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The reflector is a metallic surface formed into a paraboloid of revolution and usually truncated in a circular rim that forms the diameter of the antenna.
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reflector and is
The measurements made with the NRL 50-foot reflector, which is altitude-azimuth-mounted, would have shown a systematic change with local hour angle in the measured intensities of Venus and Jupiter if a substantial part of the radiation had been linearly polarized.
Therefore, it works as a neutron reflector and neutron moderator, effectively slowing the neutrons to the thermal energy range of below 0. 03 eV, where the total cross section is at least an order of magnitude lower – exact value strongly depends on the purity and size of the crystallites in the material.
However, an episode of Richard Hammond's Engineering Connections relating to the Keck Observatory ( whose reflector glass is based on the Archimedes ' Mirror ) did successfully use a much smaller curved mirror to burn a wooden model, though not made of the same quality of materials as in the MythBusters effort.
Finally, a protective coating of a photo-polymerizable lacquer is applied on top of the metal reflector and cured with UV-light.
The McMath-Pierce Solar Telescope on the facilities is the largest solar telescope in the world and the largest unobstructed reflector ( it doesn't have a secondary mirror in the path of incoming light ).
Kitt Peak is famous for hosting the first telescope ( an old 91 cm reflector ) used to search for near-Earth asteroids, and calculating the probability of an impact with planet Earth.
It is an electronically modulated optical device made up of any number of segments filled with liquid crystals and arrayed in front of a light source ( backlight ) or reflector to produce images in color or monochrome.
This twisted phase reorients light that has passed through the first polarizer, allowing its transmission through the second polarizer ( and reflected back to the observer if a reflector is provided ).
The best-known instance is the parabolic reflector, which is a mirror or similar reflective device that concentrates light or other forms of electromagnetic radiation to a common focal point, or conversely, collimates light from a point source at the focus into a parallel beam.
Frequency shift is caused by motion that changes the number of wavelengths between the reflector and the radar.
When the reflector is moving at right angle to the radar beam, it has no relative velocity.
The modulation index riding on the receive signal is proportional to the time delay between the radar and the reflector.
Applied similarly to the parabolic reflector, the slotted waveguide is moved mechanically to scan and is particularly suitable for non-tracking surface scan systems, where the vertical pattern may remain constant.
* Using bounce flash in which the flash head is aimed at a nearby pale colored surface such as a ceiling or wall or at a specialist photographic reflector.
( Aluminium slightly outdoes silver in parts of the visible spectrum, and silver is a poor reflector of ultraviolet ).
Silver is seldom used as the reflector in telescope mirrors where aluminum is generally preferred being cheaper and less susceptible to tarnishing and corrosion Silver is the reflective coating of choice for solar reflectors.
Wrapping the weapon's fissile core in a neutron reflector ( which is standard on all nuclear explosives ) can dramatically reduce the critical mass.
In this case the maximum temperature is whatever the container wall ( typically a neutron reflector of some sort ) can withstand, while actively cooled by the hydrogen.
In telecommunications and radar, a Cassegrain antenna is a parabolic antenna in which the feed radiator is mounted at or behind the surface of the concave main parabolic reflector dish and is aimed at a smaller convex secondary reflector suspended in front of the primary reflector.
reflector and metallic
NASA Glenn Research Center, for example, used a mirror comprising a reflective aluminum surface on a metallic honeycomb as a prototype reflector unit for a proposed power system for the International Space Station.
reflector and surface
If there is more than one reflective surface in the antenna, as in a corner reflector antenna, each surface forms its own image of the antenna elements.
If the sun-facing surface is an almost perfect reflector, the force would approach double that ( 7. 22 µPa ) depending on how close to an ideal reflector the surface is polished.
A very large solar reflector would be constructed nearby, focusing solar heat onto the asteroid, first to weld and seal the tunnel ends, then more diffusely to slowly heat the entire outer surface.
The parabolic reflector functions due to the geometric properties of the paraboloidal shape: if the angle of incidence to the inner surface of the collector equals the angle of reflection, then any incoming ray that is parallel to the axis of the dish will be reflected to a central point, or " focus ".
A parabolic antenna is an antenna that uses a parabolic reflector, a curved surface with the cross-sectional shape of a parabola, to direct the radio waves.
* Shape errors-random surface errors in the shape of the reflector reduce efficiency.
Flashlight using a " total internal reflection " assembly have a transparent optical element ( light pipe ) to guide light from the source into a beam ; no reflector surface is required.
