A camera phone is a mobile phone which is able to capture still photographs (and usually video). Since early in the 21st century the majority of mobile phones in use are camera phones.[1]
Most camera phones are simpler than separate digital cameras. Their usual fixed focus lenses and smaller sensors limit their performance in poor lighting. Having no physical shutter, most have a long shutter lag. Most have no flash or optical zoom[2] or tripod screw. Many lack a USB connection, removable memory card, or other way of transferring their pictures more quickly than by the phone's inherent communication feature.
Some of the more expensive camera phones have only a few of these technical disadvantages, which apply most acutely in low light conditions and in any case have not inhibited their widespread use. Most model lines improve in these regards every year or two. Some, such as the Droid Incredible only have a menu choice to start an application program to activate the camera.[3] Others, such as the BlackBerry Storm2, Droid X, Motorola V980 and Nokia 5800 also have a separate camera button for quickness and convenience. Some are designed to resemble separate low-end digital compact cameras in appearance and to some extent in features and picture quality, and are branded as both mobile phones and cameras, including certain Sony phones.
The principal advantages of camera phones are cost and compactness; indeed for a user who carries a mobile phone anyway, the additional size and cost are negligible. Smartphones that are camera phones may run mobile applications to add capabilities such as geotagging and image stitching. A few high end phones can use their touch screen to direct their camera to focus on a particular object in the field of view, giving even an inexperienced user a degree of focus control exceeded only by seasoned photographers using manual focus.
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Some camera phones use CMOS image sensors, due to largely reduced power consumption compared to CCD type cameras, which are also used.
Images are usually saved in the JPEG file format, and the wireless infrastructure manages the sharing. The lower power consumption prevents the camera from quickly depleting the phone's battery.
The camera phone, like many complex systems, is the result of converging and enabling technologies. There are dozens of relevant patents dating back as far as 1956. Compared to digital cameras of the 1990s, a consumer-viable camera in a mobile phone would require far less power and a higher level of camera electronics integration to permit the miniaturization.
The CMOS active pixel sensor "camera-on-a-chip" developed by Dr. Eric Fossum and his team in the early 1990s achieved the first step of realizing the modern camera phone as described in a March 1995 Business Week article. While the first camera phones, as successfully marketed by J-Phone in Japan, used CCD sensors and not CMOS sensors, more than 90% of camera phones sold today use CMOS image sensor technology.
Over the years there have been many videophones and cameras that have included communication capability. Some devices experimented with integration of the device to communicate wirelessly with Internet, which would allow instant media sharing with anyone anywhere. For example, in 1995 Apple experimented with the Apple Videophone/PDA.[4] There were several digital cameras with cellular phone transmission capability shown by companies such as Kodak, Olympus in the early 1990s.[5] There was also a digital camera with cellular phone designed by Shosaku Kawashima of Canon in Japan in May 1997.[6]
On June 11, 1997, Philippe Kahn shared instantly the first pictures from the maternity ward where his daughter Sophie was born. He wirelessly transmitted his cell phone pictures to more than 2,000 family, friends and associates around the world. Kahn's wireless sharing software and camera integrated into his cell phone augured the birth of instant visual communications.[7][8] Kahn's cell phone transmission is the first known publicly-shared picture via a cell phone.
In Japan, two competing projects were run by Sharp and Kyocera in 1997. Both had cell phones with integrated cameras. However, the Kyocera system was designed as a peer-to-peer video-phone as opposed to the Sharp project which was initially focused on sharing instant pictures. That was made possible when the Sharp devices was coupled to the Sha-mail infrastructure designed in collaboration with American technologist, Kahn. The Kyocera team was led by Mr. Kazumi Saburi.[9]
Cameras on cell phones proved popular right from the start, as indicated that the J-Phone in Japan had more than half of its subscribers using cell phone cameras in two years. The world soon followed. By 2003, more camera phones were sold worldwide than stand-alone digital cameras. In 2005, Nokia became the world's most sold digital camera brand. In 2006, half of the world's mobile phones had a built-in camera.
