First look at OK Live - an analogue of Periscope. First look at OK Live - analogue of Periscope Similar to periscope
". The plot of the second episode of the second season is based on the fact that the girl wakes up in an unfamiliar house and remembers absolutely nothing. She goes out into the street, and every person she meets takes pictures of her on a smartphone camera. Naturally, she almost goes crazy, not understanding what kind of society it is, in which all people look at the world through the phone screen. Check it out, the show is worth it.
Meerkat and Periscope are two applications that could lead us to such a world. With their help, you can broadcast your life using your smartphone, and viewers around the world will be watching you. It sounds incredibly cool and damn scary at the same time.
Meerkat came out a few months before Periscope, but the latter is nice because the company that owns it is Twitter. We compared two apps and decided which one is cooler.
Meerkat
Since Meerkat came first, we'll start with it. To use the application, registration is required, and this can only be done using a Twitter account. When you enter the application, you will immediately be prompted to create a broadcast, naming it so that the viewers understand what you are going to show. You can start right away or schedule for a specific time.
During the broadcast, you can turn on the front or rear camera, flash, and also open a chat in which the audience and you will communicate.
The broadcast can be ended at any time and is also on Twitter. Your subscribers will receive notifications the moment you start. Meerkat has a leaderboard that shows a list of people with the largest number views and viewers. I didn’t find much use in it, from here you can only go to the user’s Twitter account.
Broadcast in Meerkat can be watched from iOS devices and from a browser, and created only from iOS. There is unofficial application for Android, however, it can only view current broadcasts.
Periscope
Periscope has a stronger social component. When creating an account, by the way, also only through Twitter, you will be prompted to subscribe to popular users, as well as those you follow on Twitter.
And now to the coolest part. If you use Meerkat and do not have a large number subscribers on Twitter, you can not even hope for viewers - they will not be. In Periscope, they begin to pour in, and in large quantities and from all over the world.
Having started the broadcast, I watched 25 viewers after a few minutes, and from the comments at the beginning of the broadcast, a slight hysteria began.
Periscope, like Meerkat, is available only in the iOS version, but you can also watch broadcasts from a browser. An Android app is coming soon.
I don't see the point in using Meerkat, given that many more people will follow your broadcasts on Periscope. Most likely, the power of Twitter will soon make Periscope the only such service.
Try it and tell how you like it. Both Meerkat and Periscope are completely free.
True fans of online broadcasts know that there are applications similar to Periscope. Some of them were launched before the brainchild of Twitter. The most popular among these programs have gained those that will be discussed below.
7 facts about Meerkat
Twitch vs Periscope
Despite the general implementation in the field streaming video Twitch and Periscope are quite different from each other. The main difference is observed in the following categories:
What is Projector TV?
You can install this analogue of Periscope for access to streams and broadcasting only within the operating iOS systems, and versions from the eighth and higher are supported. Unfortunately, the Russian analogue of "Periscope" on "Android" is not yet available and the implementation of such a version by the developer has not yet been advertised.
In addition, for smartphones that are locked in any country, the installation of the program is prohibited.
Obvious plus of analog Periscope on Russian market- the possibility of posting the broadcast on the wall of VKontakte, and the views on this social network are taken into account when compiling the overall popularity rating.
In general, we can say that programs similar to Periscope cannot be called full-fledged analogues today. They are either implemented only for the owners of apple products, or sharpened for completely different purposes. However, the video broadcasting market is just beginning to develop, and, perhaps, worthy competitors among the Russian counterparts of Periscope will soon appear.
". The plot of the second episode of the second season is based on the fact that the girl wakes up in an unfamiliar house and remembers absolutely nothing. She goes out into the street, and every person she meets takes pictures of her on a smartphone camera. Naturally, she almost goes crazy, not understanding what kind of society it is, in which all people look at the world through the phone screen. Check it out, the show is worth it.
Meerkat and Periscope are two applications that could lead us to such a world. With their help, you can broadcast your life using your smartphone, and viewers around the world will be watching you. It sounds incredibly cool and damn scary at the same time.
