为研究不同道路监控补光灯对驾驶员眩光的影响程度,挑选10名视力正常受试者夜晚驾车经过城市、郊区、高速3种不同环境路段,使用照度计测量不同路段补光灯及补光灯环境照度,采用Tobii Pro Glasses 2眼动仪获取眼动特征数据,分析驾驶员瞳...为研究不同道路监控补光灯对驾驶员眩光的影响程度,挑选10名视力正常受试者夜晚驾车经过城市、郊区、高速3种不同环境路段,使用照度计测量不同路段补光灯及补光灯环境照度,采用Tobii Pro Glasses 2眼动仪获取眼动特征数据,分析驾驶员瞳孔直径变化程度及瞳孔中心位移变化。研究结果表明:驾驶员在不同道路监控补光灯照明刺激下,人眼运动会发生不同程度变化。郊区道路瞳孔直径变化最大可达32%左右,是城市道路及高速道路的3倍左右。郊区道路监控补光灯照度以及补光灯环境照度差距明显,增大驾驶员暗适应时间,在3 s内瞳孔直径未能恢复正常,造成视物不清。同时在郊区道路驾驶员瞳孔中心位置偏移至视角范围为5°~220°的边缘区域远离中央窝区,造成视野模糊。研究结果可为驾驶员夜间安全驾驶提供数据支撑及应对措施。展开更多
Human eye detection has become an area of interest in the field of computer vision with an extensive range of applications in human-computer interaction,disease diagnosis,and psychological and physiological studies.Ga...Human eye detection has become an area of interest in the field of computer vision with an extensive range of applications in human-computer interaction,disease diagnosis,and psychological and physiological studies.Gaze-tracking systems are an important research topic in the human-computer interaction field.As one of the core modules of the head-mounted gaze-tracking system,pupil positioning affects the accuracy and stability of the system.By tracking eye movements to better locate the center of the pupil,this paper proposes a method for pupil positioning based on the starburst model.The method uses vertical and horizontal coordinate integral projections in the rectangular region of the human eye for accurate positioning and applies a linear interpolation method that is based on a circular model to the reflections in the human eye.In this paper,we propose a method for detecting the feature points of the pupil edge based on the starburst model,which clusters feature points and uses the RANdom SAmple Consensus(RANSAC)algorithm to perform ellipse fitting of the pupil edge to accurately locate the pupil center.Our experimental results show that the algorithm has higher precision,higher efficiency and more robustness than other algorithms and excellent accuracy even when the image of the pupil is incomplete.展开更多
AIM: To investigate the independent factors associated with photic phenomena in patients implanted with refractive,rotationally asymmetric,multifocal intraocular lenses(MIOLs).METHODS: Thirty-four eyes of 34 patie...AIM: To investigate the independent factors associated with photic phenomena in patients implanted with refractive,rotationally asymmetric,multifocal intraocular lenses(MIOLs).METHODS: Thirty-four eyes of 34 patients who underwent unilateral cataract surgery,followed by implantation of rotationally asymmetric MIOLs were included.Distance and near visual acuity outcomes,intraocular aberrations,preferred reading distances,preoperative and postoperative refractive errors,mesopic and photopic pupil diameters,and the mesopic and photopic kappa angles were assessed.Patients were also administered a satisfaction survey.Photic phenomena were graded by questionnaire.Independent-related factors were identified by correlation and bivariate logistic regression analyses.RESULTS: The distance from the photopic to the mesopic pupil center(pupil center shift) was significantly associated with glare/halo symptoms [odds ratio(OR)=2.065,95% confidence interval(CI)=0.916-4.679,P=0.006] and night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007).The preoperative photopic angle kappa was significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041).The photopic angle kappa was also significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041) and with night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007) in patients implanted with rotationally asymmetric MIOLs.CONCLUSION: A large pupil center shift and misalignment between the visual and pupillary axis(angle kappa)may play a role in the occurrence of photic phenomena after implantation of rotationally asymmetric MIOLs.展开更多
文摘为研究不同道路监控补光灯对驾驶员眩光的影响程度,挑选10名视力正常受试者夜晚驾车经过城市、郊区、高速3种不同环境路段,使用照度计测量不同路段补光灯及补光灯环境照度,采用Tobii Pro Glasses 2眼动仪获取眼动特征数据,分析驾驶员瞳孔直径变化程度及瞳孔中心位移变化。研究结果表明:驾驶员在不同道路监控补光灯照明刺激下,人眼运动会发生不同程度变化。郊区道路瞳孔直径变化最大可达32%左右,是城市道路及高速道路的3倍左右。郊区道路监控补光灯照度以及补光灯环境照度差距明显,增大驾驶员暗适应时间,在3 s内瞳孔直径未能恢复正常,造成视物不清。同时在郊区道路驾驶员瞳孔中心位置偏移至视角范围为5°~220°的边缘区域远离中央窝区,造成视野模糊。研究结果可为驾驶员夜间安全驾驶提供数据支撑及应对措施。
基金This research was funded by the Science and Technology Support Plan Project of Hebei Province(grant numbers 17210803D and 19273703D)the Science and Technology Spark Project of the Hebei Seismological Bureau(grant number DZ20180402056)+1 种基金the Education Department of Hebei Province(grant number QN2018095)the Polytechnic College of Hebei University of Science and Technology.
文摘Human eye detection has become an area of interest in the field of computer vision with an extensive range of applications in human-computer interaction,disease diagnosis,and psychological and physiological studies.Gaze-tracking systems are an important research topic in the human-computer interaction field.As one of the core modules of the head-mounted gaze-tracking system,pupil positioning affects the accuracy and stability of the system.By tracking eye movements to better locate the center of the pupil,this paper proposes a method for pupil positioning based on the starburst model.The method uses vertical and horizontal coordinate integral projections in the rectangular region of the human eye for accurate positioning and applies a linear interpolation method that is based on a circular model to the reflections in the human eye.In this paper,we propose a method for detecting the feature points of the pupil edge based on the starburst model,which clusters feature points and uses the RANdom SAmple Consensus(RANSAC)algorithm to perform ellipse fitting of the pupil edge to accurately locate the pupil center.Our experimental results show that the algorithm has higher precision,higher efficiency and more robustness than other algorithms and excellent accuracy even when the image of the pupil is incomplete.
文摘AIM: To investigate the independent factors associated with photic phenomena in patients implanted with refractive,rotationally asymmetric,multifocal intraocular lenses(MIOLs).METHODS: Thirty-four eyes of 34 patients who underwent unilateral cataract surgery,followed by implantation of rotationally asymmetric MIOLs were included.Distance and near visual acuity outcomes,intraocular aberrations,preferred reading distances,preoperative and postoperative refractive errors,mesopic and photopic pupil diameters,and the mesopic and photopic kappa angles were assessed.Patients were also administered a satisfaction survey.Photic phenomena were graded by questionnaire.Independent-related factors were identified by correlation and bivariate logistic regression analyses.RESULTS: The distance from the photopic to the mesopic pupil center(pupil center shift) was significantly associated with glare/halo symptoms [odds ratio(OR)=2.065,95% confidence interval(CI)=0.916-4.679,P=0.006] and night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007).The preoperative photopic angle kappa was significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041).The photopic angle kappa was also significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041) and with night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007) in patients implanted with rotationally asymmetric MIOLs.CONCLUSION: A large pupil center shift and misalignment between the visual and pupillary axis(angle kappa)may play a role in the occurrence of photic phenomena after implantation of rotationally asymmetric MIOLs.