Karbonn A30 smartphone now available in India

Every time Karbonn is trying to go big. And the amazing thing is that they keep the prices very low and competitive. This time Karbonn has come up with a new smartphone, named as Karbonn A30. This smartphone is very powerful and runs on the latest Android O.S available in the market.

Specifications of Karbonn A30:

Hardware, O.S, size of Karbonn A30:

• Consists of 1GHz dual core processor.
• Has an accelerometer sensor.
• Runs on Android 4.0.4, i.e. Android Ice cream sandwich.
• Have dimensions of: 166 x 91 x 10.7 mm.
• This smartphone weighs 281g.
• GPU is also integrated with processor for better gaming experience.

Karbonn A30 display type and size:

• 5.9 inches capacitive touch-screen.
• Displays 256k colors.
• Has pixel density of 160.
• Support for multi-touch.

Karbonn A30 image review

Karbonn A30 camera specs:

• Has dedicated main camera of 8 megapixels.
• This camera can take pictures of 3264 x 2448 pixels.
• This camera also has auto focus since LED flash is included with main camera.
• It can record HD videos as well.
• The secondary camera is 1.3 megapixels.
• It is useful to make video calls and making VoIP calls.

Karbonn A30 connectivity options:

• It is dual SIM smartphone.
• Both the SIM’s are mini SIM.
• It includes 2G as well as 3G network.
• Internet options, 2G: GPRS, EDGE options are available.
• It has 3G networks, i.e. HSDPA up to speeds of 7.2 mbps.
• Also includes Wi-Fi connectivity. Wi-Fi is Wi-Fi 802.11 b/g/n.
• It also supports Wi-Fi tethering, which means it can be used Wi-Fi hotspot.
• Bluetooth v4.0. Supported files by Bluetooth are: A2DP, AVRCP, DUN, FTP, HFP, HSP, OPP and SPP.
• 3.5 mm head phone jack for connecting your favorite headphones.
• There is also GPS with A-GPS and Google maps for navigation purposes.
• One USB port is also included.

Karbonn A30 multimedia features:

This smartphone can play MP3/AAC/WMA/WAV format audio files and MP4/WMV/H.264/H.263 format video files. It is capable of playing full HD videos smoothly. It is good entry phone to enjoy Android O.S with ease. Also, it is dual SIM phone. Note that it does not have dual stand-by. Instead it uses Active swap technology just like Samsung galaxy grand launched recently.

Karbonn A30 battery backup:

This phone is powered by 2500 mAh Lithium ion battery. It is enough to provide talk-time of 10 hours on 2G network and 4 hours on 3G network. However, you may not expect long battery if you are browsing web using Wi-Fi. This much battery is enough to last for a day. It provides a stand-by time of 600 hours.

Karbonn A30 memory options:

The Karbonn A30 will be coming with 4 GB of internal memory and 1024 MB of RAM. Out of these, approximately 2.5 GB memory is accessible to user. But this is not the only memory. You can expand the memory as and when required thorugh the micro SD card slot up to 32 GB.

Karbonn A30 price, availability:

Karbonn A30 is now available everywhere in India. The sales pack of Karbonn A30 contains the smartphone, battery, additional black color panel (default panel is silver color), carrying case, charger, headphone and user guide. All this on Flipkart only for 11900/- rupees! You can purchase it online through Flipkart. It will be delivered at your doorstep for free, no delivery charges with an option to pay cash on delivery! 

   

Spice Stellar Pinnacle Mi-350 in India for Rs. 13,999

S Mobility Limited, India’s leading mobile internet company launched their dual SIM android smart phone – the Stellar Pinnacle Mi-530 on 30 January 2013. Stellar Pinnacle Mi-530 by Spice is an dual SIM Android Smart phone device which runs on Android 4.0 Ice Cream Sandwich but has fool-proof plan for upgradation to Jelly Bean. The unique feature that makes it different from other dual sim Androids is that both the SIM can support 3G.

The Mi-530 features a 5.3-inch (13.46 cm) qHD display largest ever on a Spice mobile which offers a rich viewing experience. The Spice Mi -350 runs by a 1.2 Ghz Dual Core processor and 1 GB RAM. It has 16 GB internal memory with an option to expand up to 32 GB via a microSD card slot.

