Opto-Guard: Non-invasive System of Continuous User Assurance of Keeping the Optimal Distance of the Eyes from the Computer Screen

Computer related health problems, reported to affect up to 90% of users, could be prevented to a very large extent. The knowledge of the risk factors and the timely adoption of measures are exclusively the responsibility of the user, involving a multidirectional approach to mitigate the effects of a prolonged improper position in front of the computer. For this matter, American Optometric Association states that the wrong positioning while performing computer tasks is the major contributing factor to digital screen-related vision problems. As a solution, the paper presents a warden system proposal that uses the computer's web camera to measure the distance at which the user is from its screen. The particularity consists in the video measurement method the system uses, calculating the distance without a reference, increasing the measurement resolution and implicitly the accuracy of the distance measurement. The range of interest for which tests were conducted is between 40 and 63 cm proximity, being the visual depth considered most comfortable. In addition, the system advances a visual warning in the event that the user is not in the visual safety area. The advantage of the Opto-Guard system is that it does not require additional equipment or the user intervention to function, only camera calibration being necessary once.