討及評估在閱讀作業期間，三種不同文字和背景組合的螢幕顯示顏色設定，對於睡意的差別影響。

本研究招募了18位實驗參與者，他們分別在三種顏色組合（文字/背景: 黑/白-Bk/W，白/黑-W/Bk和白/藍-W/B）之一的閱讀條件下完成一小時的閱讀作業。三種測試之顏色組合涵蓋不同強度的藍光范圍波長，轉換為螢幕顯示的紅色、綠色和藍色（RGB）顏色組合後，黑色（R:0; G:0; B:0）所含藍光最少，白色（R:255; G:255; B:255）所含藍光最多，藍色(R:0; G:178; B:255）則將波長主要限定在470至480 nm之間。本研究測量的客觀指標包括腦電圖（EEG）、心率變異率（HRV）和臨界閃爍融合頻率（CFF），而主觀測量則包含卡羅林斯卡嗜睡量表（KSS）和閱讀測驗。

結果顯示，W/Bk可以增加睡意程度，Bk/W和W/B則可降低睡意程度，但W/B會導致眼睛疲勞。依照研究的結果推斷，在睡前可選擇W/Bk作為顏色組合來增加睡意，而選擇Bk/W於工作或學習時可以降低睡意。

The development of advanced technologies brings enjoyment and convenience to our daily life. The high-tech products such as mobile phone, computer, and tablet play an essential role in human life in this modern era. One of the main interaction interfaces between the person and these devices is the screen display. Besides the size and resolution of a screen display, the display light that emitted from the devices is also a critical consideration in the ergonomic design. Several studies have shown that certain light settings can increase concentration, awareness, and alertness of a person when exposed under these light conditions, but there are very few researches investigated the effect of direct light exposure emitting from the display devices on sleepiness. In the current study, the objective is to evaluate the effect of screen display light colors on sleepiness during the reading task with three different color combinations of texts and background colors.

Eighteen participants were recruited to participate in this study. They performed the reading task on-screen display for an hour. Reading conditions in this study consisted of three colors combinations (text/background: black/white-Bk/W, white/black-W/Bk and white/blue-W/B). The colors derived from the blue light wavelength range and converted into Red, Green, and Blue (RGB) colors. Black color set as the lowest blue light (R:0; G:0; B:0), white color set as the highest blue light (R:255; G:255; B:255), and the wavelength of blue color set from 470 to 480 nm (R:0; G:178; B:255). The Electroencephalography (EEG), Heart Rate Variability (HRV), and Critical Flicker Fusion Frequency (CFF) used as the objective measurements whereas Karolinska Sleepiness Scale (KSS) as the subjective measurement for measuring the sleepiness level and a questionnaire for reading performance.

The result showed that W/Bk could increase sleepiness level. Bk/W and W/B could reduce sleepiness level but W/B would cause eye-fatigue. The findings of this study inferred that selecting W/Bk as the color combinations before bedtime may increase sleepiness level whereas select Bk/W for working or studying may decrease sleepiness level.

摘要 i
ABSTRACT iii
CONTENTS v
LIST OF FIGURES vii
LIST OF TABLES ix
CHAPTER 1 INTRODUCTION 1
1.1 Background 1
1.2 Objective 4
1.3 Research Structure 5
CHAPTER 2 LITERATURE REVIEW 6
2.1 The Advancement of Technology 6
2.2 The Effects of Blue Light 7
2.3 Text-Background Color Combinations for Screen Reading 8
2.4 Benefits of Sleep 8
2.4.1 Measurement Tools 12
2.4.1.1 Karolinska Sleepiness Scale (KSS) 12
2.4.1.2 Electroencephalography (EEG) 13
2.4.1.3 Heart Rate Variability (HRV) 15
2.4.1.4 Critical Flicker Fusion Frequency (CFF) 17
CHAPTER 3 METHODOLOGY 19
3.1 Experiment Design 19
3.2 Research Participant 23
3.3 Experiment Site 24
3.4 Experiment Apparatus 25
3.4.1 Desktop Computer 25
3.4.2 Measurement of EEG 25
3.4.3 Measurement of HRV 31
3.5 Experiment Procedure 32
3.6 Research Analysis 35
3.6.1 EEG Analysis 35
3.6.2 HRV Analysis 36
3.6.3 Analysis of Result 36
CHAPTER 4 RESULT 37
4.1 Participants’ General Information 37
4.2 KSS Analysis 38
4.3 EEG Analysis 40
4.3.1 EEG Stage 40
4.3.2 EEG Region 41
4.4 HRV Analysis 44
4.5 CFF Analysis 45
4.6 Between-Subjects Analysis 47
CHAPTER 5 DISCUSSION 49
5.1 Color Combinations before Bedtime 50
5.2 Color Combinations for Working/Studying 51
CHAPTER 6 CONCLUSION 53
REFERENCES 55

A Recent World Sleep Pattern Ranking Reveals That Indians Are Sleep Deprived Compared To Countries Like New Zealand.(2017,March 17).