It also features a 8MP rear camera with autofocus, Panorama, Face Detection options. Stellar Pinnacle Mi-350 bags the first position for a smart phone to feature a 5MP front facing camera with auto-focus. It is powered by a 2550mAh Li-ion-Polymer battery which is claimed to be having a talk-time of more than 4 hours.

The IPS (In Plane Switching) display of the Spice Stellar Pinnacle Mi-530 has great contrast as well as colour vibrancy. The maximum brightness supported by the display makes it a perfect device to be used even in bright sunlight as well. The native resolution supported by the device is 960 x 540 pixels. Its 5.2 inch display, with this resolution, makes it a great device to watch HD movies as well as to play HD games 

Camera and Multimedia

The 8 megapixel camera on the Spice Stellar Pinnacle Mi-530 offers average image quality but can record HD 720p videos at 30 frames per second. The camera although features an auto focus lens, gets crooked at times. The camera is supplemented with a dual LED flash that provides ample illumination for image capture under low lights.

The image quality of the camera is good outdoors while indoor mode photography is better to be avoided. The LED flash comes in to play wherever needed but is only effective for close objects and it tends to give the subjects a yellowish hue too

Another major plus for the Spice Stellar Pinnacle Mi-530 is its 5 megapixel front facing camera that features an autofocus lens as well. The 5 megapixel camera is the highest ever front facing camera to have been used for any low cost device or for that matter even the costlier devices as well.

On multimedia front, this device features support for all generic formats. One can also download music applications from the Google Play store to play music and video files in other formats. The loudspeaker however is a bit of a downer for the device. The sound although is average but it gets distorted at high levels for sure

Battery backup

It is yet another plus for the Spice Stellar Pinnacle Mi-530. The device can lasts for 1.5 day between charges easily and even longer for light users. The device manages power usage quite brilliantly and offers superior performance on demand as well. Overall the battery backup of this big screen device is good. The added weight of the bigger battery tends to make the device a bit heavier but with the added talk time, one should not mind the added bulk.

No More Cracked Phones: Samsung’s Awesome Flexible Phone Screen

Samsung has shown off a radical 'bending' mobile phone that could be virtually unbreakable.

The Korean electronics company provided a glimpse of such a device at a keynote speech Wednesday at the International CES gadget show in Las Vegas. 

The screen is expected to find its way in to Samsung handset, although the firm said the devices shown, which ran Microsoft's phone software, were only prototypes.

SAMSUNG GALAXY GRAND:-

 Best Buy Rs. 21,500/-* 

The Galaxy Grand is Samsung’s attempt to woo those who can’t afford a top-end device like the Galaxy Note II. It costs Rs 21,500, which is almost twice as expensive as its low-cost rivals, but it’s the most-affordable option if you’re looking for a device from a tier 1 brand. Currently, the Galaxy Grand doesn’t face any competition from other tier 1 brands, but you may want to know how much better it is than the low-cost devices that offer similar specifications. Here’s a breakdown of the specifications to give you an idea how it compares with the closest competition.  

12.7cm Large Screen

Jelly Bean OS

Powered by Android™ 4.1.2 (Jelly Bean), the latest version of the world’s most popular smartphone operating system. Jelly Bean has fast, fluid and smooth graphics along with a new Google Search™ experience featuring Google Now™

Dual SIM

Multi Window

8MP Camera

Enjoy effortless photo-taking with a high response camera with quick start-up and zero shutter lag.

Xperia™ Z Experience the best of Sony in a smartphone Introducing the precision engineered full HD smartphone:-

Display:-

A screen as impressive as HDTV – Full HD Reality Display

Feel like you’re there with the razor sharp and super bright full HD screen. Xperia Z brings you the highest level of HD available – 1080 progressive scan, for incredibly crisp pictures and no jagged edges. Expertise from our BRAVIA® TV engineers goes into our mobile screens, to bring you the same quality you’d expect from a top quality HDTV. The 5” full HD Reality Display also has very high pixel density – 443 pixels per inch, for razor sharp pictures – and superior brightness. And with the wide colour gamut it gives you the widest colour spectrum, so you can view every detail in vivid colour.

