AIM:To evaluate the effect of femtosecond laser small incision lenticule extraction(SMILE)on the binocular visual function in myopic patients with glasses-free threedimensional(3D)technique.METHODS:Totally 50 myopic p...AIM:To evaluate the effect of femtosecond laser small incision lenticule extraction(SMILE)on the binocular visual function in myopic patients with glasses-free threedimensional(3D)technique.METHODS:Totally 50 myopic patients(39 females and 11 males)with SMILE were enrolled in this prospective study.The glasses-free 3D technique was used to evaluate the binocular visual function in these subjects including static stereopsis,dynamic stereopsis,foveal suppression,and binocular balance point of signal to noise ratio(s/n ratio).All subjects received measurements in 1d before operation,and 1d,1wk,and 1mo postoperatively.RESULTS:Both static and dynamic stereopsis showed no significant difference after SMILE.The foveal suppression improved significantly 1wk and 1mo after SMILE(P=0.005 and P=0.007 respectively).The binocular balance point of signal to noise ratio showed a significant improvement 1d,1wk and 1mo after SMILE for both eyes(P<0.001 for each eye respectively).CONCLUSION:Glasses-free 3D technique can be used to evaluate the effect of SMILE on the binocular visual function in myopic patients perceptively,and SMILE can improve both foveal suppression and binocular imbalance in these patients.展开更多
AIM:To assess the effect of experimentally induced anisometropia on binocularity in normal adults with glassesfree three-dimensional(3D)technique.METHODS:Totally 54 healthy medical students with normal binocularity in...AIM:To assess the effect of experimentally induced anisometropia on binocularity in normal adults with glassesfree three-dimensional(3D)technique.METHODS:Totally 54 healthy medical students with normal binocularity in the cross-sectional study were enrolled.Anisometropia was induced by placing trail lenses over the right eye,in 0.5 D steps including lenses of-0.5,-1,-1.5,-2,-2.5 D(hyperopic anisometropia)and lenses of+0.5,+1,+1.5,+2,+2.5 D(myopic anisometropia).The glasses-free 3D technique was used to evaluated not only fine stereopsis,but also coarse stereopsis,dynamic stereopsis,foveal suppression,and peripheral suppression in these subjects.One-way analysis of variance was used to compare quantitative data such as fine stereopsis,coarse stereopsis.Pearson’s Chi-square test was performed to compare categorical data such as dynamic stereopsis,foveal suppression and peripheral suppression.RESULTS:The subjects showed a statistically significant decline in fine stereopsis,coarse stereopsis,and dynamic stereopsis with increasing levels of anisometropia(P<0.001).Binocularity was af fected when induced anisometropia was more than 1 D(P<0.05).Foveal suppression and peripheral suppression were evident and increased in proportion to anisometropia(P<0.001).CONCLUSION:The relatively low degrees of anisometropia may have a potentially significant effect on high-grade binocular interaction.The mechanisms underlying the defect of binocularity seem to involve not only foveal suppression,but also peripheral suppression.展开更多
Background:The accommodation has considerable interactions with the pupil response,vergence response and binocularity.The transformation of visual reception processing and the changes of the binocular cooperation duri...Background:The accommodation has considerable interactions with the pupil response,vergence response and binocularity.The transformation of visual reception processing and the changes of the binocular cooperation during the presbyopia development are still poorly studied.So,the regularities of visual system violation in the presbyopia formation need to be characterized.This study aims to reveal the transformation of visual reception processing and to determine the role of disturbances in binocular interactions in presbyopia formation.Methods:This study included 60 people with emmetropic refraction,uncorrected distance visual acuity 1.0 or higher(decimal scale),normal color perception,without concomitant ophthalmopathology.The first group consisted of 30 people(from 18 to 27 years old)without presbyopia,the second cohort comprised 30 patients(from 45 to 55 years old)with presbyopia.The eyeball anatomy and optics were evaluated using ultrasound biomicroscopy,aberrometry,and pupillometry.The functional state of the visual system was investigated under monocular and binocular conditions.The registration of the disparate fusional reflex limits was performed by the original technic using a diploptic device which facilitated investigation of the binocular interaction under natural conditions without the accommodation response,but with the different vergence load.The disparate fusional reflex was analyzed using the proximal and distal fusion borders,and the convergence and divergence fusion borders.The calculation of the area of binocularity field was performed in cm2.Results:The presbyopia formation is characterized by a change in an intraocular anatomy,optics,visual processing,and binocularity.The processes of binocular interaction inhibition make a significant contribution to the misalignment of the visual perception.The modification of the proximal,distal and convergence fusion borders was determined.It was revealed that 87%of the presbyopic patients had binocularity shortage,whereas the reduction of binocularity field area in extreme grade was seen in 6%of cases.Conclusions:The presbyopia formation is accompanied by a significant reorganization of the visual system activity and by the creation of the new visual processing interactions.These data may be useful in presbyopia surgery.展开更多
AIM:To evaluate the efficacy of the total computer vision syndrome questionnaire(CVS-Q)score as a predictive tool for identifying individuals with symptomatic binocular vision anomalies and refractive errors.METHODS:A...AIM:To evaluate the efficacy of the total computer vision syndrome questionnaire(CVS-Q)score as a predictive tool for identifying individuals with symptomatic binocular vision anomalies and refractive errors.METHODS:A total of 141 healthy computer users underwent comprehensive clinical visual function assessments,including evaluations of refractive errors,accommodation(amplitude of accommodation,positive relative accommodation,negative relative accommodation,accommodative accuracy,and accommodative facility),and vergence(phoria,positive and negative fusional vergence,near point of convergence,and vergence facility).Total CVS-Q scores were recorded to explore potential associations between symptom scores and the aforementioned clinical visual function parameters.RESULTS:The cohort included 54 males(38.3%)with a mean age of 23.9±0.58y and 87 age-matched females(61.7%)with a mean age of 23.9±0.53y.The multiple regression model was statistically significant[R²=0.60,F=13.28,degrees of freedom(DF=17122,P<0.001].This indicates that 60%of the variance in total CVS-Q scores(reflecting reported symptoms)could be explained by four clinical measurements:amplitude of accommodation,positive relative accommodation,exophoria at distance and near,and positive fusional vergence at near.CONCLUSION:The total CVS-Q score is a valid and reliable tool for predicting the presence of various nonstrabismic binocular vision anomalies and refractive errors in symptomatic computer users.展开更多
Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical robots.This st...Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical robots.This study proposes a novel end-to-end disparity estimation model to address these challenges.Our approach combines a Pseudo-Siamese neural network architecture with pyramid dilated convolutions,integrating multi-scale image information to enhance robustness against lighting interferences.This study introduces a Pseudo-Siamese structure-based disparity regression model that simplifies left-right image comparison,improving accuracy and efficiency.The model was evaluated using a dataset of stereo endoscopic videos captured by the Da Vinci surgical robot,comprising simulated silicone heart sequences and real heart video data.Experimental results demonstrate significant improvement in the network’s resistance to lighting interference without substantially increasing parameters.Moreover,the model exhibited faster convergence during training,contributing to overall performance enhancement.This study advances endoscopic image processing accuracy and has potential implications for surgical robot applications in complex environments.展开更多
Passive optical motion capture technology is an effective mean to conduct high-precision pose estimation of small scenes of mobile robots;nevertheless,in the case of complex background and stray light interference in ...Passive optical motion capture technology is an effective mean to conduct high-precision pose estimation of small scenes of mobile robots;nevertheless,in the case of complex background and stray light interference in the scene,due to the infuence of target adhesion and environmental reflection,this technology cannot estimate the pose accurately.A passive binocular optical motion capture technology under complex illumination based on binocular camera and fixed retroreflective marker balls has been proposed.By fixing multiple hemispherical retrorefective marker balls on a rigid base,it uses binocular camera for depth estimation to obtain the fixed position relationship between the feature points.After performing unsupervised state estimation without manual operation,it overcomes the infuence of refection spots in the background.Meanwhile,contour extraction and ellipse least square fitting are used to extract the marker balls with incomplete shape as the feature points,so as to solve the problem of target adhesion in the scene.A FANUC m10i-a robot moving with 6-DOF is used for verification using the above methods in a complex lighting environment of a welding laboratory.The result shows that the average of absolute position errors is 5.793mm,the average of absolute rotation errors is 1.997°the average of relative position errors is 0.972 mm,and the average of relative rotation errors is 0.002°.Therefore,this technology meets the requirements of high-precision measurement in a complex lighting environment when estimating the 6-DOF-motion mobile robot and has very significant application prospects in complex scenes.展开更多
AIM:To evaluate the effects of refractive errors and binocular vision anomalies on the quality of life(QOL)of university students.METHODS:This cross-sectional analytical study was conducted on university students usin...AIM:To evaluate the effects of refractive errors and binocular vision anomalies on the quality of life(QOL)of university students.METHODS:This cross-sectional analytical study was conducted on university students using simple random sampling.Objective refraction,ocular alignment,vergence and accommodative performance were measured and assessed in all participants.Data on QOL were collected using the College of Optometrists in Vision Development-Quality of Life(COVD-QOL)Questionnaire.The effect of mentioned parameters on the QOL were evaluated.RESULTS:Totally 726 students with mean age of 21.35±1.88y were evaluated in this study,51.5%of whom were female.Esophoria was caused significantly lower QOL in the domains of somatic symptoms and occupationalphysical symptoms(P<0.05);Besides,esotropia decreased QOL in domains of somatic symptoms P=0.002 and psychological factors(P=0.023).Students with accommodation insufficiency experienced more symptoms in all domains(P<0.05)except for psychological factors(P=0.07).Increasing in the near point of convergence and accommodation and decreases QOL and increasing accommodative facility increases QOL(all P<0.05).Myopia and astigmatism cause decrease in QOL(both P<0.05),but hyperopic students had better QOL in comparison with others(P<0.05).CONCLUSION:Screening programs and treatment of refractive errors and binocular vision anomalies,especially phoria and accommodative insufficiency,positively impact the QOL and academic achievements of university students.展开更多
Objective:Strabismus is associated with a higher prevalence of idiopathic thoracic scoliosis(ITS)in children.This study aims to investigate whether superior oblique palsy(SOP)poses a higher risk for developing ITS amo...Objective:Strabismus is associated with a higher prevalence of idiopathic thoracic scoliosis(ITS)in children.This study aims to investigate whether superior oblique palsy(SOP)poses a higher risk for developing ITS among children and adolescents.Methods:A cross-sectional study.The study group comprised 347 consecutive candidates for SOP surgery aged 4 to 18 years;Patients within the same age range with ocular trauma were enrolled as the control group.Preoperative chest plain radiographs were used to measure the Cobb angle.Demographic information and clinical data,including diopter,best corrected visual acuity,deviation degree,and binocular function,were analyzed.Results:A significantly higher prevalence of ITS was found in study group compared with control group(12.68%vs 4.18%,P<0.001).Additionally,the mean Cobb angle was lagger in SOP group than that in control group(5.02°±3.87°vs 3.84°±3.09°,P<0.001).Males in SOP group showed a higher prevalence of ITS(12.9%vs 2.87%,P=0.007),but there was no significant difference in females between two groups(12.3%vs 7.69%,P=0.295).Good near stereopsis acuity was significantly associated with high prevalence of thoracic scoliosis(P<0.001).Multivariate logistic regression analysis revealed that a large distant magnitude of deviation(>20 PD)and near stereoacuity were significantly associated with ITS.Conclusions:Patients with SOP have a significantly higher risk of developing idiopathic thoracic scoliosis,especially those with good near stereoscopic and large distant magnitude of deviation.展开更多
To fulfill the need for acquiring three-dimensional(3D) objects with more realistic textures and depth information, this study proposes a method based on near-infrared laser, combined with dual camera field of view ce...To fulfill the need for acquiring three-dimensional(3D) objects with more realistic textures and depth information, this study proposes a method based on near-infrared laser, combined with dual camera field of view center correction and binocular stereo calibration, to precisely capture the target surface texture. Furthermore, we constructed a verification system using standard industrial cameras and line lasers, achieving the generation of binocular line laser point cloud real textures. Experiments conducted within a 400 mm to 600 mm testing range achieved a reconstruction accuracy of 0.047 2 mm and reduced the texture mapping error to 0.323 4 pixel, proving the effectiveness of this method and providing a high-precision, low-cost solution for 3D point cloud model texture mapping.展开更多
