|
Schmidt–Pechan Prism
A Schmidt–Pechan prism is a type of optical prism used to rotate an image by 180°. These prisms are commonly used in binoculars as an ''image erecting system''. The Schmidt–Pechan prism makes use of a roof prism section (from the German: "Dachkante", lit. ''roof edge''). Binoculars designs using Schmidt–Pechan prisms can be constructed more compactly than ones using Porro or Uppendahl roof and Abbe–Koenig roof prisms. A Schmidt–Pechan prism is sometimes called a Pechan prism pair. Method of operation The Schmidt-Pechan is based on the Pechan prism design: Both are a composite of two prisms, separated by an air gap. Because of the air gap there are four glass/air transition surfaces. The Pechan design will invert or revert (flip) the image, depending on the orientation of the prism, but not both at the same time. For the Schmidt-Pechan design, the upper prism from the Pechan design is replaced with a Schmidt roof prism, so the Schmidt–Pechan prism can both i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schmidt Prism
Schmidt may refer to: * Schmidt (surname), including list of people with the surname * Schmidt (singer) (born 1990), German pop and jazz singer * Schmidt (lunar crater), a small lunar impact crater * Schmidt (Martian crater), a crater on Mars * Schmidt (volcano), in Kamchatka * Schmidt Block, listed on the National Register of Historic Places in Scott County, Iowa, USA * Schmidt Brewery, a St. Paul brewery * Schmidt camera, an astronomical telescope designed for photography * Schmidt–Cassegrain telescope, a version of the Schmidt camera * Schmidt Site, an archeological site in Michigan, USA, listed on the National Register of Historic Places in 1973 * Schmidt Spiele, a German games manufacturer * Schmidt Baking Company, makers of Schmidt's Blue Ribbon Bread * von Schmidt auf Altenstadt, a German baronial family in Kirchgattendorf, part of the municipality of Gattendorf * Schmidt Island, an island in the Novaya Zemlya archipelago in the Arctic Ocean * Schmidt Peninsula (Sakhal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reflectivity
The reflectance of the surface of a material is its effectiveness in reflecting radiant energy. It is the fraction of incident electromagnetic power that is reflected at the boundary. Reflectance is a component of the response of the electronic structure of the material to the electromagnetic field of light, and is in general a function of the frequency, or wavelength, of the light, its polarization, and the angle of incidence. The dependence of reflectance on the wavelength is called a ''reflectance spectrum'' or ''spectral reflectance curve''. Mathematical definitions Hemispherical reflectance The ''hemispherical reflectance'' of a surface, denoted , is defined as R = \frac, where is the radiant flux ''reflected'' by that surface and is the radiant flux ''received'' by that surface. Spectral hemispherical reflectance The ''spectral hemispherical reflectance in frequency'' and ''spectral hemispherical reflectance in wavelength'' of a surface, denoted and respectively, are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Critical Angle (optics)
Total internal reflection (TIR) is the optical phenomenon in which waves arriving at the interface (boundary) from one medium to another (e.g., from water to air) are not refracted into the second ("external") medium, but completely reflected back into the first ("internal") medium. It occurs when the second medium has a higher wave speed (i.e., lower refractive index) than the first, and the waves are incident at a sufficiently oblique angle on the interface. For example, the water-to-air surface in a typical fish tank, when viewed obliquely from below, reflects the underwater scene like a mirror with no loss of brightness (Fig.1). TIR occurs not only with electromagnetic waves such as light and microwaves, but also with other types of waves, including sound and water waves. If the waves are capable of forming a narrow beam (Fig.2), the reflection tends to be described in terms of "rays" rather than waves; in a medium whose properties are independent of direction, such as air, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swarovski Optik
Swarovski Optik is a division of the Swarovski group of companies, manufacturing optical instruments. Its headquarters are located in Absam, Tyrol, Austria. History Wilhelm Swarovski, son of the original founder, was born in 1918. In 1935, with the help of his father, he developed a prism fabrication and grinding process that he used in the design of his first 6×30 binocular. In 1949 he has founded SWAROVSKI OPTIK KG in Absam, Tyro, to produce the Habicht 7×42 that it continues produce today. * 1935 First Swarovski binoculars, which was a 6×30 * 1949 Formation of Swarovski Optik * 1959 First Swarovski Optik rifle scope (4×32) * 1967 First Swarovski Optik extendable spotting scope (30×75) * 1974 Kahles was purchased by Swarovski Optik * 1977 Kahles became a branch of Swarovski Optik * 1989 Kahles Limited again became an independent company within the Swarovski group * 1991 First AT 80 telescope * 1993 First hunting rifle scope with reticle illumination * 1995 First rifl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Coating