True Screen intelligence – Mobile BRAVIA® Engine 2

The second generation of our acclaimed Mobile BRAVIA® Engine, Mobile BRAVIA® Engine 2 delivers an even better viewing experience by adding new real-time contrast optimisation to the sharpness enhancement, high-quality colour management and noise reduction. Mobile BRAVIA® Engine 2 is also able to analyse content type and adjust the image accordingly. Adding Mobile BRAVIA® Engine 2 to the Reality Display makes for an intelligent screen – one that adapts automatically to display your content in the best way.

(1) Contrast enhancement

Contrast in images and video is enhanced by making the darkest parts slightly darker, which brings out details in the picture.

(2) Colour Management

Colour saturation is increased for specified colour ranges, which makes the colours deeper and more vivid. And the intelligent Mobile BRAVIA® Engine 2 software reproduces skin colour exactly as it appears to the naked eye.

Camera:-

Exmor RS™ for mobile – the world’s first image sensor with HDR video for smartphones

HDR for photos and videos captures natural colours in any light. HDR (High Dynamic Range) is an imaging technology used to capture clear photos against strong backlight. With HDR, the camera captures the same image at different exposure levels and layers them to create one optimised photo.

Xperia Z introduces HDR to video, so that you can film even in high contrast situations, like in front of a window or with the sun behind your subject.

Always the right setting – Superior Auto

Now it’s always easy to get a great shot. With Superior Auto, you don’t have to know the ins and outs of camera settings to make use of them. In Superior Auto mode, the camera combines Scene Recognition with high quality and high performance image processing technology (HDR and noise reduction) to automatically shoot with the optimal settings. And your device is automatically optimised for 36 different scenes, so you always get the best shot.

Stunning shots in any light — 13 MP camera with Exmor RS™ for mobile

The 13 megapixel camera is built with the same modules as leading Sony cameras. Exmor RS™ for mobile is an evolution of our Sony image sensor technology, with a next-generation BSI light sensor. By adopting the technology of luminance and colour noise reduction, we’ve created a camera that snaps highly detailed shots with low noise – even in challenging lighting conditions. You’re now also able to reproduce objects in more vivid colours and capture night images and faces in stunning clarity. Exmor RS™ for mobile includes HDR video, for clear shots even when your subject is backlit.

(1) Without Exmor RS™ for mobile

(2) With Exmor RS™ for mobile

World’s only dual Exmor R for mobile camera

We’ve included the Sony Exmor R™ for mobile sensor on the full HD front camera, so you can take self-portraits or chat in lowlight conditions as well. And both the front and rear cameras support HDR photos.

Minimal yet distinctive – OmniBalance design

With Xperia Z, we introduce our new OmniBalance design. The design is focused on creating balance and symmetry in all directions. Xperia Z has subtly rounded edges and smooth, reflective surfaces on all sides, which are held together by an innovative skeleton frame.

Both the front and back are made of glass, with a seamless surface. Together with enhanced reflection coating on the top, bottom and sides, Xperia Z actually mirrors the world around you. OmniBalance design balances technology vs. design, letting you get so totally immersed in the content that the hardware disappears.

Quality craftsmanship

Xperia Z was designed in collaboration with Sony consumer electronics experts, for quality craftsmanship and consistent attention to details. Only premium materials were used throughout, like aluminium for the power and volume buttons and durable tempered glass for the front and back.

Water and dust resistant

We tested this Android mobile to make sure it can keep going even after 30 minutes under water. It can even withstand water jets. The high IP55 & IP57 rating means you can use it in the rain, take photos by the pool and easily clean it off from everyday spills and dirt.

We even put Xperia Z in a dust chamber for rigorous testing, to make sure its operations were unaffected.

Quick benefits:

• Water resistant up to 1 meter
• Resistant to water jetsQuicbenefits:
  • Water resistant up to 1 meter
  • Resistant to water jets
  • Dust resistant
• Dust resistant

SAMSUNG LAUNCH S4:-

           

Samsung Galaxy S IV

   

Samsung Galaxy S4 Screen

If you thought the Samsung Galaxy S3 was big enough already, the Galaxy S4 screen may be step too far. It's reported to feature a 5-inch 1080p screen, in-line with the recently-unveiled Sony Xperia Z, ZTE Grand X and Huawei Ascend D2. However, Samsung is likely to optimise the design, reducing the bezel so that the body isn't much, if at all, larger. 

