|
Spotting Scope
A spotting scope is a compact lightweight portable telescope optimized for detailed observation of distant objects. They are used as tripod mounted optical enhancement devices for various outdoor activities such as birdwatching, skygazing and other naturalist activities, for hunting and target shooting to verify a marksman's shot placements, for tactical ranging and surveillance, and for any other application that requires higher magnification than ordinary binoculars (typically 20× to 60×). The light-gathering power and resolution of a spotting scope is determined by the diameter of the objective lens, typically between . The larger the objective, the more massive and expensive the telescope. The optical assembly has a small refracting objective lens, an internal image-erecting system, and an eyepiece that is usually removable. The image-erecting system may use relay lenses, prisms such as Porro or roof prisms, or a catadioptric system of the Schmidt or Maksutov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yukon Spotting Scope
Yukon () is a territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s westernmost territory and the smallest territory by land area. As of the 2021 census, Yukon is the middle territory in terms of population, but the most densely populated. Yukon has an estimated population of 47,126 as of 2025. Whitehorse, the territorial capital, is the largest settlement. Yukon was split from the Northwest Territories by a federal statute in 1898 as the Yukon Territory. The current governing legislation is a new statute passed by the federal Parliament in 2002, the ''Yukon Act''. That act established Yukon as the territory's official name, although Yukon Territory remains in popular usage. Canada Post uses the territory's internationally approved postal abbreviation of YT. In 2021, territorial government policy was changed so that The Yukon would be recom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refracting Telescope
A refracting telescope (also called a refractor) is a type of optical telescope that uses a lens (optics), lens as its objective (optics), objective to form an image (also referred to a dioptrics, dioptric telescope). The refracting telescope design was originally used in spyglasses and astronomy, astronomical telescopes but is also used for long-focus lens, long-focus camera lenses. Although large refracting telescopes were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures. A refractor's magnification is calculated by dividing the focal length of the objective lens by that of the eyepiece. Refracting telescopes typically have a lens at the front, then a optical train, long tube, then an eyepiece or instrumentation at the rear, where the telescope view comes to focus. Originally, telescopes had an objective of one element, but a century later, tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stadiametric Rangefinding
Stadiametric rangefinding, or the stadia method / stadiametry, is a technique of measuring distances with a telescopic instrument. The term stadia comes from a Greek unit of length '' Stadion'' (equal to 600 Greek feet, ''pous'') which was the typical length of a sports stadium of the time. Stadiametric rangefinding is used for surveying and in the telescopic sights of firearms, artillery pieces, or tank guns, as well as some binoculars and other optics. It is still widely used in long-range military sniping, but in many professional applications it is being replaced with microwave, infrared, or laser rangefinding methods. Although much easier to use, electronic rangefinders can give away the shooter's position to a well-equipped adversary, and the need for accurate range estimation has existed for much longer than electronic rangefinders small and rugged enough to be suitable for military use. Principle The stadia method is based upon the principle of similar triangles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reticle
A reticle or reticule, also known as a graticule or crosshair, is a pattern of fine lines or markings built into the eyepiece of an optical device such as a telescopic sight, spotting scope, theodolite, optical microscope or the electronic visual display, screen of an oscilloscope, to provide frame of reference, measurement references during visual inspections. Today, engraved lines or embedded fibers may be replaced by a digital image superimposed on a screen or eyepiece. Both terms may be used to describe any set of patterns used for aiding visual measurements and calibrations, but in modern use ''reticle'' is most commonly used for weapon sight (device), sights, while ''graticule'' is more widely used for non-weapon measuring instruments such as oscilloscope#Graticule, oscilloscope display, astronomic telescopes, microscopes and microscope slide, slides, surveying instruments and other similar devices. There are many variations of reticle pattern; this article concerns its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Control Knob
{{more citations needed, date=January 2017 A control knob is a rotary device used to provide manual input adjustments to a mechanical/ electrical system when grasped and turned by a human operator, so that differing extent of knob rotation corresponds to different desired input. Control knobs are a simpler type of input hardware and one of the most common components in control systems, and are found on all sorts of devices from taps and gas stoves to optical microscopes, potentiometers, radio tuners and digital cameras, as well as in aircraft cockpits.https://www.amazon.com/b?node=16412811 Operation A control knob works by turning a shaft which connects to the component which produces the actual input. Common control components used include potentiometers, variable capacitors, and rotary switches. An example where the knob does not produce a variation in an electrical signal may be found in many toasters, where the darkness knob moves the thermostat A thermostat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ergonomics