Although deep learning methods have been widely applied in slam visual odometry(VO)over the past decade with impressive improvements,the accuracy remains limited in complex dynamic environments.In this paper,a composi...Although deep learning methods have been widely applied in slam visual odometry(VO)over the past decade with impressive improvements,the accuracy remains limited in complex dynamic environments.In this paper,a composite mask-based generative adversarial network(CMGAN)is introduced to predict camera motion and binocular depth maps.Specifically,a perceptual generator is constructed to obtain the corresponding parallax map and optical flow between two neighboring frames.Then,an iterative pose improvement strategy is proposed to improve the accuracy of pose estimation.Finally,a composite mask is embedded in the discriminator to sense structural deformation in the synthesized virtual image,thereby increasing the overall structural constraints of the network model,improving the accuracy of camera pose estimation,and reducing drift issues in the VO.Detailed quantitative and qualitative evaluations on the KITTI dataset show that the proposed framework outperforms existing conventional,supervised learning and unsupervised depth VO methods,providing better results in both pose estimation and depth estimation.展开更多
A stereo matching algorithm based on the epipolar line constraint is designed to meet the real-time and the accuracy requirements. The algorithm is applied to photodynamic therapy binocular surveillance system for por...A stereo matching algorithm based on the epipolar line constraint is designed to meet the real-time and the accuracy requirements. The algorithm is applied to photodynamic therapy binocular surveillance system for port wine stain (PWS) when it monitors the position of the treatment region. The corner matching based on Hu moments is used to calculate the fundamental matrix of the binocular vision system. Experimental results are in agreement with the theoretical calculation.展开更多
Cluster warhead has become the main ammunition of gun,rocket projectile and missile and it has been widely equipped in almost every country.More and more attention is paid to the damage effect of cluster warhead.The s...Cluster warhead has become the main ammunition of gun,rocket projectile and missile and it has been widely equipped in almost every country.More and more attention is paid to the damage effect of cluster warhead.The size of the dispersion area of cluster warhead is the main standard by which the damage effect of cluster warhead is estimated.The practical method of measuring the dispersion area was developed based on binocular stereo vision measurement theory.The calibration principle of the binocular stereo vision cameras was studied.The matching algorithm that relies on the gradient fields of the neighborhood of a pixel has been used to obtain the spatial information of matched points by acquiring apair of corresponding points in the left and right images of binocular cameras.The 3Dpositions of the flying path of cluster warhead were calculated.The umbrella that is similar to the dispersion track of static explosive cluster warhead was applied in the experiment to get the projection area of the umbrella on the ground.Experiment results verify the feasibility of the proposed method.展开更多
Current research of binocular vision systems mainly need to resolve the camera’s intrinsic parameters before the reconstruction of three-dimensional(3D)objects.The classical Zhang’calibration is hardly to calculate ...Current research of binocular vision systems mainly need to resolve the camera’s intrinsic parameters before the reconstruction of three-dimensional(3D)objects.The classical Zhang’calibration is hardly to calculate all errors caused by perspective distortion and lens distortion.Also,the image-matching algorithm of the binocular vision system still needs to be improved to accelerate the reconstruction speed of welding pool surfaces.In this paper,a preset coordinate system was utilized for camera calibration instead of Zhang’calibration.The binocular vision system was modified to capture images of welding pool surfaces by suppressing the strong arc interference during gas metal arc welding.Combining and improving the algorithms of speeded up robust features,binary robust invariant scalable keypoints,and KAZE,the feature information of points(i.e.,RGB values,pixel coordinates)was extracted as the feature vector of the welding pool surface.Based on the characteristics of the welding images,a mismatch-elimination algorithm was developed to increase the accuracy of image-matching algorithms.The world coordinates of matching feature points were calculated to reconstruct the 3D shape of the welding pool surface.The effectiveness and accuracy of the reconstruction of welding pool surfaces were verified by experimental results.This research proposes the development of binocular vision algorithms that can reconstruct the surface of welding pools accurately to realize intelligent welding control systems in the future.展开更多
Objective: To investigate the time and postoperative binocular vision of strabismus surgery for children with intermittent exotropia (X(T)). Methods: A retrospective investigation was conducted in 80 child patie...Objective: To investigate the time and postoperative binocular vision of strabismus surgery for children with intermittent exotropia (X(T)). Methods: A retrospective investigation was conducted in 80 child patients with intermittent exotropia. Pre- and postoperative angles of deviation fixating at near (33 cm) and distant targets (6 m) were measured with the prolonged alternate cover testing. The binocular function was assessed with synoptophore. Twenty-one patients took the postoperative synoptophore exercise. Results: (1) A week after surgery, 96.2% of the 80 patients had binocular normotopia, while a year after surgery, 91.3% of the 80 patients had binocular normotopia; (2) Preoperatively, 58 patients had near stereoacuity, while postoperatively, 72 patients achieved near stereoacuity (P〈0.05); (3) Preoperatively, 64 patients had Grade Ⅰ for the synoptophore evaluation and postoperatively, 76 patients achieved Grade Ⅰ. Meanwhile, 55 patients had Grade Ⅱ preoperatively and 72 achieved Grade Ⅱ postoperatively. For Grade Ⅲ, there were 49 patients preoperatively and 64 patients postoperatively (P〈0.05); (4) Patients of 5-8 years old had a significantly better recovery rate of binocular vision than those of 9-18 years old (P〈0.05); (5) Patients taking postoperative synoptophore exercise had a better binocular vision than those taking no exercise (P〈0.05). Conclusions: (1) Strabismus surgery can help to preserve or restore the binocular vision for intermittent exotropia; (2) Receiving the surgery at young ages may develop better postoperative binocular vision; (3) The postoperative synoptophore exercise can help to restore the binocular vision.展开更多