Consistent with the rest of the Galaxy flagships, the Samsung Galaxy S4 will use an AMOLED display, rather than the IGZO type expected in the iPhone 5S. AMOLEDs offer unparalleled contrast, but often struggle to supply enough brightness for dazzling sunlight.

Samsung Galaxy S4 Specs and CPU

Like clockwork, the Samsung Galaxy S4 will feature an eight-core processor. The first Galaxy S used a single core CPU, the second a dual, the Galaxy S3 a quad – so this news makes perfect sense. 

Four of the cores are “performance” A15 cores, and the other four battery-saving A7-design cores. Samsung claims that it'll use up to 70 per cent less power than previous-generation chips, which should mitigate the additional power consumption of a 1080p-resolution screen.

The Samsung Galaxy S4 is also likely to feature 2GB of RAM, much like the Samsung Galaxy Note 2. 4GB RAM phones will come in time, but at present any more than 2GB is arguably overkill.

Samsung Galaxy S4 Software

The Samsung Galaxy S4 will, of course, run Android. It'll feature Android 4.2 along with the latest version of Samsung's TouchWiz UI. 

Most interesting points of speculation here are quite what extra bells and whistles Samsung will incorporate in its new custom UI – TouchWiz 6.0. At present we haven't a clue what it'll offer, but expect more photo and video modes and more integration of gestures, possibly under the “S” banner. Gestural input and the “S” term came together with the Galaxy Note and its S Pen stylus.

Samsung Galaxy S4 Features

The one dramatic change we doubt whether Samsung will implement is a digitiser layer, as seen in the Galaxy Note 2. That there's talk of a Galaxy Note 3 suggests the Galaxy S4 will not have a digitiser, as it's the key defining characteristic between the two ranges. Think the next Galaxy should feature a digitiser? Drop up a comment below.

Other noteworthy features are ones that are practically guaranteed – 4G mobile data connectivity and NFC wireless connectivity. We also expect the Samsung Galaxy S4 to keep its microSD memory card slot, like every flagship in the series to date.

Samsung Galaxy S4 Camera

We thought the megapixel race was over – but perhaps not. The Samsung Galaxy S4 will have a 13-megapixel camera according to recent rumours. Simply adding more megapixels does not result in better images, but Samsung is one of the best makers of mobile phone cameras. It has been top of its game for years now. Can Samsung really pull off a 13-megapixel snapper, though?

A leaked photo taken using the camera suggest Samsung is making the right moves. Although the photo is barely worth glancing at as a purely visual thing, its EXIF data is quite interesting. It reveals the Samsung Galaxy S4 has an f/2.2 lens. Most notably, that's superior to the f/2.4 lens of the Sony Xperia Z, one of the most advanced phone cameras on the market at the moment.

HERE IS THE MICROMAX CANVAS 2:-A110

 Micromax was first to market with a 5-inch, budget phablet — the A100 Canvas smartphone.

The A110 Canvas 2 is its successor and features several hardware and design upgrades. The phone is overall slimmer (9.7mm vs 11.9mm), even though the weight remains unchanged at 168 grams. It now has a dual core processor instead of the single core on the A100 and the camera is upgraded to 8MP with dual LED flash (compared to 5MP with single LED flash.

Below the screen is a physical home key along with back and menu touch keys. And on the bottom of the phone has a USB/charging connector with a mouthpiece alongside it. On the top of the device is a 3.5 mm earjack whereas, the left side gives you volume controls and lanyard eyelet. The right side holds the lock/power key but lacks with the dedicated camera key on the phone. Above the screen is a front facing camera with light sensors and earpiece. On the back of the phone is a great 8 megapixels camera with dual LED flash and speaker grill on the bottom. The overall construction of the Canvas 2 is great and it’s handy too.

Interface/OS:

Micromax A 110 primarily runs on Google Android 4.0 ICE (ice cream sandwich) operating system, which has done full justice with the device and to its buyers. The phone is power packed with Dual Core 1 GHz MediaTek MT 6577 processor. When tested, the browsing on this interface with power packed processor and RAM was a better experience. The speed was good when on 3G and multitasking to swapping applications was smoother.

