Design And Implementation Of Strabismus Degree Measurement System Based On Virtual Reality And Eye Movement Tracking

Virtual reality is to use computer technology to simulate a multi perception space similar to real space.The technology can mobilize a number of human sensory organs to create a certain sense of immersion.By interacting with users,users can immerse themselves in the virtual world.Virtual reality is widely used in entertainment,military and education.Eye tracking technology is a technology that obtains the gaze point,gaze time,gaze number and other recording data from the eye movement track obtained by image acquisition,infrared sensor and computer.With the maturity of eye tracking technology,researchers began to introduce eye tracking technology in experiments to conduct a variety of information behavior research.Eye tracking technology can directly measure the participants’ gaze points,and is less susceptible to the subjective influence of the participants and researchers,thus making the results more reliable.Strabismus is when one eye is looking at a target and the other eye is not able to look at the target at the same time.It is biased and the axes of the eyes are not aligned.Among them,we will study the most common common common strabismus.No matter which eye the patient uses to focus on the target,the other eye will always be skewed,but the degree of strabismus is the same,which is a phenomenon involving both eyes.Based on the investigation and comparison of the relevant hardware devices and multiple virtual reality 3D engines available on the market,HTC vive virtual head display,ASEE VR eye tracker and unity3 d engine are determined to be used to realize the squint measurement system.The detailed method of hardware access to unity3 d is provided,and the conventional method of measuring squint degree in outpatient department of hospital is introduced.According to the analysis of the system requirements,the system is divided into three parts: slanting eye judgment module,calibration module and slanting degree measurement module.The relationship between the pupil center and the fixation point is explained,and the mathematical model provided by the calibration method is analyzed.The common method of judging the main eye in daily life is described.The process is simulated by controlling the left and right mirrors of VR glasses.The oblique direction and degree are calculated by using the perspective projection characteristics and the vector direction.The following details the implementation of the system;a series of required hardware equipment and software download and installation;the squint judgment module mainly introduces the virtual environment for judgment,the way to obtain the pupil coordinates in real time and the core code of the module implementation.The calibration module mainly introduces the virtual interface of calibration,implementation algorithm,and finally tests the calibration results.The core content of the squint data measurement module is to get the final result by measuring the angle degree of the gaze projection vector.