https://www.indiatimes.com/health/healthyliving/a-recent-world-sleep-pattern-ranking-reveals-that-indians-are-sleep-deprived-compared-to-countries-like-new-zealand-273637.html
Ahsberg, E. (1998).Perceived Fatigue Related to Work. University of Stockholm, Department of Psychology, Sweden, ISBN 91-7153-830-5.
AJ Camm, M Malik, JT Bigger, G Breithardt. (1996). TASK FORCE OF ESC AND NASPE. Heart rate variability: Standards of measurement, physiological interpretation, and clinical use. Circulation 1996;93(5):1043–1065.
Alfred J. Lewy. (1983). Effects of Light on Human Melatonin Production and the Human Circadian System.
American Academy of Pediatrics Guideline. (2016,October 21).
http://edition.cnn.com/2016/10/21/health/screen-time-media-rules-children-aap/index.html
Andrew Morley & Lizzie Hill. (2016). 10-20 system EEG Placement. European Respiratory Society.
Anja Zorko, Snježana Ivančić Valenko, Mario Tomiša, Damira Keček. (2017). The Impact of The Text and Background Color on The Screen Reading Experience.
Ann Williamson, David A. Lombardi, Simon Folkard, JaneStutts, Theodore K.Courtney, Jennie L.Connor. (2009). The link between fatigue and safety.
Antoine U Viola, Lynette M James, Luc JM Schlangen and Derk-Jan Dijk. (2008). Blue-enriched white light in the workplace improves self-reported alertness, performance and sleep quality. Scandinavian Journal of Work, Environment & Health:Vol. 34, No. 4 (August 2008), pp. 297-306.
B. Plitnick, MG Figueiro, B. Wood, MS Rea. (2009). The Effects of Red and Blue Light on Alertness and Mood at Night. Volume: 42 issue: 4, page(s): 449-458.
Healthy Sleep (The Division of Sleep Medicine at Harvard Medical School).
http://healthysleep.med.harvard.edu/
BF Godley, FA Shamsi, FQ Liang, Stuart G. Jarrett, Sallyanne Davies, Mike Boulton. (2005). Blue Light Induces Mitochondrial DNA Damage and Free Radical Production in Epithelial Cells.
Bharathi.C.K, Pothi Reddy K. (2015). Measuring Critical Flicker Fusion Frequency in Human Eye by Utilizing Sound Card of the Computer as DAC. International Journal for Research in Applied Science & Engineering Technology: Volume 3, Special Issue-1, May 2015.
Chiuhsiang Joe Lin, Wen-Yang Feng,Chin-Jung Chao, Feng-Yi Tseng. (2007). Effects of VDT Workstation Lighting Conditions on Operator Visual Workload.
Christos Papadelis, Chrysoula Kourtidou-Papadeli, Panagiotis D.Bamidis,Ioanna Chouvarda,D.Koufogiannis,E.Bekiaris,NikosMaglaveras. (2006). Indicators of Sleepiness in an ambulatory EEG study of night driving.
Computer Vision Syndrome (Digital Eye Strain).
https://opto.ca/health-library/computer-vision-syndrome-digital-eye-strain
Costa G. (2003). Shift work and occupational medicine. Occup Med 2003;53:83–88.
Deubel, P. (2003). An investigation of behaviorist and cognitive approaches to instructional multimedia design. Journal of Educational Multimedia and hypermedia, 12(1), 63-90.
De Gennaro, L., Vecchio, F., Ferrara, M., Curcio, G., Rossini, P.M., Babiloni, C. (2005). Antero-posterior functional coupling at sleep onset: changes as a function of increased sleep pressure. Brain Res. Bull. 65, 133–140.
Dillon, A. (1992). Reading from paper versus screens: A critical review of the empirical literature. Ergonomics, 35(10), 1297–1326.
