Use of computer graphics methods for efficient stray light analysis in optical design

Proceedings of the 32nd International Conference on Computer Graphics and Vision

et al. 2022

In this paper, we consider the problem of calculating the effective protection of an image from spurious radiation, one of the causes of which is the scattering of light on non-imaging elements of an optical device. The purpose of this work is to improve the means of searching and visualizing the sources of parasitic illumination of an image for designing and analyzing the light protection of optical devices. A visualization of the spurious radiation illumination distribution on the surfaces of an optical device is proposed. The global illumination calculation is based on an advanced bi- directional stochastic ray tracing method with backward photon maps. This method is highly efficient, since it simultaneously uses direct and backward photon maps, which accumulate the distributions of the areas of light emission and the visibility of the scattering elements of the optical device, respectively. The method allows representing the average illumination of the image, accumulated on the diffuse objects of the optical device that form the given illumination. By visualizing it, you can more effectively and clearly find the elements of the optical device that create spurious illumination in the image and degrade the image quality. With this information, the designer of an optical device can develop special means of light protection or use special light- absorbing coatings for such elements. The proposed algorithms were implemented in the Lumicept software package, with the help of which the scattered light in the lens objective was calculated and the result of the stray illumination visualization was presented.

Section: Related Workmentioning

confidence: 99%

Methods for Calculating and Visualizing the Spatial Distribution of Illumination in Three-dimensional Models of Optically Complex Scenes

Kinev

Proceedings of the 32nd International Conference on Computer Graphics and Vision

et al. 2022

“…From the point of view of the authors, the most suitable solution for stray light analysis problems is the bidirectional stochastic ray tracing method with progressive backward photon maps 5 . Schematically, this solution is shown in Figure 1.…”

Section: Reviewmentioning

confidence: 99%

“…In this case, it is possible to visualize ray paths, depending on a given criterion that describes any physical phenomenon (reflection, refraction of a ray, etc.) 5 , find sources of stray illumination and evaluate their contribution to the formation of the final image. However, this approach is not very efficient in calculating stray radiation in the case of diffuse light scattering on the elements of an optical device.…”

Section: Introductionmentioning

confidence: 99%

Using multicriteria for ray propagation to analyze scattered light in optical devices

Kinev

Optical Design and Testing XII

et al. 2022

This article explores the possibility of using multicriteria applied to the ray tracing result processing method to improve the efficiency of performing groups of repetitive calculations. If the usual ray tracing criterion is a filter that passes rays in accordance with some condition, usually a series of events that must happen to the ray by the time it reaches the radiation receiver, then multicriteria contains not one criterion, but a set of criteria, each of which is assigned to certain result of the calculation. The proposed concept of multicriteria was developed to solve the problems of scattered light analysis in optical imaging devices. Existing mechanisms make it possible to find sources of stray illumination of an image, but they only show the average value of stray illumination formed by an element of an optical device. In most cases, it is necessary to know the nature of the distribution of stray illumination in the image. Using the concept of multicriteria allows you to effectively solve this problem. Within the framework of one computational process, criteria are formed that correspond to the detected scattered light sources, and each of the criteria is associated with its own image. Using a special technique of ray tracing and processing of ray tracing results, separate results are generated for each of the criteria. This technique can be used not only for the analysis of scattered light, but also for modeling multichannel and multiconfiguration systems. The paper presents the results of scattered light simulation in two optical devices and virtual prototyping of the GP-200 goniophotometer.

“…To solve this problem, one can use the ray path selection criterion for the visualization problem. 12 In accordance with the specified criterion, the ray paths (both forward and backward) traced by the Monte Carlo method through the optical device are analyzed for compliance with the specified criterion, for example, double reflection from lens surfaces (second-order flare) or single scattering on lens frames (caustic illumination), and the rays that meet the specified criteria are selected and rendered. As a result, instead of millions of rays, the designer sees units or dozens of rays, which can indicate the cause of stray lighting in the image.…”

Section: Related Workmentioning

confidence: 99%

“…However, visualization of all ray paths may be unacceptable if the transmission of the optical device for stray radiation is 10−5 or lower. To solve this problem, one can use the ray path selection criterion for the visualization problem 12 . In accordance with the specified criterion, the ray paths (both forward and backward) traced by the Monte Carlo method through the optical device are analyzed for compliance with the specified criterion, for example, double reflection from lens surfaces (second-order flare) or single scattering on lens frames (caustic illumination), and the rays that meet the specified criteria are selected and rendered.…”

Section: Related Workmentioning

confidence: 99%

Methods of visual analysis in the design of the stray light protection of optical devices

et al. 2022

Self Cite

.We provide an analysis of the existing methods for calculating parasitic illumination, methods for its analysis, and visualization. To search for and analyze the sources of stray light in optical devices, a software model of the beam propagation criterion in an optical device is proposed, which makes it possible to select beams that satisfy a given criterion. We consider the possibility of using the method of bidirectional progressive stochastic ray tracing with inverse photon maps to calculate the stray illumination of an image and analyze the causes of its occurrence. To analyze the sources of stray illumination on the radiation detector, it was proposed to use progressive photon maps, which calculated the caustic and secondary components of the illumination and fixed the image illumination on a static regular mesh attached to the surfaces of the optical device. Special visualization tools allow the display of this illumination over the image of an optical device and determination of the elements of the device that have the greatest impact on the level of stray illumination of the image. We present examples of calculation, analysis, and visualization of parasitic illumination of a number of optical systems of lenses with real mechanical structures.