AIM: To determine the presence of symptomatic accommodative and non-strabismic binocular dysfunctions (A.sBD) in a non-presbyopic population of video display unit (VDU) users with flat-panel displays. METHODS: ...AIM: To determine the presence of symptomatic accommodative and non-strabismic binocular dysfunctions (A.sBD) in a non-presbyopic population of video display unit (VDU) users with flat-panel displays. METHODS: One hundred and one VDU users, aged between 20 to 34y, initially participated in the study. This study excluded contact-lens wearers and subjects who had undergone refractive surgery or had any systemic or ocular disease. First, subjects were asked about the type and nature of eye symptoms they experienced during VDU use. Then, a thorough eye examination excluded those subjects with a significant uncorrected refractive error or other problem, such as ocular motility disorders, vertical deviation, strabismus and eye diseases. Finally, the remaining participants underwent an exhaustive assessment of their accommodative and binocular vision status. RESULTS: Eighty-nine VDU users (46 females and 43 males) were included in this study. They used flat-panel displays for an average of 5±1.9h a day. Twenty subjects presented A.sBD (22.5%). Convergence excess was the most frequent non-strabismic binocular dysfunction (9 subjects), followed by fusional vergence dysfunction (3 subjects) and convergence insufficiency (2 subjects). Within the accommodative dysfunctions, accommodative excess was the most common (4 subjects), followed by accommodative insufficiency (2 subjects). Moderate to severe eye symptoms were found in 13 subjects with ANSBD. CONCLUSION: Significant eye symptoms in VDU users with accommodative and/or non-strabismic binocular dysfunctions often occur and should not be underestimated; therefore, an appropriate evaluation of accommodative and binocular vision status is more important for this population,展开更多
In order to improve the low positioning accuracy and execution efficiency of the robot binocular vision,a binocular vision positioning method based on coarse-fine stereo matching is proposed to achieve object position...In order to improve the low positioning accuracy and execution efficiency of the robot binocular vision,a binocular vision positioning method based on coarse-fine stereo matching is proposed to achieve object positioning.The random fern is used in the coarse matching to identify objects in the left and right images,and the pixel coordinates of the object center points in the two images are calculated to complete the center matching.In the fine matching,the right center point is viewed as an estimated value to set the search range of the right image,in which the region matching is implemented to find the best matched point of the left center point.Then,the similar triangle principle of the binocular vision model is used to calculate the 3D coordinates of the center point,achieving fast and accurate object positioning.Finally,the proposed method is applied to the object scene images and the robotic arm grasping platform.The experimental results show that the average absolute positioning error and average relative positioning error of the proposed method are 8.22 mm and 1.96%respectively when the object's depth distance is within 600 mm,the time consumption is less than 1.029s.The method can meet the needs of the robot grasping system,and has better accuracy and robustness.展开更多
Significant optical engineering advances at the University of Arizona are being made for design, fabrication, and construction of next generation astronomical telescopes. This summary review paper focuses on the techn...Significant optical engineering advances at the University of Arizona are being made for design, fabrication, and construction of next generation astronomical telescopes. This summary review paper focuses on the technological advances in three key areas. First is the optical fabrication technique used for constructing next-generation telescope mirrors. Advances in ground-based telescope control and instrumentation comprise the second area of development. This includes active alignment of the laser truss-based Large Binocular Telescope(LBT) prime focus camera, the new MOBIUS modular cross-dispersion spectroscopy unit used at the prime focal plane of the LBT, and topological pupil segment optimization. Lastly, future space telescope concepts and enabling technologies are discussed. Among these, the Nautilus space observatory requires challenging alignment of segmented multi-order diffractive elements. The OASIS terahertz space telescope presents unique challenges for characterizing the inflatable primary mirror, and the Hyperion space telescope pushes the limits of high spectral resolution, far-UV spectroscopy. The Coronagraphic Debris and Exoplanet Exploring Pioneer(CDEEP) is a Small Satellite(Small Sat) mission concept for high-contrast imaging of circumstellar disks and exoplanets using vector vortex coronagraph. These advances in optical engineering technologies will help mankind to probe, explore, and understand the scientific beauty of our universe.展开更多
An active stereo vision system based on a model of neural pathways of human binocular motor system is proposed. With this model, it is guaranteed that the two cameras of the active stereo vision system can keep their ...An active stereo vision system based on a model of neural pathways of human binocular motor system is proposed. With this model, it is guaranteed that the two cameras of the active stereo vision system can keep their lines of sight fixed on the same target object during smooth pursuit. This feature is very important for active stereo vision systems, since not only 3D reconstruction needs the two cameras have an overlapping field of vision, but also it can facilitate the 3D reconstruction algorithm. To evaluate the effectiveness of the proposed method, some software simulations are done to demonstrate the same target tracking characteristic in a virtual environment apt to mistracking easily. Here, mistracking means two eyes track two different objects separately. Then the proposed method is implemented in our active stereo vision system to perform real tracking task in a laboratory scene where several persons walk self-determining. Before the proposed model is implemented in the system, mistracking occurred frequently. After it is enabled, mistracking never occurred. The result shows that the vision system based on neural pathways of human binocular motor system can reliably avoid mistracking.展开更多
In this study,we explored the neural mechanism underlying impaired stereopsis and possible functional plasticity after strabismus surgery.We enrolled 18 stereo-deficient patients with intermittent exotropia before and...In this study,we explored the neural mechanism underlying impaired stereopsis and possible functional plasticity after strabismus surgery.We enrolled 18 stereo-deficient patients with intermittent exotropia before and after surgery,along with 18 healthy controls.Functional magnetic resonance imaging data were collected when participants viewed three-dimensional stimuli.Compared with controls,preoperative patients showed hypoactivation in higher-level dorsal(visual and parietal)areas and ventral visual areas.Pre-and postoperative activation did not significantly differ in patients overall;patients with improved stereopsis showed stronger postoperative activation than preoperative activation in the right V3A and left intraparietal sulcus.Worse stereopsis and fusional control were correlated with preoperative hypoactivation,suggesting that cortical deficits along the two streams might reflect impaired stereopsis in intermittent exotropia.The correlation between improved stereopsis and activation in the right V3A after surgery indicates that functional plasticity may underlie the improvement of stereopsis.Thus,additional postoperative strategies are needed to promote functional plasticity and enhance the recovery of stereopsis.展开更多
基金Supported by Sichuan Science and Technology Program(No.23NSFSC0856).
文摘AIM:To evaluate the effect of femtosecond laser small incision lenticule extraction(SMILE)on the binocular visual function in myopic patients with glasses-free threedimensional(3D)technique.METHODS:Totally 50 myopic patients(39 females and 11 males)with SMILE were enrolled in this prospective study.The glasses-free 3D technique was used to evaluate the binocular visual function in these subjects including static stereopsis,dynamic stereopsis,foveal suppression,and binocular balance point of signal to noise ratio(s/n ratio).All subjects received measurements in 1d before operation,and 1d,1wk,and 1mo postoperatively.RESULTS:Both static and dynamic stereopsis showed no significant difference after SMILE.The foveal suppression improved significantly 1wk and 1mo after SMILE(P=0.005 and P=0.007 respectively).The binocular balance point of signal to noise ratio showed a significant improvement 1d,1wk and 1mo after SMILE for both eyes(P<0.001 for each eye respectively).CONCLUSION:Glasses-free 3D technique can be used to evaluate the effect of SMILE on the binocular visual function in myopic patients perceptively,and SMILE can improve both foveal suppression and binocular imbalance in these patients.
基金Supported by Sichuan Science and Technology Program (No.23NSFSC0856)。
文摘AIM:To assess the effect of experimentally induced anisometropia on binocularity in normal adults with glassesfree three-dimensional(3D)technique.METHODS:Totally 54 healthy medical students with normal binocularity in the cross-sectional study were enrolled.Anisometropia was induced by placing trail lenses over the right eye,in 0.5 D steps including lenses of-0.5,-1,-1.5,-2,-2.5 D(hyperopic anisometropia)and lenses of+0.5,+1,+1.5,+2,+2.5 D(myopic anisometropia).The glasses-free 3D technique was used to evaluated not only fine stereopsis,but also coarse stereopsis,dynamic stereopsis,foveal suppression,and peripheral suppression in these subjects.One-way analysis of variance was used to compare quantitative data such as fine stereopsis,coarse stereopsis.Pearson’s Chi-square test was performed to compare categorical data such as dynamic stereopsis,foveal suppression and peripheral suppression.RESULTS:The subjects showed a statistically significant decline in fine stereopsis,coarse stereopsis,and dynamic stereopsis with increasing levels of anisometropia(P<0.001).Binocularity was af fected when induced anisometropia was more than 1 D(P<0.05).Foveal suppression and peripheral suppression were evident and increased in proportion to anisometropia(P<0.001).CONCLUSION:The relatively low degrees of anisometropia may have a potentially significant effect on high-grade binocular interaction.The mechanisms underlying the defect of binocularity seem to involve not only foveal suppression,but also peripheral suppression.
文摘Background:The accommodation has considerable interactions with the pupil response,vergence response and binocularity.The transformation of visual reception processing and the changes of the binocular cooperation during the presbyopia development are still poorly studied.So,the regularities of visual system violation in the presbyopia formation need to be characterized.This study aims to reveal the transformation of visual reception processing and to determine the role of disturbances in binocular interactions in presbyopia formation.Methods:This study included 60 people with emmetropic refraction,uncorrected distance visual acuity 1.0 or higher(decimal scale),normal color perception,without concomitant ophthalmopathology.The first group consisted of 30 people(from 18 to 27 years old)without presbyopia,the second cohort comprised 30 patients(from 45 to 55 years old)with presbyopia.The eyeball anatomy and optics were evaluated using ultrasound biomicroscopy,aberrometry,and pupillometry.The functional state of the visual system was investigated under monocular and binocular conditions.The registration of the disparate fusional reflex limits was performed by the original technic using a diploptic device which facilitated investigation of the binocular interaction under natural conditions without the accommodation response,but with the different vergence load.The disparate fusional reflex was analyzed using the proximal and distal fusion borders,and the convergence and divergence fusion borders.The calculation of the area of binocularity field was performed in cm2.Results:The presbyopia formation is characterized by a change in an intraocular anatomy,optics,visual processing,and binocularity.The processes of binocular interaction inhibition make a significant contribution to the misalignment of the visual perception.The modification of the proximal,distal and convergence fusion borders was determined.It was revealed that 87%of the presbyopic patients had binocularity shortage,whereas the reduction of binocularity field area in extreme grade was seen in 6%of cases.Conclusions:The presbyopia formation is accompanied by a significant reorganization of the visual system activity and by the creation of the new visual processing interactions.These data may be useful in presbyopia surgery.
基金Supported by Ongoing Research Funding Program(ORFFT-2025-054-1),King Saud University,Riyadh,Saudi Arabia.
文摘AIM:To evaluate the efficacy of the total computer vision syndrome questionnaire(CVS-Q)score as a predictive tool for identifying individuals with symptomatic binocular vision anomalies and refractive errors.METHODS:A total of 141 healthy computer users underwent comprehensive clinical visual function assessments,including evaluations of refractive errors,accommodation(amplitude of accommodation,positive relative accommodation,negative relative accommodation,accommodative accuracy,and accommodative facility),and vergence(phoria,positive and negative fusional vergence,near point of convergence,and vergence facility).Total CVS-Q scores were recorded to explore potential associations between symptom scores and the aforementioned clinical visual function parameters.RESULTS:The cohort included 54 males(38.3%)with a mean age of 23.9±0.58y and 87 age-matched females(61.7%)with a mean age of 23.9±0.53y.The multiple regression model was statistically significant[R²=0.60,F=13.28,degrees of freedom(DF=17122,P<0.001].This indicates that 60%of the variance in total CVS-Q scores(reflecting reported symptoms)could be explained by four clinical measurements:amplitude of accommodation,positive relative accommodation,exophoria at distance and near,and positive fusional vergence at near.CONCLUSION:The total CVS-Q score is a valid and reliable tool for predicting the presence of various nonstrabismic binocular vision anomalies and refractive errors in symptomatic computer users.
