Related papers: Analytical computation of stray light in nested mi…
Optical modules for X-ray telescopes comprise several double-reflection mirrors operating in grazing incidence. The concentration power of an optical module, which determines primarily the telescope's sensitivity, is in general expressed by…
When performing X-ray observations with a Wolter-I telescope, the presence of bright off-axis sources can introduce unfocused rays, known as straylight, which contaminate the detector and compromise the scientific analysis. Among the…
Recent advances in CMOS technology have potential to significantly increase the performance, at low-cost, of an astronomical space telescope. Arrays of sensors in space missions are typically contiguous and act as a monolithic detector. A…
Imaging X-rays by direct focusing offers greater sensitivity and a higher dynamic range compared to techniques based on indirect imaging. The Focusing Optics X-ray Solar Imager (FOXSI) is a sounding rocket payload that uses seven sets of…
Focusing mirrors for X-ray telescopes in grazing incidence, introduced in the 70s, are characterized in terms of their performance by their imaging quality and effective area, which in turn determines their sensitivity. Even though the…
X-ray mirrors with high focusing performances are in use in both mirror modules for X-ray telescopes and in synchrotron and FEL (Free Electron Laser) beamlines. A degradation of the focus sharpness arises in general from geometrical…
The precise determination of the instrumental response function versus wavelength is a central ingredient in contemporary photometric calibration strategies. This typically entails propagating narrowband illumination through the system…
We present total and specular reflectance measurements of various materials that are commonly (and uncommonly) used to provide baffling and/or to minimize the effect of stray light in optical systems. More specifically, we investigate the…
The Solar Corona Imager is an internally occulted coronagraph on board the ASO-S mission, which has the advantage of imaging the inner corona in H I {Lyman-\textalpha} (Ly-alpha) and white-light (WL) wavebands. However, scattering of solar…
We present StrayCats: a catalog of NuSTAR stray light observations of X-ray sources. Stray light observations arise for sources 1--4$^{\circ}$ away from the telescope pointing direction. At this off-axis angle, X-rays pass through a gap…
One of the most important parameters determining the sensitivity of X-ray telescopes is their effective area as a function of the X-ray energy. The computation of the effective area of a Wolter-I mirror, with either a single layer or…
Stray light represents a significant noise source for gravitational wave detectors, requiring an accurate modeling and mitigation to preserve the experiment's sensitivity. In this article, we present an updated and improved analysis of the…
Astronomical imaging with micro-arcsecond ($\mu$as) angular resolution could enable breakthrough scientific discoveries. Previously-proposed $\mu$as X-ray imager designs have been interferometers with limited effective collecting area. Here…
A large space-based telescope aimed at detecting and characterizing the atmospheres of Earth-like planets orbiting Sun-like stars will require unprecedented contrast and stability. However, damage to the primary mirror due to micrometeoroid…
Measurement of stray light in a complex optical system can be a complex task. We developed a method to measure coherent stray light inside an assembled device, determining all stray light sources and their relative contribution. The method…
Stray light significantly influences the detection capabilities of astronomical telescopes. The actual stray-light level during observations depends not only on the telescope's inherent stray-light suppression capability but also on its…
We consider the inverse refractor and the inverse reflector problem. The task is to design a free-form lens or a free-form mirror that, when illuminated by a point light source, produces a given illumination pattern on a target. Both…
Sensing and manipulating targets hidden under scattering media are universal problems that take place in applications ranging from deep-tissue optical imaging to laser surgery. A major issue in these applications is the shallow light…
"Weak" magnetic-field diagnostics in faint objects near the bright solar disk are discussed in terms of the level of non-object signatures, in particular, of the stray light in telescopes. Calculated dependencies of the stray light caused…
An effort towards understanding of the stray light problems for the Xinglong 2.16-m telescope was presented to estimate the stray light performance of the telescope itself and provide a method for improving the stray light suppression. The…