Emmanouil Michail, Athina Kokonozi, Ioanna Chouvarda, Nicos Maglaveras. (2008). EEG and HRV markers of sleepiness and loss of control during car driving.
Fossum IN, Nordnes LT, Storemark SS, Bjorn Bjorvatn, Stale Pallesen. (2014). The association between use of electronic media in bed before going to sleep and insomnia symptoms, daytime sleepiness, morningness, and chronotype.
Furman G, Baharav A, Cahan C, AkselRod S. (2008). Early Detection of Falling Asleep at the Wheel: A Heart Rate Variability Approach. In Computers in Cardiology.Sept. 2008; 1109-1112.
Goran Kecklund, T Åkerstedt. Ergonomics. (1993). Sleepiness in long distance truck driving: an ambulatory EEG study of night driving.
Gary G. Berntson, J. Thomas Bigger JR., Dwain L. Eckberg, Paul Grossman, Peter G.Kaufmann, Marek Malik, Haikady N.Nagaraja, Stephen W.Porges, J.Philip Saul, Peter H. Stone, Maurots W. Van Der Molen. (1997). Heart rate variability: origins, methods, and interpretive caveats, psychophysiology, vol. 34(6), pp.623-648, November.
Gianluca Tosini,Ian Ferguson, Kazuo Tsubota. (2016). Effects of Blue Light on the Circadian System and Eye Physiology.2016; 22: 61–72.
Giovanni Vecchiato,Laura Astolfi,Fabrizio De VicoFallani,Febo Cincotti,Donatella Mattia,Serenella Salinari,Ramon Soranzo,Fabio Babiloni.(2010).Changesin Brain Activity During the Observation of TV Commercials by Using EEG, GSR and HR Measurements. June 2010, Volume 23, Issue 2, pp 165–1791.
Gradisar M, Wolfson AR, Harvey AG, Lauren Hale, Russell Rosenberg,Charles A. Czeisler. (2013). The sleep and technology use of Americans: findings from the National Sleep Foundation’s 2011 Sleep in America poll. J Clin Sleep Med 2013;9:1291–9.
Hall, R. H., & Hanna, P. (2004). Web Text-Background Color. Behavior & Information Technology, 23(3), 183–195.
Hanho Jeong. (2010). A comparison of the influence of electronic books and paper books on reading comprehension, eye fatigue, and perception.
Heikki V. Huikuri, Kenneth M.Kessler, Elisabeth Terracall, AgustinCastellanos, Markku K.Linnaluoto, Robert J.Myerburg. (1990). Reproducibility and circadian Rhythm of Heart Rate Variability in Healthy Subjects: volume 65, issue 5, page 391-393.
Ingre M, Kecklund G, Akerstedt T, Kecklund L. (2004). Variation in sleepiness during early morning shifts: a mixed model approach to an experimental field study of train drivers. Chronobiol Int. 2004;21(6):973-90.
Isadewa, Bagas. (2011). Ekstraksi Fitur Sinyal Elektroensefalograf (EEG) untuk Identifikasi Unspoken-Speech Menggunakan EEGLAB.
J. Satheesh Kumar & P.Bhuvaneswari.(2012).Analysis of Electroencephalography (EEG) Signals and Its Categorization–A Study.
Jeffrey M. Ellenbogen. (2005). Cognitive benefits of sleep and their loss due to sleep deprivation. April 12,2005;64(7).
John M.Sullivan. (2008). Visual Fatigue and the Driver. The University of Michigan Transportation Research Institute Ann Arbor, Michigan 48109-2150 U.S.A.
Jonathan B. Lin; Blair W. Gerratt; Carl J. Bassi; Rajendra S. Apte. (2017). Short-Wavelength Light-Blocking Eyeglasses Attenuate Symptoms of Eye Fatigue. Investigative Ophthalmology & Visual Science January 2017, Vol.58, 442-447. doi:10.1167/iovs.16-2066.
Kenneth Wright JR, Pietro Badia, Bryan Myers, Steven Plenzler. (1997). Combination of bright light and caffeine as a countermeasure for impaired alertness and performance during extended sleep deprivation.
Kiymik, M.K., Akin, M., Subasi, A. (2004). Automatic Recognition of Alertness Level by Using Wavelet Transform and Artificial Neural Network. Journal of Neuroscience Method, 139, 231–240.
