Wearable Sensors for Measurement of Viewing Behavior, Light Exposure, and Sleep

Abstract

The purpose of this study was to compare two wearable sensors to each other and to a questionnaire in an adult population. For one week, participants aged 29.2 ± 5.5 years (n = 25) simultaneously wore a Clouclip, a spectacle-mounted device that records viewing distance and illuminance, and an Actiwatch, a wrist-worn device that measures illuminance and activity. Participants maintained a daily log of activities and completed an activity questionnaire. Objective measures of time outdoors, near (10–< 60 cm) and intermediate (60–100 cm) viewing, and sleep duration were assessed with respect to the daily log and questionnaire. Findings showed that time outdoors per day from the questionnaire (3.2 ± 0.3 h) was significantly greater than the Clouclip (0.9 ± 0.8 h) and Actiwatch (0.7 ± 0.1 h, p < 0.001 for both). Illuminance from the Actiwatch was systematically lower than the Clouclip. Daily near viewing duration was similar between the questionnaire (5.7 ± 0.6 h) and Clouclip (6.1 ± 0.4 h, p = 0.76), while duration of intermediate viewing was significantly different between methods (p < 0.001). In conclusion, self-reported time outdoors and viewing behaviors were different than objective measures. The Actiwatch and Clouclip are valuable tools for studying temporal patterns of behavioral factors such as near work, light exposure, and sleep.

Objective quantification of viewing behaviours during printed and electronic tasks in emmetropic and myopic ultra‐Orthodox Jewish men

“…Viewing distance was measured objectively using a Clouclip (http://clouclip.com). This was mounted on the right temple of the participant's habitual spectacle frame or a frame provided with plano lenses 34 . The Clouclip is a lightweight Bluetooth spectacle‐mounted device that measures viewing distance every 5 s using infrared time‐of‐flight technology.…”

“…This was mounted on the right temple of the participant's habitual spectacle frame or a frame provided with plano lenses. 34 The Clouclip is a lightweight Bluetooth spectacle-mounted device that measures viewing distance every 5 s using infrared time-of-flight technology. The tracking beam diameter is 25° and is angled 10° inferiorly and has been validated for distances of 10-99 cm.…”

Verification, analytical validation and clinical validation (V3) of wearable dosimeters and light loggers

“…Systematic in-laboratory comparisons of the optical performance of light-logging sensors show large differences in their ability to capture biologically relevant light in commonly used sensors. 25,[34][35][36][37][38][39][40] A recent comprehensive review on light-dosimetry studies showed that in the published literature, there is a large variability of parameters used in these studies. 20 The authors found a total of 25 unique device types used in the literature.…”

“…Systematic in-laboratory comparisons of the optical performance of light-logging sensors show large differences in their ability to capture biologically relevant light in commonly used sensors. 25 , 34 – 40 …”

Objective Quantification and Topographic Dioptric Demand of Near-Work

“… 13 Current wearable devices estimating near-work in real-life settings using single time-of-flight sensors have found a mismatch between objective and subjective reports on near-work. 14 , 15 However, single time-of-flight sensors only measure object distances at a limited range and within a narrow field angle (much smaller than the field of fixations). These time-of-flight sensors also introduce inaccuracy at best and systematic biases at worst because they do not take into account the direction of gaze.…”