Battery:

For everlasting experience, the Canvas 2 A 110 comes with a standard Li-Ion 2000 mAh battery which goes well with the device. When tested, battery performed excellent results on 2G and above average on 3G. The stand by time delivered was up to 180 hours on 2G and up to 145 hours when on 3G whereas, the talk time was up to 5 hours on 2G and up to 4 hours on 3G. So, we can say that Micromax A 110 ensures average battery results.

Camera:

Canvas 2 A 110 comes with tremendous 8 megapixels main camera with auto focus and dual LED flash and it also has a VGA front facing camera. The camera quality of Micromax A 110 is great. When tested, the outdoor images captured were rich and clearer in colours and the camera worked quickly and hardly took a second to be ready for next image. The Canvas 2 camera supports JPEG, PNG, GIF, WBMP, BMP and AGIF image type. The indoor shoots were even good. The A 110 camera has a 3264 x 2448 image resolution. The images from front camera were average.

Memory:
The Micromax Canvas 2 A 110 comes with in built memory of 4 GB, from which 2 GB is user available memory. The memory can further be extended to 32 GB using a micro SD card. The phone supports 512 MB RAM space.
Audio/Video:
The Micromax A 110 has not compromised with its voice/sound quality. The sound quality when tested was good with headphones and even when on speaker mode. T Micromax Canvas 2 A 110 supports MP3, AAC, AAC+, e AAC+, AMR, WB-AMR, MIDI, Ogg Vorbis and PCM audio formats. Like other smartphones, Canvas 2 also has a Stereo FM radio. The video quality of this phone is wonderful. It features 1080 pixels full HD recording and playback at 30 frames per second. The video call quality from its VGA front facing camera is good but the sound quality drops down if you hold it at a hand’s distance. It supports MPEG4, H.264, H.263 video formats. When tested, the video captured from the camera was in superior quality and gave 480 x 854 pixels resolution.
Features:
Dual SIM service of this phone allows you to receive calls while you are connected to the internet or even if you are already talking on the phone on the other SIM card. The Micromax Canvas 2 A 110 is pre loaded with SNS integration. It includes all major social sites like, Facebook, twitter, You Tube, Linked In and many more. It also offers Google Search, Maps, Gmail, Calendar, and Google Talk like options to the buyers. Wi-Fi direct, Voice Calling and All Share are also featured in this power packed phone.

INDIAN MOBILE COMPANY ROCKS :-MICROMAX LAUNCH CANVAS HD A116

Micromax launches A116 Canvas HD with quad-core processor for Rs. 13,990

Micromax A116 Canvas HD selling 25 units per minute
Micromax has launched its much awaited Micromax A116 Canvas HD smartphone in the Indian market. The smartphone will be available through the company's official website starting February 14, 2013 for Rs. 13,990. The company is claiming that it will take about 5-7 working days to ship this smartphone.

Just to recap, the Micromax A116 Canvas HD is powered by MediaTek's MT6589 quad-core processor that clocks 1.2GHz. It will run on Android 4.1 (Jelly Bean) out of the box. It packs in a 2000mAh battery. Micromax A116 Canvas HD come with 5-inch HD IPS screen that sports 1280x720 resolution and a colour depth of 16.7 million.

For camera, there is an 8-megapixel rear shooter with LED flash and 4X zoom and a VGA front camera. Other features of the smartphone include 1GB RAM and 4GB of internal storage, which can be expanded to up to 32GB via microSD card. It is a dual-SIM smartphone, which supports GSM frequency on both the SIMs.

This smartphone will be competing head-on with the recently launched Karbonn S1 Titaniumsmartphone that is available for Rs. 10,990. This smartphone too has 4.5-inch qHD (960X540) multi-touch capacitive touch display and runs on Android 4.1 Jelly Bean out of the box. It comes with a 5-megapixel autofocus rear camera with LED flash and a VGA front camera.

Internally, Karbonn S1 Titanium is powered by a 1.2GHz quad-core processor with 1GB of RAM and 4GB of internal storage (expandable to up to 32GB via microSD). It is also a dual-SIM smartphone, which comes with 1,600mAh battery. 