Meerkat came out a few months before Periscope, but the latter is nice because the company that owns it is Twitter. We compared two apps and decided which one is cooler.
Meerkat
Since Meerkat came first, we'll start with it. To use the application, registration is required, and this can only be done using a Twitter account. When you enter the application, you will immediately be prompted to create a broadcast, naming it so that the viewers understand what you are going to show. You can start right away or schedule for a specific time.
During the broadcast, you can turn on the front or rear camera, flash, and also open a chat in which the audience and you will communicate.
The broadcast can be ended at any time and is also on Twitter. Your subscribers will receive notifications the moment you start. Meerkat has a leaderboard that shows a list of people with the most views and viewers. I didn’t find much use in it, from here you can only go to the user’s Twitter account.
Broadcast in Meerkat can be watched from iOS devices and from a browser, and created only from iOS. There is an unofficial app for Android, but it only allows you to view current broadcasts.
Periscope
Periscope has a stronger social component. When creating an account, by the way, also only through Twitter, you will be prompted to subscribe to popular users, as well as those you follow on Twitter.
And now to the coolest part. If you use Meerkat and don't have a lot of Twitter followers, you can't even hope for viewers - they won't be there. In Periscope, they begin to pour in, and in large quantities and from all over the world.
Having started the broadcast, I watched 25 viewers after a few minutes, and from the comments at the beginning of the broadcast, a slight hysteria began.
Periscope, like Meerkat, is available only in the iOS version, but you can also watch broadcasts from a browser. An Android app is coming soon.
I don't see the point in using Meerkat, given that many more people will follow your broadcasts on Periscope. Most likely, the power of Twitter will soon make Periscope the only such service.
Try it and tell how you like it. Both Meerkat and Periscope are completely free.
L-3 KEO is supplying the U.S. Navy with the Universal Modular Mast (UMM), which serves as a hoist for five different sensors, including the AN/BVS1 Optocoupler Mast, High Speed Data Mast, Multi-Function Masts, and Embedded avionics systems.
Missouri Virginia-class multi-purpose nuclear submarine with two L-3 KEO AN/BVS-1 optocoupler masts. This class of nuclear submarines was the first where only optocoupler masts (commander and observation) of a non-penetrating type were installed
Advanced optronics (optoelectronics) gives mast systems a non-penetrating type obvious advantage compared to direct view periscopes. The vector of development of this technology is currently determined by low-profile optronics and new concepts based on fixed systems.
Interest in optoelectronic periscopes of a non-penetrating type arose in the 80s of the last century. The developers claimed that these systems would increase the submarine's design flexibility and safety. The operational advantages of these systems were the display of the periscope image on multiple screens of the crew, unlike older systems, when only one person could use the periscope, simplification of work and increased capabilities, including the Quick Look Round (QLR) function, which minimized the time spent by the periscope on the surface and thereby reduce the vulnerability of the submarine and, as a result, the likelihood of detection by anti-submarine warfare platforms. The value of the QLR mode has recently been increasing due to the increasing use of submarines for collecting information.
In addition to increasing the flexibility of the submarine design due to the spacing of the control post and optocoupler masts in space, this improves its ergonomics by freeing up the volume previously occupied by periscopes. Non-penetrating type masts can also be relatively easily reconfigured by installing new systems and new features, they have fewer moving parts, which reduces cost. life cycle periscope and, accordingly, the volume of its maintenance, maintenance and overhaul. Continuing technological progress is helping to reduce the likelihood of periscope detection, and further improvements in this area are associated with the transition to low-profile optocoupler masts.
A conventional Type 212A class anti-submarine submarine of the German Navy displays its masts. These diesel-electric submarines of the Type 212A and Todaro classes, supplied respectively to the German and Italian navies, are distinguished by a combination of masts and penetrating (SERO-400) and non-penetrating types (OMS-110)
Virginia class
In early 2015, the US Navy installed a new stealth periscope based on L-3 Communications' low-profile LPPM (Low-Profle Photonics Mast) Block 4 optocoupler mast on its Virginia-class nuclear submarines. In order to reduce the likelihood of detection, this company is also working on a thinned version of the current AN / BVS-1 Kollmorgen optocoupler mast (currently L-3 KEO), installed on submarines of the same class.