KPCB’s Internet Trends 2015 Report Outlines a Bright Future for the Internet.(2015,December 15).
https://www.digitalrealty.com/blog/kpcbs-internet-trends-2015-report-outlines-a-bright-future-for-the-internet/
Lars Torsvall,Torbjöurn Akerstedt,Katja Gillander, Anders Knutsson. (1989). Sleep on the Night Shift: 24-Hour EEG Monitoring of Spontaneous Sleep/Wake Behavior.
Malik, M. & Camm, A. J. (1995). Heart Rate Variability (Futura, Armonk, NY).
Malmivuo J, Plonsey R. (1995). Bioelectromagnetism. Oxford/New York: Oxford Univ. Press.
Mani Kumar Tellamekala,Mohammad Rafi. (2016). Fragrance Effect on Beta Band Oscillations of Primary Visual and Prefrontal Cortices for Reading Tasks.
Mark R. Pressman and June M. Fry. (1989). Relationship of Autonomic Nervous System Activity to Daytime Sleepiness and Prior Sleep.
Massimo Greco, Natale Stucchi, Daniele Zavagno, Barbara Marino. (2008). On the Portability of Computer-Generated Presentations: The Effect of Text-Background Color Combinations on Text Legibility.
Mindell & Owens. (2010). Clinical Guide to Pediatric Sleep: Diagnosis and Management of Sleep Problems (Lippincott Williams & Wilkins, 2nd ed. 2010) p. 258.
Mika P Tarvainen, Niskanen JP, Lipponen JA, Ranta-aho P. O, Karjalainen P. A. (2008). Kubios HRV-a software for advanced heart rate variability analysis.
Milos Matousek and Ingemar Petersen. (1983). A Method for Assessing Alertness Fluctuations From EEG Spectra.
Mobile Usage Statistics: Key Facts and Findings for Publishers. (2016, March 18).
https://blog.ezoic.com/mobile-usage-statistics-key-facts-and-findings-for-publishers/
Murch, G. M. (1987). Color graphics: Blessing or bally-hoo? The visual channel in Baecker, R., M. & Buxton, W. A. S. (Eds.) Readings in Human-Computer Interaction: A Multidisciplinary Approach Burlington, MA: Morgan Kaufmann Publications, 333-341.
National Sleep Foundation Recommends New Sleep Times.(2015).
https://sleepfoundation.org/press-release/national-sleep-foundation-recommends-new-sleep-times/page/0/1
Nur Indria Lisdiani & Yassierli. (2012). Blue Light Exposure Improves Awareness during Monotonous Activities at Night.
Pace, B.J. (1984). Color combinations and contrast reversals on visual display units. In Proceedings of the Human Factors Society 28th Annual Meetining,. M. J. Alluisi, S. de Groot, and E. A. Alluisi. Eds. Human Factors Society, Santa Monica; Calif., pp. 326-331.
Ramadan, M., Mohamed, A., El-Hariry, H. (2010). Effects of cathode ray tube display formats on quality-assurance auditor’s perfor-mance. Human Factors and Ergonomics in Manufacturing and Service Industries 20, 61–72.
Reyner LA, Horne JA. (1998). Falling asleep whilst driving: are drivers aware of prior sleepiness? Int J Legal Med 1998;111(3):120-3.
Rivera, M. (2013). Monitoring of Micro-sleep and Sleepiness for the Drivers Using EEG Signal.
Russell Lawton. (1994). Airframe Icing and Captain’s Improper Use of Autoflight System Result in Stall and Loss of Control of Commuter Airplane.
S Lehrl, K Gerstmeyer, JH Jacob, H Frieling, A.W. Henekl,R. Meyrer, J. Wiltfang, J. Kornhuber,S. Bleich. (2007). Blue light improves cognitive performance.
S Porcu, A Bellatreccia, M Ferrara, M. Casagrande. (1998). Sleepiness, alertness and performance during a laboratory simulation of an acute shift of the wake-sleep cycle.
Samuel O Adeosun, Sola O ASA, Oladipo O BabaLola,Moses A Akanmu. (2008). Effects of night-reading on daytime sleepiness, sleep quality and academic performance of undergraduate pharmacy students in Nigeria.
Sarah Laxhmi Chellappa, Roland Steiner, Peter Blattner, Peter Oelhafen,Thomas Götz,Christian Cajochen. (2011). Non-Visual Effects of Light on Melatonin, Alertness and Cognitive Performance: Can Blue-Enriched Light Keep Us Alert?
