Angular aperture

About: Angular aperture is a research topic. Over the lifetime, 1771 publications have been published within this topic receiving 27257 citations.

Imaging lens capable of shifting image, imaging optical device, and digital equipment

Abstract: PROBLEM TO BE SOLVED: To provide an imaging lens enabling substantial miniaturization and vibration control, and an imaging optical device and digital equipment mounted with the imaging lens.SOLUTION: A single-focus lens comprises, in order from an object side, a first lens group Gr1 having positive power as a whole lens group and an aperture diaphragm ST adjacent to or inside the lens group, and a second lens group Gr2 having positive or negative power as a whole lens group and an aspherical lens where any one of lens surfaces has negative power at the center portion and positive power at the periphery portion. Image blur is corrected, with the second lens group Gr2 fixed in position, by a shifting or tilting operation of the first lens group Gr1, or by the combination of the shifting and tilting operation of the first lens group Gr1. In addition, the following formulas are satisfied: 0.3

Light beats the diffraction limit

Abstract: Physicists have long been fascinated by the propagation of light through small apertures – from simple pinhole cameras to the more complex diffraction patterns of peacock feathers. Diffraction results from the interference of electromagnetic waves emerging from an aperture larger than the wavelength of the incident light. As the size of the aperture approaches the wavelength of the light, the aperture begins to resemble a point source of spherical waves. And when the aperture is smaller than the wavelength – beyond the diffraction limit – transmission is greatly reduced.

Passive collimating skylight

Abstract: A passive collimating skylight system includes an energy-receiving aperture defining a first plane and an energy-delivering aperture defining a second plane that is spaced apart from and non-parallel to the first plane. An energy-directing passageway extends between the energy-receiving aperture and the energy-delivering aperture to redirect radiant energy incident on the energy-collecting aperture over a range of incidence angles to the energy-delivering aperture so that the redirected radiant energy emerges from the energy-delivering aperture over a range of emergence angles that is smaller than the range of incidence angles. The passageway is defined by a wall having a first end that defines the energy-delivering aperture and a second end that defines the energy-collecting aperture, the wall tapering inwardly and having a reflective inner surface along substantially the entire length from the first end to the second end. At least a portion of the wall of the passageway can be made of a flexible reflective film.

Focal point oriented aperture

Abstract: A focus orientating aperture for a high energy radiation beam from a source (16) comprises, an absorption cylinder (10) capable of periodic motion, e.g. axial rotation, and provided with one or more apertures (14), such that all radiation incident on the cylinder surface is absorbed, but a uni-directional ray (18) along the axis of the aperture is transmitted to an investigated sample or work surface. an INDEPENDENT CLAIM is included for a method of manufacturing a perforated absorption cylinder, particularly by the use of a high pressure (approx.3800 bar) water cutting jet. Dependent on the application, the absorption cylinder may comprise e.g. a cylindrical outer sheath of copper, tungsten, or heavy metal, with an inner core of polyethylene or boron. The collimation device can be used in the reverse sense to handle radiation scattered from a surface, with a detection element positioned at the focal point (16).

Fundamental diffraction limitations in a paraxial 4-f imaging system with coherent and incoherent illumination

Abstract: In the usual model of an imaging system, only the effects of the aperture stop are considered in determining diffraction-limited system performance. In fact, diffraction at other stops—those associated with different lens elements, for example—can also affect system performance and cause the imaging to be space variant, even in the absence of vignetting in the conventional ray optics sense. For the 4-f imaging system investigated in this paper, the severity of the space variance depends on the relative sizes of the two lens stops and the aperture stops. If the diameters of the lenses are equal, the aperture of the first lens has a greater effect on system performance than does that of the second.