L-3 Communications announced in May 2015 that its L-3 KEO optoelectronic systems division (L-3 Communications acquired KEO in February 2012, which led to the creation of L-3 KEO) received following the results of the competition a $48.7 million contract from the US Naval Systems Command (NAVSEA) to develop and design a low-profile mast with an option to manufacture 29 optocoupler masts over four years, plus maintenance. The LPPM mast program maintains the characteristics of the current periscope while reducing its size to the size of more traditional periscopes, such as the Kollmorgen Type-18 periscope, which began to be installed in 1976 on Los Angeles-class nuclear submarines as they entered the fleet.
Although the AN/BVS-1 mast has unique characteristics, it is too large and its shape is unique to the US Navy, which makes it possible to immediately identify the nationality of this submarine when a periscope is detected. According to public information, the LPPM mast has the same diameter as the Type-18 periscope, and its appearance resembles the standard shape of this periscope. The non-penetrating hull-type LPPM modular mast is installed in a universal telescopic modular compartment, which increases the stealth and survivability of submarines.
The features of the system include imaging in the short-wave infrared region of the spectrum, imaging high definition in the visible region of the spectrum, laser ranging and a set of antennas that provide a wide coverage of the electromagnetic spectrum. The prototype of the LPPM L-3 KEO optocoupler mast is the only one in operation today; it is installed aboard the Virginia-class Texas submarine, where all subsystems and operational readiness are checked new system. The first serial mast will be manufactured in 2017 and its installation will begin in 2018. According to L-3 KEO, it plans to develop its LPPM so that NAVSEA can install a single mast on new submarines, as well as modernize existing vessels as part of an ongoing improvement program aimed at improving reliability, capability and affordability. The export variant of the AN/BVS-1 mast, known as the Model 86, was first sold to a foreign customer under a contract announced in 2000 when the Egyptian Navy conceived a major upgrade of its four Romeo-class diesel-electric anti-submarine submarines. Another unnamed customer from Europe has also installed the Model 86 on its diesel-electric submarines (DES).
Periscope systems before installation on a submarine
L-3 KEO, along with the development of LPPM, is already supplying the US Navy with the Universal Modular Mast (UMM). This non-penetrating type mast is installed on Virginia-class submarines. The UMM serves as a hoist for five different sensor systems, including the AN/BVS-1, OE-538 radio mast, high speed data antenna, special mission mast, and integrated avionics antenna mast. KEO received a contract from the US Department of Defense to develop the UMM mast in 1995. In April 2014, L-3 KEO was awarded a $15 million contract to supply 16 UMM masts to be installed on several Virginia-class nuclear submarines.
Another customer of UMM is the Italian fleet, which also equipped its diesel-electric submarines of the Todaro class of the first and second batches with this mast; the last two boats were scheduled to be delivered in 2015 and 2016 respectively. L-3 KEO also owns the Italian periscope company Calzoni, which developed the E-UMM (Electronic UMM) electrically powered mast, which eliminated the need for an external hydraulic system for raising and lowering the periscope.
L-3 KEO's latest offering is the AOS (Attack Optronic System) non-penetrating command optronic system. This low profile mast combines the characteristics of the traditional Model 76IR search periscope and the same company's Model 86 optocoupler mast (see above). The mast has reduced visual and radar signatures, weighs 453 kg, and has a sensor head diameter of only 190 mm. The AOS Mast Sensor Kit includes a laser rangefinder, a thermal imager, a high-definition camera, and a low-light camera.