Titan's surface is thought to be a poor reflector of ELF waves, so the waves may instead be reflecting off the liquid-ice boundary of a subsurface ocean of water and ammonia, the existence of which is predicted by some theoretical models.
The laser resonator consists of two distributed Bragg reflector ( DBR ) mirrors parallel to the wafer surface with an active region consisting of one or more quantum wells for the laser light generation in between.
The dome acts as a reflector, retaining all stray light and reflecting it onto the surface of the sensor, minimizing losses in a relatively long optical channel.
For a simple vertically traveling wave, the travel time from the surface to the reflector and back is called the Two-Way Time ( TWT ) and is given by the formula
Prior to its use in surface search radar, such systems used a parabolic segment reflector.
The balloon satellite functioned as a reflector, not a transmitter, so that after it was placed in a low Earth orbit, a signal would be sent to it, reflected or bounced off its surface, and then returned to Earth.
The reflector is sometimes made of aluminum foil, sometimes merely a white-pigmented surface or, as in the 3M Vikuiti ESR, consists of hundreds of polymer layers of alternating low and high refractive index.
: If a surface is not a perfect reflector, distortion arises in the reflected light.
reflector and formed
Because of the poor reflectivity of the speculum mirrors of that day, Herschel eliminated the small diagonal mirror of a standard newtonian reflector from his design and tilted his primary mirror so he could view the formed image directly.
Other factors affecting the front to back ratio of a parabolic microwave antenna include the material of the dish and the precision with which the reflector itself was formed.
A parabolic reflector pointing upward can be formed by rotating a reflective liquid, like mercury, around a vertical axis.
In optics, an anti-resonant reflecting optical waveguide ( ARROW ) is formed from an anti-resonant Fabry – Pérot reflector.
reflector and into
Microscopic corner reflector structures can be incorporated into reflective paint for increased visibility at night, although retroreflective spherical beads are more common for this purpose.
* An amplitude splitting interferometer uses a partial reflector to divide the amplitude of the incident wave into separate beams which are separated and recombined.
During his time as a teacher at Holmewood he set up at his home a 12 ½ inch reflector telescope, which he kept with him into his old age.
The parabolic reflector transforms an incoming plane wave traveling along the axis into a spherical wave converging toward the focus.
The Enigma's reflector guaranteed that no letter could be enciphered as itself, so an A could never turn back into an A.
The operating principle of a parabolic antenna is that a point source of radio waves at the focal point in front of a paraboloidal reflector of conductive material will be reflected into a collimated plane wave beam along the axis of the reflector.
In more complex designs, such as the Cassegrain and Gregorian, a secondary reflector is used to direct the energy into the parabolic reflector from a feed antenna located away from the primary focal point.
In some types the incandescent light bulb has an integral lens that focuses the light, so no reflector is built into the penlight.
A reflector with an approximately parabolic shape concentrates the light emitted by the bulb into a directed beam.
Low key light accentuates the contours of an object by throwing areas into shade while a fill light or reflector may illuminate the shadow areas to control contrast.
The Enigma's reflector ( when used ) guaranteed that no letter could be enciphered as itself, so an A could never turn back into an A.
The main reflector at the DDO remained a major instrument into the 1960s, but in the end even the " remote " location Chant had selected was being encroached on by urban sprawl.
The fitting of HID conversion kits ( which include HID lamps that fit into original headlamp units in place of the original bulbs with no change to the headlamp's lens, reflector or housing ) generally results in extremely high levels of glare, and is illegal throughout most of the world.
Porter used these to build " polar reflector " that he incorporated into the roof of a den he added on to his house in a design that allowed him to observe the sky from indoor heated comfort during long Maine winters.
For comparison, in the parabolic type of antenna a feedhorn at the end of a waveguide directs a conical beam of output energy toward the reflector, whence it is focused into a narrow collimated beam.
# Raised plastic or ceramic units, fastened to asphalt or concrete pavement and often with a reflector built into the edge.
* Radar reflector: A special fixture fitted to a vessel or incorporated into the design of certain aids to navigation to enhance their ability to reflect radar energy.
This allows for more efficient reflector designs that get more light into the aquarium.
The lower end where the cable enters the ground is often encased in a length of yellow plastic reflector to make it more visible, so that people or vehicles do not run into it.
In populated areas, guy wires are often encased in a yellow plastic or wood tube reflector attached to their lower end, so that they can be seen more easily, reducing the chance of people and animals walking into them or vehicles crashing into them.
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