Schier, M. (1999). Changes in EEG Alpha Power during Simulated Driving: a demonstration. International Journal Psyshophysiologi, 37(2), 155-156.
Sebastian Olbrich,Christoph Mulert,Susanne Karch,Maja Trenner,Gregor Leicht, Oliver Pogarell,Ulrich Hegerl. (2009). EEG-vigilance and BOLD effect during simultaneous EEG/fMRI measurement. Volume 45, Issue 2, 1 April 2009, Pages 319-332.
Shinar Z, Akselrod S, Dagan Y, Baharav A. (2006). Autonomic Changes During Wake-Sleep Transition: A Heart Rate Variability Based Approach. Auton Neurosci 2006;130:17-27.
Smartphone, computer, or tablet? 36% of Americans own all of three. (2015, November 25).
http://www.pewresearch.org/fact-tank/2015/11/25/device-ownership/
Steven W. Lockley,Erin E. Evans,Frank A.J.L. Scheer,George C. Brainard,Charles A. Czeisler,Daniel Aeschbach. (2006). Short-Wavelength Sensitivity for the Direct Effects of Light on Alertness, Vigilance, and the Waking Electroencephalogram in Humans.
Strijkstra, A.M., Beersma, D.G.M., Drayer, B., Halbesma, N., Daan, S., (2003). Subjective sleepiness correlates negatively with global alpha (8–12 Hz) and positively with central frontal theta (4–8 Hz) frequencies in the human resting awake electroencephalogram. Neurosci. Lett. 340, 17–20.
Susumu Saito, Midori Sotoyama, Shin Saito, and Sasitorn Taptagapornc. (1994). Physiological Indices of Visual Fatigue due to VDT Operation: Pupillary Reflexes and Accommodative Responses.
Tal Oron-Gilad, Adi Ronen, David Shinar. (2008). Alertness Maintaining Tasks (AMTs) While Driving.
Technology Device Ownership: 2015. (2015, October 29).
http://www.pewinternet.org/2015/10/29/technology-device-ownership-2015/
The Demographics of Device Ownership. (2015, October 2009).
http://www.pewinternet.org/2015/10/29/the-demographics-of-device-ownership/
Trockel, M. T, Barnes, M. D, Egget, D. L. (2000). Health-Related Variables and Academic Performance among First-Year College Students: Implications for Sleep and Other Behaviors. Journal of American College Health. 49(3): 125-131.
Video Display Terminal (VDT) Guidelines of Occupational Safety & Health Administration (OSHA, 1997).
W Janig. (1989). Autonomic Nervous System.Human Physiology. pp 333-370.
Walker MP, Brakefield T, Hobson JA, Stickgold R. (2003). Dissociable stages of human memory consolidation and reconsolidation. Nature 2003;425:616–620.
Wang, A.H., & Chen, M.T. (2000). Effects of polarity and luminance contrast on visual performance and VDT display quality. International Journal of Industrial Ergonomics, 25, 415– 421.
Wang, A., Fang, J. and Chen, C. (2003). Effects of VDT Leading-Display Design on Visual Performance of Users in Handling Static and Dynamic Display Information Dual-Tasks. International Journal of Industrial Ergonomics, 32, 93- 104.
Wavelength to RGB and HEX Calculator (Dr. Dan Bruton, Stephen F. Austin State University)
http://lsrtools.1apps.com/wavetorgb/index.asp?wavelength=125
Wen-Chien Liang, John Yuan, D.C. Sun, Ming Han Lin. (2007). Variation in Physiological Parameters Before and After an Indoor Simulated Driving Task: Effect of Exercise Break , 2007 International Conference on Gerontic Technology and Service Management (ICGTSM), Nantou County, Taiwan, March-26-2007.
What Are Sleep Deprivation and Deficiency? (National Heart, Lung, and Blood Institute (NHLBI)
https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency
What is an accident at work? Occupational Safety and Health Administration (OSHA) in Europe. (2012).
http://osha.europa.eu/en/faq/faq1/what-is-an-accident-at-work
Why Sleep Is Important: Importance of sleep.
http://www.apa.org/topics/sleep/index.aspx
William E. Kelly, Kathryn E. Kelly, Robert C. Clanton. (2001). The Relationship between Sleep Length and Grade-Point Average among College Students.