Did you know TracePro features an incredibly powerful Importance Sampling capability? Importance Sampling is an extremely helpful and useful tool for stray light analysis, as well as many other optical design and analysis challenges. An example would be off-axis light entering a telescope and scattering off an interior surface and towards the detector. This stray light can cause reduced performance and a degradation in the image produced. With standard ray tracing methods low probability paths, such as scattered light, may be under sampled and it may be difficult to get accurate results efficiently. Importance Sampling allows the user to improve the sampling by defining targets that the rays are biased or sampled towards. A key feature of Importance Sampling is that the correct flux is maintained, so even though more rays reach the target, the results are still accurate and can be trusted. Importance Sampling is also much more efficient than simply increasing the number of rays traced, so the task can be done more efficiently and more accurately. Importance Sampling can save you time and money. Importance Sampling is available in the Standard and Expert editions of TracePro.
Figure 1: 100k rays started, no Importance Sampling
Figure 2: 100k rays started, no Importance Sampling, 110 rays get to detector
Figure 3: 100k rays started, with Importance Sampling
Figure 4: 100k rays started, with Importance Sampling, >67k rays get to detector