Ergonomics, also known as human factors or human factors engineering (HFE), is the application of Psychology, psychological and Physiology, physiological principles to the engineering and design of products, processes, and systems. Primary goals of human factors engineering are to reduce human error, increase productivity and system availability, and enhance safety, health and comfort with a specific focus on the interaction between the human and equipment. The field is a combination of numerous disciplines, such as psychology, sociology, engineering, biomechanics, industrial design, physiology, anthropometry, interaction design, visual design, user experience, and user interface design. Human factors research employs methods and approaches from these and other knowledge disciplines to study human behavior and generate data relevant to previously stated goals. In studying and sharing learning on the design of equipment, devices, and processes that fit the human body and its Cog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maksutov Telescope
250px, A 150mm aperture Maksutov–Cassegrain telescope The Maksutov (also called a "Mak") is a catadioptric telescope design that combines a spherical mirror with a weakly negative meniscus lens in a design that takes advantage of all the surfaces being nearly "spherically symmetrical". The negative lens is usually full diameter and placed at the entrance pupil of the telescope (commonly called a "corrector plate" or "meniscus corrector shell"). The design corrects the problems of off-axis aberrations such as coma found in reflecting telescopes while also correcting chromatic aberration. It was patented in 1941 by Soviet optician Dmitri Dmitrievich Maksutov. Maksutov based his design on the idea behind the Schmidt camera of using the spherical errors of a negative lens to correct the opposite errors in a spherical primary mirror. The design is most commonly seen in a Cassegrain variation, with an integrated secondary, that can use all-spherical elements, thereby simplifying ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catadioptric System
A catadioptric optical system is one where refraction and Reflection (physics), reflection are combined in an optical system, usually via lens (optics), lenses (dioptrics) and curved mirrors (catoptrics). Catadioptric combinations are used in focusing systems such as searchlights, headlamps, early lighthouse focusing systems, optical telescopes, microscopes, and telephoto photographic lens, lenses. Other optical systems that use lenses and mirrors are also referred to as "catadioptric", such as surveillance catadioptric sensors. Early catadioptric systems Catadioptric combinations have been used for many early optical systems. In the 1820s, Augustin-Jean Fresnel developed several catadioptric lighthouse reflector versions of his Fresnel lens. Léon Foucault developed a catadioptric microscope in 1859 to counteract aberrations of using a lens to image objects at high power. In 1876 a French engineer, A. Mangin, invented what has come to be called the Mangin mirror, a concave glas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roof Prism
A roof prism, also called a Dachkanten prism or Dach prism (from German: ''Dachkante'', lit. "roof edge"), is a reflective prism containing a section where two faces meet at a 90° angle, resembling the roof of a building and thus the name. Reflection from the two 90° faces returns an image that is flipped laterally across the axis where the faces meet. Characteristic for a roof prism is that the beam is split in half, with one half of the beam hitting first one face then the other face, while it is invert for the other half of the beam. Therefore, a roof prism can be used only with some distance to focal planes, or the "edge" of the roof would introduce slight distortions. Furthermore, the angle between the two faces has to be very close to 90°, or image quality would be degraded. The simplest roof prism is the Amici roof prism, with other common roof prism designs being the Abbe–Koenig prism, the Schmidt–Pechan prism and probably the best known being the roof pentap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porro Prism
In optics, a Porro prism, named for its inventor Ignazio Porro, is a type of ''reflection prism'' used in optical instruments to alter the orientation of an image. Description It consists of a block of material shaped like a right geometric prism with right-angled triangular end faces. In operation, light enters the large rectangular face of the prism, undergoes total internal reflection twice from the sloped faces, and exits again through the large rectangular face. When the light enters and therefore exits the glass at normal incidence, the prism is not dispersive. An image travelling through a Porro prism is rotated by 180° and exits in the opposite direction offset from its entry point. While a single Porro prism can be constructed to work as well as a roof prism, it is seldom used as such. Therefore, to reduce the cost of production for a Porro prism, the edge of the roof is usually left out. Sometimes only one small window as an entrance surface and one window as e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prism (optics)
An optical prism is a transparent optical element with flat, polished surfaces that are designed to refract light. At least one surface must be angled—elements with two parallel surfaces are ''not'' prisms. The most familiar type of optical prism is the triangular prism, which has a triangular base and rectangular sides. Not all optical prisms are geometric prisms, and not all geometric prisms would count as an optical prism. Prisms can be made from any material that is transparent to the wavelengths for which they are designed. Typical materials include glass, acrylic and fluorite. A dispersive prism can be used to break white light up into its constituent spectral colors (the colors of the rainbow) to form a spectrum as described in the following section. Other types of prisms noted below can be used to reflect light, or to split light into components with different polarizations. Types Dispersive ''Dispersive prisms'' are used to break up light into its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