Images from the optical-electronic mast L-3 KEO AN / BVS-1 are displayed on the operator's workplace. Non-penetrating type masts improve the ergonomics of the central station, as well as increase safety due to the structural integrity of the hull
In the first half of the 90s, the German company Carl Zeiss (currently Airbus Defense and Space) began preliminary development of its Optronic Mast System (OMS). The first customer of the serial version of the mast, which received the designation OMS-110, was the South African fleet, which chose this system for three of its Heroine-class diesel-electric submarines, which were delivered in 2005-2008. The Greek Navy also chose the OMS-110 mast for its Papanikolis diesel-electric submarines, and after it decided to buy this mast South Korea for their diesel-electric submarines of the Chang Bogo class. Masts of the non-penetrating OMS-110 type have also been installed on the Indian Navy's Shishumar-class submarines and the traditional anti-submarine Tridente-class submarines of the Portuguese Navy. One of latest applications OMS-110 was the installation of universal UMM masts (see above) on the submarines of the Italian fleet "Todaro" and anti-submarine submarines of the German fleet class "Type 2122". These boats will have a combination of an OMS-110 optocoupler mast and a SERO 400 command periscope (hull-penetrating type) from Airbus Defense and Space. The OMS-110 Optocoupler Mast features 2-axis line-of-sight stabilization, a third-generation medium-wavelength thermal imaging camera, a high-definition TV camera, and an optional eye-safe laser rangefinder. The Quick Panoramic View mode allows you to get a quick, programmable 360-degree panoramic view. It can reportedly be completed by the OMS-110 system in less than three seconds.
Airbus Defense and Security has developed the OMS-200 Low Profile Optocoupler Mast, either as an addition to the OMS-110 or as a standalone solution. Showcased at Defense Security and Equipment International 2013 in London, this mast features advanced stealth technology and a compact design. Modular, compact, low-profile, non-penetrating command/search optocoupler mast OMS-200 combines various sensors in a single housing with radar-absorbing coating. As a "replacement" for the traditional direct-view periscope, the OMS-200 is specifically designed to remain stealth in the visible, infrared and radar spectra. Optocoupler mast OMS-200 combines three sensors, a high-definition television camera, a short-wave thermal imager and an eye-safe laser rangefinder. Image from high quality and high resolution from a shortwave thermal imager can be complemented by an image from a medium wave thermal imager, especially in conditions of poor visibility, such as fog or haze. According to the company, the OMS-200 system can combine images into one picture with excellent stabilization.
Sagem has developed and started production of the Series 30 family of commander and search masts, which are ordered by many navies, including the French. The commander's mast has a low visual profile.
Scorpene-class diesel-electric submarines built by DCNS are equipped with a combination of penetrating and non-penetrating masts from Sagem, including a Series 30 mast with four optocoupler sensors: a high-resolution television camera, a thermal imager, a low-light television camera and a laser rangefinder
SERIES 30
At Euronaval 2014 in Paris, Sagem announced that it has been selected by South Korean shipyard Daewoo Shipbuilding and Marine Engineering (DSME) to supply non-penetrating optocoupler masts for the equipment of South Korean new Son-Won-II class diesel-electric submarines, for which DSME is the lead contractor. This contract marked the export success of Sagem's latest Search Optronic Mast (SOM) Series 30 family. This non-penetrating type optocoupler search mast can simultaneously receive more than four advanced opto-electronic channels and a full array of electronic warfare and Global Positioning System (GPS) antennas; everything is housed in a lightweight touch container. The Series 30 SOM optocoupler mast sensors include a high-resolution thermal imager, a high-resolution TV camera, a low-light TV camera, and an eye-safe laser rangefinder. The mast can receive a GPS antenna, an early warning avionics antenna, a DF antenna, and a communications antenna. Among the operating modes of the system there is a fast circular view mode, while all channels are available at the same time. Dual-screen digital displays have an intuitive graphical user interface.