Micromax A116 Canvas HD specifications

• 5-inch (1280 x 720 pixels) HD IPS display
• 1.2 GHz quad-core MediaTek MT6589 processor
• 1GB RAM
• 4GB internal memory, expandable up to 32GB
• 8-megapixel rear camera
• VGA front camera
• Dual-SIM (GSM+GSM)
• 2000 mAh battery
• Android 4.1

SEMI CONDUCTOR LASER:-

A laser diode is an electrically pumped semiconductor laser in which the active medium is formed by a p-n junction of a semiconductor diode similar to that found in a light-emitting diode. The laser diode is distinct from the optically pumped semiconductor laser, in which, while also semiconductor based, the medium is pumped by a light beam rather than electric current.
A laser diode is formed by doping a very thin layer on the surface of a crystal wafer. The crystal is doped to produce an n-type region and a p-type region, one above the other, resulting in a p-n junction, or diode.
Laser diodes form a subset of the larger classification of semiconductor p-n junction diodes. Forward electrical bias across the laser diode causes the two species of charge carrier – holes and electrons – to be "injected" from opposite sides of the p-n junction into the depletion region. Holes are injected from the p-doped, and electrons from the n-doped, semiconductor. (A depletion region, devoid of any charge carriers, forms as a result of the difference in electrical potential between n- and p-type semiconductors wherever they are in physical contact.)
example:-
               cd player lens.

HELIUM NEON LASER:-

A helium–neon laser or HeNe laser, is a type of gas laser.

This laser contain helium and neon in the ratio of 7:1.In the presence of 1mm of pressure of mercury.it is 0.5 m in diameter.

Principle : He-Ne laser works on the principle of stimulated emission.

population inversion is essential for stimulated emission.....Population inversion is the phenomenon ofhaving more atoms in higher energy

level than lower energy level. The photons emitted through stimulated emission are same in energy, frequency and phase. So, they are highly coherent which is the characteristic of laser.or

The phenomenon of making the atoms in higher energy state more than that in

lower energy state by induced absorption is called population inversion. The process by which population inversion is carried out is called optical pumping.

i.e., N2> N1, at this state the rate of stimulated emission is more as compair to absorption.

Working :

Working :

A high voltage applied across the gas mixture produces electrical breakdown of gas into ions and electrons, these electrons collide with He and Ne atoms and exists them to high energy levels.

The life time of F2 and F3 of He is more therefore these levels of the become density populated than F1. As E4 and E6 levels of Ne are close to excited energy levels of He therefore the provides its energy to atoms of Ne by inelastic collisions. Since pressure of He atom is greater than that of Ne, the levels E6 and E4 of Ne are densely populated than other energy levels.

The life time of F2 and F3 of He is more therefore there levels of the become densely populated than F1. As E4 and E6 levels of Ne are close to excited energy levels of He therefore the provides its energy to atoms of No by inelastic collisions. Since pressure of He atom is greater than that of Ne, the levels E6 and E4 of Ne are densely populated than other energy levels.

Photon with energy hv = E6- E3 stimulate the transition to level E3. During this transition radiation is emitted with wavelength 6328 A. The He-Ne laser can operated at any of prominent wavelength.

The corresponding photons bounce back and forth stimulated the reflecting end faces of tube, which cause stimulated emission during each journey. Those photons travelling along optical axis of cavity get reflected back and forth while others which are at certain angle will be lost. The multiplication process results and large number of photons of same frequency direction and same phase are produced as laser output.

Role of Helium Atom: He is used for selective pumping of upper laser level of Neon. It is superior to Ruby laser because

(I) It commonly use low power hence no cooling arrangement are required.

(ii )Gas lasers are in expensive.

(iii) It is most stable and continous type of laser.

The corresponding photons bounce back and forth stimulated the reflecting end faces of tube, which cause stimulated emission during each journey. Those photons travelling along optical axis of cavity get reflected back and forth while others which are at certain angle will be lost. The multiplication process results and large number of photons of same frequency direction and same phase are produced as laser output.

Role of Helium Atom: He is used for selective pumping of upper laser level of Neon. It is superior to Ruby laser because

(I) It commonly use low power hence no cooling arrangement are required.

(ii )Gas lasers are in expensive.

(iii) It is most stable and continous type of laser.

PROPERTIES OF LASER:-

1.Monochromatic:-

                                laser is monochromatic light. "Monochromatic light" refers to light of a narrow frequency.

 "Monochromatic light" refers to light of a narrow frequency.