基金Supported by Sichuan Science and Technology Program(2023YFSY0026,2023YFH0004)Supported by the Institute of Information&Communications Technology Planning&Evaluation(IITP)grant funded by the Korean government(MSIT)(No.RS-2022-00155885,Artificial Intelligence Convergence Innovation Human Resources Development(Hanyang University ERICA)).
文摘Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical robots.This study proposes a novel end-to-end disparity estimation model to address these challenges.Our approach combines a Pseudo-Siamese neural network architecture with pyramid dilated convolutions,integrating multi-scale image information to enhance robustness against lighting interferences.This study introduces a Pseudo-Siamese structure-based disparity regression model that simplifies left-right image comparison,improving accuracy and efficiency.The model was evaluated using a dataset of stereo endoscopic videos captured by the Da Vinci surgical robot,comprising simulated silicone heart sequences and real heart video data.Experimental results demonstrate significant improvement in the network’s resistance to lighting interference without substantially increasing parameters.Moreover,the model exhibited faster convergence during training,contributing to overall performance enhancement.This study advances endoscopic image processing accuracy and has potential implications for surgical robot applications in complex environments.
基金the National Key Research and Development Program of China(No.2018YFB1305005)。
文摘Passive optical motion capture technology is an effective mean to conduct high-precision pose estimation of small scenes of mobile robots;nevertheless,in the case of complex background and stray light interference in the scene,due to the infuence of target adhesion and environmental reflection,this technology cannot estimate the pose accurately.A passive binocular optical motion capture technology under complex illumination based on binocular camera and fixed retroreflective marker balls has been proposed.By fixing multiple hemispherical retrorefective marker balls on a rigid base,it uses binocular camera for depth estimation to obtain the fixed position relationship between the feature points.After performing unsupervised state estimation without manual operation,it overcomes the infuence of refection spots in the background.Meanwhile,contour extraction and ellipse least square fitting are used to extract the marker balls with incomplete shape as the feature points,so as to solve the problem of target adhesion in the scene.A FANUC m10i-a robot moving with 6-DOF is used for verification using the above methods in a complex lighting environment of a welding laboratory.The result shows that the average of absolute position errors is 5.793mm,the average of absolute rotation errors is 1.997°the average of relative position errors is 0.972 mm,and the average of relative rotation errors is 0.002°.Therefore,this technology meets the requirements of high-precision measurement in a complex lighting environment when estimating the 6-DOF-motion mobile robot and has very significant application prospects in complex scenes.
文摘AIM:To evaluate the effects of refractive errors and binocular vision anomalies on the quality of life(QOL)of university students.METHODS:This cross-sectional analytical study was conducted on university students using simple random sampling.Objective refraction,ocular alignment,vergence and accommodative performance were measured and assessed in all participants.Data on QOL were collected using the College of Optometrists in Vision Development-Quality of Life(COVD-QOL)Questionnaire.The effect of mentioned parameters on the QOL were evaluated.RESULTS:Totally 726 students with mean age of 21.35±1.88y were evaluated in this study,51.5%of whom were female.Esophoria was caused significantly lower QOL in the domains of somatic symptoms and occupationalphysical symptoms(P<0.05);Besides,esotropia decreased QOL in domains of somatic symptoms P=0.002 and psychological factors(P=0.023).Students with accommodation insufficiency experienced more symptoms in all domains(P<0.05)except for psychological factors(P=0.07).Increasing in the near point of convergence and accommodation and decreases QOL and increasing accommodative facility increases QOL(all P<0.05).Myopia and astigmatism cause decrease in QOL(both P<0.05),but hyperopic students had better QOL in comparison with others(P<0.05).CONCLUSION:Screening programs and treatment of refractive errors and binocular vision anomalies,especially phoria and accommodative insufficiency,positively impact the QOL and academic achievements of university students.
基金the National Natural Science Foundation of China grant NSFC(82070995).
文摘Objective:Strabismus is associated with a higher prevalence of idiopathic thoracic scoliosis(ITS)in children.This study aims to investigate whether superior oblique palsy(SOP)poses a higher risk for developing ITS among children and adolescents.Methods:A cross-sectional study.The study group comprised 347 consecutive candidates for SOP surgery aged 4 to 18 years;Patients within the same age range with ocular trauma were enrolled as the control group.Preoperative chest plain radiographs were used to measure the Cobb angle.Demographic information and clinical data,including diopter,best corrected visual acuity,deviation degree,and binocular function,were analyzed.Results:A significantly higher prevalence of ITS was found in study group compared with control group(12.68%vs 4.18%,P<0.001).Additionally,the mean Cobb angle was lagger in SOP group than that in control group(5.02°±3.87°vs 3.84°±3.09°,P<0.001).Males in SOP group showed a higher prevalence of ITS(12.9%vs 2.87%,P=0.007),but there was no significant difference in females between two groups(12.3%vs 7.69%,P=0.295).Good near stereopsis acuity was significantly associated with high prevalence of thoracic scoliosis(P<0.001).Multivariate logistic regression analysis revealed that a large distant magnitude of deviation(>20 PD)and near stereoacuity were significantly associated with ITS.Conclusions:Patients with SOP have a significantly higher risk of developing idiopathic thoracic scoliosis,especially those with good near stereoscopic and large distant magnitude of deviation.
基金supported by the Program for Innovative Research Team in University of Tianjin (No.TD13-5036)the Tianjin Science and Technology Popularization Project (No.22KPXMRC00090)。
文摘To fulfill the need for acquiring three-dimensional(3D) objects with more realistic textures and depth information, this study proposes a method based on near-infrared laser, combined with dual camera field of view center correction and binocular stereo calibration, to precisely capture the target surface texture. Furthermore, we constructed a verification system using standard industrial cameras and line lasers, achieving the generation of binocular line laser point cloud real textures. Experiments conducted within a 400 mm to 600 mm testing range achieved a reconstruction accuracy of 0.047 2 mm and reduced the texture mapping error to 0.323 4 pixel, proving the effectiveness of this method and providing a high-precision, low-cost solution for 3D point cloud model texture mapping.