Sagem has already delivered a Series 30 SOM variant for the new Barracuda-class diesel-electric submarines of the French fleet, while another variant has been sold to an as-yet unnamed foreign customer. According to Sagem, the Series 30 SOM mast supplied to the South Korean Navy will also include an electronic intelligence antenna, as well as optical communications equipment operating in the infrared range. A command variant of the Series 30 SOM is also available, designated the Series 30 AOM; it features a low profile mast and is fully compatible with the Series 30 SOM variant in terms of mechanical, electronic and software interfaces. The same container and cables can be used for both sensor units, allowing fleets to select the optimal configuration for specific applications. The basic kit includes a high-resolution thermal imager, a high-definition television camera, an optional eye-safe laser rangefinder, a shortwave thermal imager and a day/night backup camera.
Thales has equipped all Astute-class submarines in the British Navy with optocoupler masts with CM010 and CM011 sensor heads. These products form the basis for a promising new series of periscopes.
Pilkington Optronics' lineage dates back to 1917, when its predecessor became the sole supplier to the British Navy. At one time, this company (now part of Tales) began on its own initiative to develop the CM010 family of optocoupler masts, installing a prototype in 1996 on the Trafalgar nuclear submarine of the British Navy, after which in 2000 it was selected by BAE Systems to equip new Astute-class nuclear submarines. A CM010 twin optocoupler mast was installed on the first three boats. Tales subsequently received contracts to equip the remaining four submarines of this class with CM010 masts in a twin configuration.
The CM010 mast includes a high-definition camera and a thermal imager, while the CM011 has a high-definition camera and a brightening camera for underwater surveillance, which is not possible with a traditional thermal imager. In accordance with the contract received in 2004, Tales began delivery of CM010 masts in May 2007 Japanese company Mitsubishi Electric Corporation for installation on new Japanese diesel-electric submarines ‘‘Soryu’. Tales is currently developing a low-profile version of the CM010 with the same functionality, as well as a sensor kit consisting of a high-resolution camera, a thermal imager, and a low-light TV camera (or rangefinder). This sensor kit is supposed to be used for special tasks or diesel-electric submarines of smaller dimensions. The ULPV (Ultra-Low Profle Variant), designed for installation on high-tech platforms, is a two-sensor array (high-definition camera plus thermal or low-light camera) mounted in a low-profile sensor head. Its visual signature is similar to that of a commander's periscope up to 90 mm in diameter, but the system is stabilized and has electronic support.
The Japanese diesel-electric submarine "Hakuryu", belonging to the class "Soryu", is equipped with a Thales CM010 mast. The masts were delivered to the shipyard of Mitsubishi, the main contractor of the Soryu-class submarines, for installation on board these submarines.
panoramic mast
The US Navy, the largest operator of modern submarines, is developing periscope technology as part of its Afordable Modular Panoramic Photonics Mast (AMPPM) program. The AMPPM program began in 2009, and as defined by the Naval Research and Development Department, which oversees the program, its goal is "to develop a new sensor mast for submarines that has high-quality sensors for panoramic search in the visible and infrared spectra, as well as shortwave infrared and hyperspectral sensors for long-range detection and identification.” According to the FDA, the AMPPM program should significantly reduce the cost of production and maintenance through a modular design and fixed support. In addition, a significant increase in availability is expected compared to current optocoupler masts. In June 2011, a prototype mast designed by Panavision was selected by the FDA for the AMPPM program. Initially, at least two years of testing on land will take place. This will be followed by sea trials, which are scheduled to begin in 2018. New AMPPM fixed masts with 360-degree all-round visibility will be installed on Virginia-class nuclear submarines.
Materials used:
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www.thalesgroup.com
www.navsea.navy.mil
www.wikipedia.org
en.wikipedia.org
PERISCOPE, optical instrument, which makes it possible to consider objects located in horizontal planes that do not coincide with the horizontal plane of the observer's eye. It is used on submarines for observing the surface of the sea when the boat is submerged, in the land army for safe and invisible observation of the enemy from protected points, in technology for studying inaccessible internal parts of products. In its simplest form, a periscope consists of a vertical tube (Fig. 1) with two mirrors S 1 and S 2 inclined at an angle of 45 ° or prisms with total internal reflection, located parallel to each other at different ends of the tube and facing each other with their reflective surfaces . However, the reflective system of the periscope can be designed differently. The system of two parallel mirrors (Fig. 2a) gives a direct image, the right and left sides of which are identical with the corresponding sides of the observed object.