2.Intensity:-

                   The intensity is the power transferred per unit area.laser light is concentrated to very small region.

    Therefore 1 watt source laser light is more intense than 100 watt bulb.

3.Coherence:- 

                    Two sources of light are said to be coherent if the waves emitted from them have the same frequency and are 'phase-linked'; that is, they have a zero or constant phase difference.it spread through t spherical wave fronts.There are two types of coherence - spatial and temporal Correlation between the waves at one place at different times, or along the path of a beam at a single instant, are effectively the same thing, and are called "temporal coherence". Correlation between different places (but not along the path) is called "spatial coherence". 

Coherent source (laser)
Incoherent source

4.Directionality:-

                        Laser light radiate in only one direction.while other source radiate in many directions.laser travel more distance as compared to the other ordinary sources.laser is highly directional.

5.Divergence:-

                         lasers are subject to divergence, which is measured in milliradians (mrad) or degrees. For many applications, a lower-divergence beam is preferable. Neglecting divergence due to poor beam quality, the divergence of a laser beam is proportional to its wavelength and inversely proportional to the diameter of the beam at its narrowest point. For example, an ultraviolet laser that emits at a wavelength of 308 nm will have a lower divergence than an infrared laser at 808 nm, if both have the same minimum beam diameter. The divergence of good-quality laser beams is modeled using the mathematics of Gaussian beams.

WHATS IS LASER:-

LASER:-laser stands for light amplification by stimulation emission of radiation.....
When an electron is excited from a lower to a higher energy level, it will not stay that way forever. An electron in an excited state may decay to a lower energy state which is not occupied, according to a particular time constant characterizing that transition. When such an electron decays without external influence, emitting a photon, that is called "spontaneous emission"
                                    but
laser basically works on stimulated emission.....

Stimulated emission:-

 A transition from the higher to a lower energy state, however, produces an additional photon; this is the process of stimulated emission.

Optical fiber:-

An optical fiber is small as our hair.
An optical fiber (or optical fibre) is a flexible, transparent fiber made of glass (silica) or plastic, slightly thicker than a human hair. It functions as awaveguide,  to transmit light between the two ends of the fiber. The field of applied science and engineering concerned with the design and application of optical fibers is known as fiber optics. Optical fibers are widely used in fiber-optic communications, which permits transmission over longer distances and at higher bandwidths (data rates) than other forms of communication. Fibers are used instead of metal wires because signals travel along them with less loss and are also immune to electromagnetic interference.
Optical fibers typically include a transparent core surrounded by a transparent cladding material with a lower index of refraction. Fibers that support many propagation paths or transverse modes are calledmulti-mode fibers (MMF), while those that only support a single mode are called single-mode fibers (SMF). Multi-mode fibers generally have a wider core diameter, and are used for short-distance communication links and for applications where high power must be transmitted. Single-mode fibers are used for most communication links longer than 1,050 meters (3,440 ft). Light is kept in the core by total internal reflection. 
SINGLE MODE FIBER:-

The structure of a typical single-mode fiber.
1. Core: 8 µm diameter
2. Cladding: 125 µm dia.
3. Buffer: 250 µm dia.
4. Jacket: 400 µm dia.
MULTI MODE FIBER:-
:- HERE IS THE PROPAGATION OF LIGHT THROUGH  MULTI MODE FIBER

TOTAL INTERNAL REFLECTION:- 
Total internal reflection is a phenomenon that happens when a propagating wave strikes a medium boundary at an angle larger than a particular critical angle with respect to the normal to the surface. If the refractive index is lower on the other side of the boundary and the incident angle is greater than the critical angle, the wave cannot pass through and is entirely reflected. The critical angle is the angle of incidence above which the total internal reflectance occurs. This is particularly common as an optical phenomenon, where light waves are involved, but it occurs with many types of waves, such as electromagnetic waves in general or sound waves
Cladding is one or more layers of materials of lower refractive index, in intimate contact with a core material of higher refractive index. The cladding causes light to be confined to the core of the fiber by total internal reflection at the boundary between the two. Light propagation in the cladding is suppressed in typical fiber. Some fibers can support cladding modes in which light propagates in the cladding as well as the core.

The numerical aperture of a fiber is a function of the indices of refraction of the cladding and the core by: