Dear Sir,Eye drops(single use)commonly used in clinics do have varying pH values.The use of such drops in the initial management of chemical eye injury may influence the accuracy of pH measurement of the eye,and subse...Dear Sir,Eye drops(single use)commonly used in clinics do have varying pH values.The use of such drops in the initial management of chemical eye injury may influence the accuracy of pH measurement of the eye,and subsequently influence its management.Chemical eye injury is an ophthalmic emergency,which may be caused by exposure to an acidic(pH【4)or an alkali(pH】10)solution to the eye.Rinsing the eye decreases the concentration of these solutions on ocular surface.The initial management would be copious irrigation with clean or sterile water or Ringer’s solution(pH 7.3-7.4)or its equivalent,of a展开更多
Depth from defocus is one technology for depth estimation.We estimate particle depth information from two defocused images captured simultaneously by two coaxial cameras with different imaging distances.The images are...Depth from defocus is one technology for depth estimation.We estimate particle depth information from two defocused images captured simultaneously by two coaxial cameras with different imaging distances.The images are processed with the Fourier transform to obtain the characteristic parameter(i.e.,the standard deviation of the relative blur kernel of these two defocused images).First,we theoretically analyze the functional relationship between the object depth and the standard deviation or variation of the relative blur kernel.Then,we verify the relationship experimentally.We analyze the influence of particle size,window size and image noise on the calibration curves using both numerical simulations and experiments.We obtain the depth range and accuracy of this measurement system experimentally.For the verification experiments,we use a sample of glass microbeads and the irregularly-shaped dust particles on a microscope slide.Both of these experiments present a suitable depth measurement result.Finally,we apply the measuring system to the depth estimation of drops from a small anti-fogging spray.The results show that our system and image processing algorithm are robust for different types of particles,facilitating the in-line three-dimensional positioning of particles.展开更多
文摘Dear Sir,Eye drops(single use)commonly used in clinics do have varying pH values.The use of such drops in the initial management of chemical eye injury may influence the accuracy of pH measurement of the eye,and subsequently influence its management.Chemical eye injury is an ophthalmic emergency,which may be caused by exposure to an acidic(pH【4)or an alkali(pH】10)solution to the eye.Rinsing the eye decreases the concentration of these solutions on ocular surface.The initial management would be copious irrigation with clean or sterile water or Ringer’s solution(pH 7.3-7.4)or its equivalent,of a
基金The authors gratefully acknowledge support from the National Natural Science Foundation of China(51576130,51327803)the Basic Research Program of Major Projects for Aeronautical and Gas Turbines(2017-V-0016-0069)the Educational Development Foundation of Shanghai Municipal Education Commission(14CG46).
文摘Depth from defocus is one technology for depth estimation.We estimate particle depth information from two defocused images captured simultaneously by two coaxial cameras with different imaging distances.The images are processed with the Fourier transform to obtain the characteristic parameter(i.e.,the standard deviation of the relative blur kernel of these two defocused images).First,we theoretically analyze the functional relationship between the object depth and the standard deviation or variation of the relative blur kernel.Then,we verify the relationship experimentally.We analyze the influence of particle size,window size and image noise on the calibration curves using both numerical simulations and experiments.We obtain the depth range and accuracy of this measurement system experimentally.For the verification experiments,we use a sample of glass microbeads and the irregularly-shaped dust particles on a microscope slide.Both of these experiments present a suitable depth measurement result.Finally,we apply the measuring system to the depth estimation of drops from a small anti-fogging spray.The results show that our system and image processing algorithm are robust for different types of particles,facilitating the in-line three-dimensional positioning of particles.