A system of two perpendicular mirrors (Fig. 2b) gives an inverse image, and since it is viewed by an observer with his back to the object, the right and left sides change their places. Reversing the image and shifting the sides is easy to achieve by placing a refracting prism in the system, but the need to observe with the back to the object, and hence the difficulty in orientation, remains, and therefore the second system is less suitable. The disadvantages of the periscope shown in Fig. 1 and used in positional warfare, are an insignificant angle of view α (about 10-12 °) and a small aperture ratio, which forces us to limit ourselves to a length of no more than 1000 mm with a relatively large diameter of the pipe - up to 330 mm. Therefore, in a periscope, the reflective system is usually associated with a lens system. This is achieved by attaching one or two telescopes to the periscope reflection system. Moreover, since an ordinary astronomical tube gives an inverse image with displaced sides, a combination of perpendicular mirrors with such a tube will give a direct image with correctly located sides. The disadvantage of such a system is the position of the observer with his back to the subject, as mentioned above.
Attaching an astronomical tube to a system of parallel mirrors is also impractical, since the image will turn upside down, with the sides turned. Therefore, a system of parallel mirrors and a terrestrial spotting scope, which gives a direct image, are usually connected in a periscope. However, the installation of two astronomical tubes after two inversions will also give a direct image, which is why it is also used in the periscope. Pipes in this case are arranged with lenses to each other. The refractive system of the periscope does not present any features compared to the telescope, however, the choice of one or another combination of telescopes (more precisely, lenses), their number and focal length is determined by the required angle of view and aperture ratio of the periscope. In the best periscopes, image brightness decreases by ≈30% depending on the system and lens grade.
Since the clarity of the image also depends on the color of objects, an improvement in visibility is also achieved by using color filters. In the simplest form of a periscope (Fig. 3), the upper lens O 1 gives a real image of the object at point B 1, refracting the rays reflected by the prism P 1 . The converging lens U creates at point B 2 also a real image of the object, which is reflected by the prism P 2 and viewed through the eyepiece O 2 by the eye of the observer. Achromatic lenses are usually used in tubes, and measures are taken to eliminate other aberrational distortions. By installing two telescopes one after the other, acting as described above, it is possible to increase the distance between the prisms without compromising the aperture ratio of the periscope and its field of view. The simplest periscope of this type is shown in Fig. 4. Already the first periscopes of this type gave a field of view of 45 ° and an increase of 1.6 with an optical length of 5 m with a tube diameter of 150 mm.
Because observation with one eye is tiring, then periscopes were proposed that give an image on frosted glass, however, this image significantly lost clarity, and therefore the use of frosted glass in periscopes was not widespread.
The next step in the development of the idea of periscopes were attempts to eliminate the need to turn the periscope tube when viewing the horizon at 360 °. This was achieved by connecting several (up to 8) periscopes on one pipe; a corresponding part of the horizon was examined through each of the eyepieces, and the observer had to bypass the pipe. This kind of multiplier periscopes did not yet give the whole picture as a whole, and therefore omniscopes were proposed, giving the entire horizon in the form of an annular picture due to the replacement of the lens with a spherical refractive surface. This kind of devices, differing in considerable complexity, did not provide an increase in the vertical field of view, which prevented the observation of aircraft, and distorted the image, and therefore fell into disuse. More successful was the strengthening of the optical system in the inner tube, which could rotate inside the outer tube, regardless of the latter (Fig. 5).
Panoramic periscopes of this kind, or kleptoscopes, require some additional optical device. The light beam, penetrating into the head of the periscope through a spherical glass cover H, which protects the device from water ingress and does not play an optical role, propagates through the optical system P 1, B 1, B 2, etc., which is fixed in the inner tube J. The latter rotates with the help of a cylindrical gear, shown at the bottom of the device by the handle G, regardless of the outer casing M. In this case, the image falling on the lens B 3, refracted by the prism P 2 and viewed by the eyepiece, will rotate around the light axis of the eyepiece. To avoid this, a quadrangular prism D is fixed inside the inner tube, rotating about the vertical axis with the help of a planetary gear K 1, K 2, K 3 at half speed and straightening the image.