基金supported by the Program of Graduate Education and Teaching Reform in Tianjin University of Technology(Nos.YBXM2204 and ZDXM2202)the National Natural Science Foundation of China(Nos.62203331 and 62103299)。
文摘Although deep learning methods have been widely applied in slam visual odometry(VO)over the past decade with impressive improvements,the accuracy remains limited in complex dynamic environments.In this paper,a composite mask-based generative adversarial network(CMGAN)is introduced to predict camera motion and binocular depth maps.Specifically,a perceptual generator is constructed to obtain the corresponding parallax map and optical flow between two neighboring frames.Then,an iterative pose improvement strategy is proposed to improve the accuracy of pose estimation.Finally,a composite mask is embedded in the discriminator to sense structural deformation in the synthesized virtual image,thereby increasing the overall structural constraints of the network model,improving the accuracy of camera pose estimation,and reducing drift issues in the VO.Detailed quantitative and qualitative evaluations on the KITTI dataset show that the proposed framework outperforms existing conventional,supervised learning and unsupervised depth VO methods,providing better results in both pose estimation and depth estimation.
基金Supported by the National High Technology Research and Development Program of China("863"Program)(2007AA04Z231)~~
文摘A stereo matching algorithm based on the epipolar line constraint is designed to meet the real-time and the accuracy requirements. The algorithm is applied to photodynamic therapy binocular surveillance system for port wine stain (PWS) when it monitors the position of the treatment region. The corner matching based on Hu moments is used to calculate the fundamental matrix of the binocular vision system. Experimental results are in agreement with the theoretical calculation.
基金National Major Scientific Equipment Development Projects of China(No.2013YQ240803)Natural Science Foundation for Young Scientists of Shanxi Province(No.2012021011-1)Scientific and Technological Project in Shanxi Province(No.20140321010-02)
文摘Cluster warhead has become the main ammunition of gun,rocket projectile and missile and it has been widely equipped in almost every country.More and more attention is paid to the damage effect of cluster warhead.The size of the dispersion area of cluster warhead is the main standard by which the damage effect of cluster warhead is estimated.The practical method of measuring the dispersion area was developed based on binocular stereo vision measurement theory.The calibration principle of the binocular stereo vision cameras was studied.The matching algorithm that relies on the gradient fields of the neighborhood of a pixel has been used to obtain the spatial information of matched points by acquiring apair of corresponding points in the left and right images of binocular cameras.The 3Dpositions of the flying path of cluster warhead were calculated.The umbrella that is similar to the dispersion track of static explosive cluster warhead was applied in the experiment to get the projection area of the umbrella on the ground.Experiment results verify the feasibility of the proposed method.
基金Supported by National Natural Science Foundation of China(Grant No.51775313)Major Program of Shandong Province Natural Science Foundation(Grant No.ZR2018ZC1760)Young Scholars Program of Shandong University(Grant No.2017WLJH24).
文摘Current research of binocular vision systems mainly need to resolve the camera’s intrinsic parameters before the reconstruction of three-dimensional(3D)objects.The classical Zhang’calibration is hardly to calculate all errors caused by perspective distortion and lens distortion.Also,the image-matching algorithm of the binocular vision system still needs to be improved to accelerate the reconstruction speed of welding pool surfaces.In this paper,a preset coordinate system was utilized for camera calibration instead of Zhang’calibration.The binocular vision system was modified to capture images of welding pool surfaces by suppressing the strong arc interference during gas metal arc welding.Combining and improving the algorithms of speeded up robust features,binary robust invariant scalable keypoints,and KAZE,the feature information of points(i.e.,RGB values,pixel coordinates)was extracted as the feature vector of the welding pool surface.Based on the characteristics of the welding images,a mismatch-elimination algorithm was developed to increase the accuracy of image-matching algorithms.The world coordinates of matching feature points were calculated to reconstruct the 3D shape of the welding pool surface.The effectiveness and accuracy of the reconstruction of welding pool surfaces were verified by experimental results.This research proposes the development of binocular vision algorithms that can reconstruct the surface of welding pools accurately to realize intelligent welding control systems in the future.
基金Project supported by the National Natural Science Foundation of China(No.30600693)Department of Education of Zhejiang Province(No.20030236),China
文摘Objective: To investigate the time and postoperative binocular vision of strabismus surgery for children with intermittent exotropia (X(T)). Methods: A retrospective investigation was conducted in 80 child patients with intermittent exotropia. Pre- and postoperative angles of deviation fixating at near (33 cm) and distant targets (6 m) were measured with the prolonged alternate cover testing. The binocular function was assessed with synoptophore. Twenty-one patients took the postoperative synoptophore exercise. Results: (1) A week after surgery, 96.2% of the 80 patients had binocular normotopia, while a year after surgery, 91.3% of the 80 patients had binocular normotopia; (2) Preoperatively, 58 patients had near stereoacuity, while postoperatively, 72 patients achieved near stereoacuity (P〈0.05); (3) Preoperatively, 64 patients had Grade Ⅰ for the synoptophore evaluation and postoperatively, 76 patients achieved Grade Ⅰ. Meanwhile, 55 patients had Grade Ⅱ preoperatively and 72 achieved Grade Ⅱ postoperatively. For Grade Ⅲ, there were 49 patients preoperatively and 64 patients postoperatively (P〈0.05); (4) Patients of 5-8 years old had a significantly better recovery rate of binocular vision than those of 9-18 years old (P〈0.05); (5) Patients taking postoperative synoptophore exercise had a better binocular vision than those taking no exercise (P〈0.05). Conclusions: (1) Strabismus surgery can help to preserve or restore the binocular vision for intermittent exotropia; (2) Receiving the surgery at young ages may develop better postoperative binocular vision; (3) The postoperative synoptophore exercise can help to restore the binocular vision.
