A Methodology to Model the Rain and Fog Effect on the Performance of Automotive LiDAR Sensors

In this work, we introduce a novel approach to model the rain and fog effect on the light detection and ranging (LiDAR) sensor performance for the simulation-based testing of LiDAR systems. The proposed methodology allows for the simulation of the rain and fog effect using the rigorous applications of the Mie scattering theory on the time domain for transient and point cloud levels for spatial analyses. The time domain analysis permits us to benchmark the virtual LiDAR signal attenuation and signal-to-noise ratio (SNR) caused by rain and fog droplets. In addition, the detection rate (DR), false detection rate (FDR), and distance error derror of the virtual LiDAR sensor due to rain and fog droplets are evaluated on the point cloud level. The mean absolute percentage error (MAPE) is used to quantify the simulation and real measurement results on the time domain and point cloud levels for the rain and fog droplets. The results of the simulation and real measurements match well on the time domain and point cloud levels if the simulated and real rain distributions are the same. The real and virtual LiDAR sensor performance degrades more under the influence of fog droplets than in rain.

Knotless scleral fixation for implanting a posterior chamber intraocular lens

I describe a technique for implanting an intraocular lens by scleral fixation sutures that has the advantages of knotless fixation of the haptics and an out-in approach for passing the needle through the sclera.

Nd:YAG laser posterior hyaloidotomy in subhyaloid hemorrhage

Subhyaloid hemorrhage is usually a benign condition that generally improves spontaneously and rarely causes visual loss. However, because subhyaloid hemorrhage may be associated with permanent macular changes before it spontaneously resolves, posterior Nd:YAG hyaloidotomy may be indicated in selected patients. We performed Q-switched Nd:YAG laser posterior hyaloidotomy via the transcorneal route in two cases of subhyaloid hemorrhage. The hemorrhage instantaneously drained into the vitreous cavity, resulting in a dramatic increase in visual acuity.

Improving estimation of corneal refractive power by measuring the posterior curvature of the cornea

We developed a formula to measure the posterior curvature of the cornea. In our study, real corneal power in 51 eyes was calculated by using anterior and posterior curvatures and corneal thickness. The corneal refractive index was found to be a variable value between 1.3243 and 1.3339 (mean 1.3304 +/- 0.0003).