The optical nature of the device is clear from FIG. 6 showing how the rotation of the prism rotates the image at twice the speed. An increase in the field of view in the vertical direction from 30 ° in a conventional periscope to 90 ° is achieved in an anti-aircraft periscope by installing a prism in the objective part of the device that rotates about the horizontal axis, regardless of the rotation of the entire upper part about the vertical axis to view the horizon. The optical part of a periscope of this type is shown in Fig. 7.
Periscopes are used on submarines for two purposes: observation and control of torpedo fire. Observation may consist of simple orientation in the environment and a more careful examination of individual objects. For observation, objects b. visible in full size. At the same time, it has been practically established that for accurate reproduction with monocular observation of objects that are usually observed binocularly with the naked eye, the increase in the device should be. more than 1.
Currently, all submarine periscopes have a magnification of 1.35-1.50 for simple orientation. For a careful examination of individual objects, the increase should be. more, with the maximum possible illumination. Currently, an increase in X 6 is used. periscopes are subject to a double requirement regarding the increase of the device. This requirement is satisfied in bifocal periscopes, the optical part of the objective of which is given in Fig. eight.
The change in magnification is achieved by rotating the system by 180°, while the O 1 lens and the K 1 lens do not move. For a larger increase, the system V’ 1, P "2, V’ 2, for a smaller one - the system V 1, P 1, V 2. Appearance the lower part of the anti-aircraft bifocal periscope is given in Fig. 9.
The described construction for changing the magnification is not the only one. More simply, the same goal is achieved by removing unnecessary lenses from the optical axis of the device, mounted in a frame that can be rotated around the axis at will. The latter is designed vertically or horizontally. For direction finding of objects, determining their distance, course, speed, and for controlling torpedo fire, periscopes are equipped with special devices. In FIG. 10 and 11 show the lower part of the periscope and the observed field of view for a periscope equipped with a vertical baseline rangefinder.
In FIG. 12 shows the field of view of the periscope for determining the distance and heading angle according to the principle of alignment.
In FIG. 13 shows the lower part of a periscope equipped with a photographic camera, and FIG. 14 - the lower part of the periscope with a device for controlling torpedo fire.
The head of the periscope, when moving, causes waves on the surface of the sea, which make it possible to establish the presence of a submarine. To reduce visibility, the head of the periscope is made as small as possible in diameter, which reduces the aperture ratio of the periscope and requires overcoming significant optical difficulties. Usually narrow suit only upper part pipes, gradually expanding it downwards. The best modern periscopes with a pipe length of more than 10 m and a diameter of 180 mm have an upper part about 1 m long with a diameter of only 45 mm. However, at present, experience has established that the discovery of a submarine is achieved not by detecting the periscope head itself, but by the visibility of its trace on the surface of the sea, which persists for a long time. Therefore, at present, the periscope is protruded above the sea surface periodically for a few seconds, necessary for the observation, and immediately hidden until it reappears after a certain period of time. The wave formation caused in this case is much closer to the usual wave of sea water.
The difference in temperature in the pipe and in the environment, combined with the humidity of the air inside the periscope, leads to fogging of the optical system, to eliminate which devices are arranged to dry the periscope. An air tube is installed inside the periscope, drawn into the upper part of the pipe and coming out at the bottom of the periscope. On the other side of the latter, a hole is made from which air is sucked out of the periscope and enters a filter charged with calcium chloride (Fig. 15), after which it is forced into the upper part of the periscope by an air pump through the inner pipe.