文摘AIM: To determine the presence of symptomatic accommodative and non-strabismic binocular dysfunctions (A.sBD) in a non-presbyopic population of video display unit (VDU) users with flat-panel displays. METHODS: One hundred and one VDU users, aged between 20 to 34y, initially participated in the study. This study excluded contact-lens wearers and subjects who had undergone refractive surgery or had any systemic or ocular disease. First, subjects were asked about the type and nature of eye symptoms they experienced during VDU use. Then, a thorough eye examination excluded those subjects with a significant uncorrected refractive error or other problem, such as ocular motility disorders, vertical deviation, strabismus and eye diseases. Finally, the remaining participants underwent an exhaustive assessment of their accommodative and binocular vision status. RESULTS: Eighty-nine VDU users (46 females and 43 males) were included in this study. They used flat-panel displays for an average of 5±1.9h a day. Twenty subjects presented A.sBD (22.5%). Convergence excess was the most frequent non-strabismic binocular dysfunction (9 subjects), followed by fusional vergence dysfunction (3 subjects) and convergence insufficiency (2 subjects). Within the accommodative dysfunctions, accommodative excess was the most common (4 subjects), followed by accommodative insufficiency (2 subjects). Moderate to severe eye symptoms were found in 13 subjects with ANSBD. CONCLUSION: Significant eye symptoms in VDU users with accommodative and/or non-strabismic binocular dysfunctions often occur and should not be underestimated; therefore, an appropriate evaluation of accommodative and binocular vision status is more important for this population,
基金supported by National Natural Science Foundation of China(No.61125101)。
文摘In order to improve the low positioning accuracy and execution efficiency of the robot binocular vision,a binocular vision positioning method based on coarse-fine stereo matching is proposed to achieve object positioning.The random fern is used in the coarse matching to identify objects in the left and right images,and the pixel coordinates of the object center points in the two images are calculated to complete the center matching.In the fine matching,the right center point is viewed as an estimated value to set the search range of the right image,in which the region matching is implemented to find the best matched point of the left center point.Then,the similar triangle principle of the binocular vision model is used to calculate the 3D coordinates of the center point,achieving fast and accurate object positioning.Finally,the proposed method is applied to the object scene images and the robotic arm grasping platform.The experimental results show that the average absolute positioning error and average relative positioning error of the proposed method are 8.22 mm and 1.96%respectively when the object's depth distance is within 600 mm,the time consumption is less than 1.029s.The method can meet the needs of the robot grasping system,and has better accuracy and robustness.
基金the Gordon and Betty Moore Foundation for their financial support of the development of the MODElens and its enabling alignment technologiesthe II-VI Foundation Block-Gift,Technology Research Initiative Fund Optics/Imaging Program。
文摘Significant optical engineering advances at the University of Arizona are being made for design, fabrication, and construction of next generation astronomical telescopes. This summary review paper focuses on the technological advances in three key areas. First is the optical fabrication technique used for constructing next-generation telescope mirrors. Advances in ground-based telescope control and instrumentation comprise the second area of development. This includes active alignment of the laser truss-based Large Binocular Telescope(LBT) prime focus camera, the new MOBIUS modular cross-dispersion spectroscopy unit used at the prime focal plane of the LBT, and topological pupil segment optimization. Lastly, future space telescope concepts and enabling technologies are discussed. Among these, the Nautilus space observatory requires challenging alignment of segmented multi-order diffractive elements. The OASIS terahertz space telescope presents unique challenges for characterizing the inflatable primary mirror, and the Hyperion space telescope pushes the limits of high spectral resolution, far-UV spectroscopy. The Coronagraphic Debris and Exoplanet Exploring Pioneer(CDEEP) is a Small Satellite(Small Sat) mission concept for high-contrast imaging of circumstellar disks and exoplanets using vector vortex coronagraph. These advances in optical engineering technologies will help mankind to probe, explore, and understand the scientific beauty of our universe.
文摘An active stereo vision system based on a model of neural pathways of human binocular motor system is proposed. With this model, it is guaranteed that the two cameras of the active stereo vision system can keep their lines of sight fixed on the same target object during smooth pursuit. This feature is very important for active stereo vision systems, since not only 3D reconstruction needs the two cameras have an overlapping field of vision, but also it can facilitate the 3D reconstruction algorithm. To evaluate the effectiveness of the proposed method, some software simulations are done to demonstrate the same target tracking characteristic in a virtual environment apt to mistracking easily. Here, mistracking means two eyes track two different objects separately. Then the proposed method is implemented in our active stereo vision system to perform real tracking task in a laboratory scene where several persons walk self-determining. Before the proposed model is implemented in the system, mistracking occurred frequently. After it is enabled, mistracking never occurred. The result shows that the vision system based on neural pathways of human binocular motor system can reliably avoid mistracking.
基金supported by the National Natural Science Foundation of China(82271117,8201001029 and 81730025)Shanghai 2022 Science and Technology Innovation Action Plan(22ZR1410200).
文摘In this study,we explored the neural mechanism underlying impaired stereopsis and possible functional plasticity after strabismus surgery.We enrolled 18 stereo-deficient patients with intermittent exotropia before and after surgery,along with 18 healthy controls.Functional magnetic resonance imaging data were collected when participants viewed three-dimensional stimuli.Compared with controls,preoperative patients showed hypoactivation in higher-level dorsal(visual and parietal)areas and ventral visual areas.Pre-and postoperative activation did not significantly differ in patients overall;patients with improved stereopsis showed stronger postoperative activation than preoperative activation in the right V3A and left intraparietal sulcus.Worse stereopsis and fusional control were correlated with preoperative hypoactivation,suggesting that cortical deficits along the two streams might reflect impaired stereopsis in intermittent exotropia.The correlation between improved stereopsis and activation in the right V3A after surgery indicates that functional plasticity may underlie the improvement of stereopsis.Thus,additional postoperative strategies are needed to promote functional plasticity and enhance the recovery of stereopsis.