An optical coating is one or more thin layers of material deposited on an optical component such as a lens, prism or mirror, which alters the way in which the optic reflects and transmits light. These coatings have become a key technology in the field of optics. One type of optical coating is an anti-reflective coating, which reduces unwanted reflections from surfaces, and is commonly used on spectacle and camera lenses. Another type is the high-reflector coating, which can be used to produce mirrors that reflect greater than 99.99% of the light that falls on them. More complex optical coatings exhibit high reflection over some range of wavelengths, and anti-reflection over another range, allowing the production of dichroic thin-film filters. Types of coating The simplest optical coatings are thin layers of metals, such as aluminium, which are deposited on glass substrates to make mirror surfaces, a process known as silvering. The metal used determines the reflection charac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prism (optics)
An optical prism is a transparent optics, optical element with flat, polished surfaces that are designed to refraction, 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 prism (geometry), 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 glass, acrylic and fluorite#Optics, fluorite. A dispersive prism can be used to break white#White light, white light up into its constituent spectral colors (the colors of the rainbow) as described in the following section. Other types of prisms noted below can be used to reflection (physics), reflect light, or to split light into components with different polarization (w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Total Internal Reflection
Total internal reflection (TIR) is the optical phenomenon in which waves arriving at the interface (boundary) from one medium to another (e.g., from water to air) are not refracted into the second ("external") medium, but completely reflected back into the first ("internal") medium. It occurs when the second medium has a higher wave speed (i.e., lower refractive index) than the first, and the waves are incident at a sufficiently oblique angle on the interface. For example, the water-to-air surface in a typical fish tank, when viewed obliquely from below, reflects the underwater scene like a mirror with no loss of brightness (Fig.1). TIR occurs not only with electromagnetic waves such as light and microwaves, but also with other types of waves, including sound and water waves. If the waves are capable of forming a narrow beam (Fig.2), the reflection tends to be described in terms of "rays" rather than waves; in a medium whose properties are independent of direction, such as air, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Handedness
In human biology, handedness is an individual's preferential use of one hand, known as the dominant hand, due to it being stronger, faster or more Fine motor skill, dextrous. The other hand, comparatively often the weaker, less dextrous or simply less subjectively preferred, is called the non-dominant hand. In a study from 1975 on 7688 children in US grades 1-6, Left handers comprised 9.6% of the sample, with 10.5% of male children and 8.7% of female children being left-handed. Handedness is often defined by one's writing hand, as it is fairly common for people to prefer to do some tasks with each hand. There are examples of true ambidexterity (equal preference of either hand), but it is rare—most people prefer using one hand for most purposes. Most of the current research suggests that left-handedness has an epigenetic marker—a combination of genetics, biology and the environment. Because the vast majority of the population is right-handed, many devices are designed for u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bauernfeind Prism
A Bauernfeind prism is a type of reflecting prism used to deviate a beam of light by 45° to 60°, depending on its construction, while neither flipping nor rotating the image. It is named for its inventor, the German expert of geodesy Karl Maximilian von Bauernfeind. The beam is reflected twice in the prism, with one reflection happening at less than the critical angle. Therefore, the prism requires a reflective coating for this surface to be usable in practice. A Bauernfeind prism with 45° beam deviation is also known as a half-penta prism or semipentaprism. A Bauernfeind prism is used together with a Schmidt roof prism to form a Schmidt–Pechan prism. Applications The Bauernfeind prism is commonly used in microscope tubes and in geodesy to deviate the path to the eyepiece in order make the device more ergonomic. More recent applications are glasses that deflect the viewing angle either downwards (for relaxed reading or watching TV), or upwards (as in belay glasses Belay ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pechan Prism
Pechan is a surname. Notable people with the surname include: * Albert Pechan (1902–1969), American politician * Karel Pechan (1901–?), Czech cyclist {{Short pages monitor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