Periscope tubes must meet special requirements for strength and rigidity, in order to avoid damage to the optical system; in addition, their material should not affect the magnetic needle, which would disrupt the operation of ship compasses. In addition, pipes should be especially resistant to corrosion in sea water, because in addition to the destruction of the pipes themselves, the tightness of the connection in the stuffing box through which the periscope extends from the boat hull will be violated. Finally, the geometric shape of the pipes must be particularly precise, which, given their long length, creates significant difficulties in production. The usual material for pipes is low-magnetic stainless nickel steel (Germany) or special bronze - immadium (England), which has sufficient elasticity and rigidity.
Strengthening the periscope in the hull of the submarine (Fig. 16) causes difficulties, depending both on the need to prevent the ingress of sea water between the periscope tube and the hull of the boat, and on the vibration of the latter, disturbing the clarity of the image. The elimination of these difficulties lies in the design of the stuffing box, sufficiently waterproof and at the same time elastic, securely connected to the hull of the boat. The pipes themselves must have devices for quickly raising and lowering them inside the boat hull, which, with a periscope weighing hundreds of kg, leads to mechanical difficulties and the need to install motors 1 that rotate winches 2, 4 (3 - switching on for the middle position, 5 - manual drive , 6, 7 - handles for the clutch mechanism). When the tube is raised or lowered, observation becomes impossible because the eyepiece moves rapidly vertically. At the same time, the need for observation is especially great when the boat emerges. To eliminate this, a special platform is used for the observer, connected to the periscope and moving with it. However, this causes an overload of the periscope tubes and the need to allocate a special shaft in the ship's hull to move the observer. Therefore, a stationary periscope system is more often used, which allows the observer to maintain his position and not interrupt his work while the periscope is moving.
This system (Fig. 17) dismembers the ocular and objective parts of the periscope; the first remains motionless, and the second moves with the pipe vertically. For their optical connection, a tetrahedral prism is installed at the bottom of the pipe, and so on. the light beam in the periscope of this design is reflected four times, changing its direction. Since the movement of the tube changes the distance between the lower prism and the eyepiece, the latter intercepts the light beam at its various points (depending on the position of the tube), which violates the optical unity of the system and leads to the need to include another movable lens that regulates the beam rays according to the position of the pipe.
Typically, at least two periscopes are installed on submarines. Initially, this was caused by the desire to have a spare device. At present, when two periscopes of different designs are required - for observation and attack, the periscope used in the attack is at the same time a spare in case one of them is damaged, which is important for performing the main task - observation. Sometimes, in addition to the indicated periscopes, a third, spare, is used exclusively in case of damage to both main ones.
Army periscopes are more simple in design compared to naval ones, while maintaining the main features and improvements of the device. Depending on the purpose, their design is different. An ordinary trench periscope consists of a wooden pipe with two mirrors (Fig. 1). More complicated is the arrangement of the periscope tube, which includes an optical refractive system, but does not differ in special dimensions; such a tube is usually arranged on the principle of a panoramic periscope (Fig. 18).
The dugout periscope (Fig. 19) is similar in design to the simplest marine type and is intended for making observations from shelters.
The mast periscope is used to observe distant objects or in the forest, replacing uncomfortable and bulky towers. It reaches a height of 9-26 m and consists of a mast that serves to strengthen the optical system, mounted inside two short pipes of large diameter. The eyepiece tube is mounted on a carriage at the bottom of the mast, and the objective tube is mounted on the retractable top of the mast. Thus, in this type there are no intermediate lenses, which, despite a significant increase (up to x 10), at a low position of the mast, causes a decrease in the latter as the mast extends, with a simultaneous decrease in image clarity. The mast is mounted on a special carriage, which also serves to transport the device, and the mast moves. The carriage is quite stable and only in strong winds requires additional fastening with bends. The periscope is successfully used in engineering to examine holes drilled in long forgings (shafts, tool channels, etc.), to check for the absence of shells, cracks, and other defects. The device consists of a mirror located at an angle of 45° to the channel axis, mounted on a special frame and connected to an illuminator. The frame moves inside the channel on a special rod and can rotate around the axis of the channel. The telescopic part is mounted separately and placed outside the forging under study; it serves not to transmit an image, as in an ordinary periscope, but to better examine the field of view captured by the periscope.