In 2008, Nokia sold more camera phones than Kodak sells film based simple cameras, thus became the biggest manufacturer of any kind of camera.
In 2010, the worldwide number of camera phones totaled more than a billion,[10] and sales of separate cameras began to decline.
By 2010, most mobile phones, even inexpensive ones, were being sold with a camera. High end camera phones usually have a good lens, high resolution, but a small sensor.
Twelve-megapixel camera phones have been produced by at least two companies.[11][12] To highlight the capabilities of the Nokia N8(Big CMOS Sensor) camera, Nokia created a short film, The Commuter, in October 2010. The seven-minute film was shot entirely on the phone's 720p camera. A 14 megapixel smartphone with 3x optical zoom was announced in 2010.[13]
In 2006, Thuraya released the first satellite phone with an integrated camera. The Thuraya SG-2520 is manufactured by a Korean company called APSI and runs Windows CE.
Camera phones can share pictures almost instantly and automatically via a sharing infrastructure integrated with the carrier network. Early developers of camera phones like Philippe Kahn envisioned a technology that would enable service providers to "collect a fee every time anyone snaps a photo."[7] The resulting technologies, Multimedia Messaging Service and Sha-Mail were developed parallel to and in competition to open Internet based mobile communication provided by GPRS and later 3G networks.
The closed sharing infrastructure was critical and explains the early successes of J-Phone, DoCoMo in Japan, Sprint, and other carriers worldwide.
The first commercial camera phone complete with infrastructure was the J-SH04, made by Sharp Corporation, had an integrated CCD sensor, with the Sha-Mail (Picture-Mail in Japanese) infrastructure developed in collaboration with Kahn's LightSurf venture, and marketed from 2001 by J-Phone in Japan today owned by Softbank.
The first commercial deployment in North America of camera phones was in 2004. The Sprint wireless carriers deployed over one million camera phone manufactured by Sanyo and launched by the PictureMail infrastructure (Sha-Mail in English) developed and managed by LightSurf.
Users of early camera phones were held captive by the MMS business model. While phones had internet connectivity, working web browsers and email-programs, the phone menu offered no way of including a photo in an email or uploading it to a web site. Connecting cables or removable media that would enable the local transfer of pictures were also usually missing.
Modern smartphones have more connectivity and transfer options with photograph attachment features.
Major manufacturers include Toshiba, Sharp, Nokia, Sanyo, Samsung, Motorola, Siemens, Sony Ericsson, and LG Electronics. Resolution is typically in the range of one tenth to one half as many megapixels as contemporary low end compact digital cameras.
Major manufacturers of cameras for phones include Toshiba, ST Micro, Sharp, Omnivision, and Aptina.
During 2003 as camera phones were gaining popularity in Europe some phones without cameras had support for MMS and external cameras that could be connected with a small cable or directly to the data port at the base of the phone. The external cameras were comparable in quality to those fitted on regular camera phones at the time, typically offering VGA resolution.
Phones that supported extra cameras include the Siemens SL55 and Nokia Series 40 phones such as the Nokia 6810. Unfortunately these cameras are not compatible with more recent phones.
These external cameras never proved very popular although they were stocked in various shops at the time.
Personal photography allows people to capture and construct personal and group memory, maintain social relationships as well as expressing their identity.[14] The hundreds of millions[15] of camera phones sold every year provide the same opportunities, yet these functions are altered and allow for a different user experience. As mobile phones are constantly carried, camera phones allow for capturing moments at any time. Mobile communication also allows for immediate transmission of content (for example via Multimedia Messaging Services), which cannot be reversed or regulated.
While phones have been found useful by tourists and for other common civilian purposes, as they are cheap, convenient, and portable; they have also posed controversy, as they enable secret photography. A user may pretend to be simply talking on the phone or browsing the internet, drawing no suspicion while photographing a person or place illegally or against that person's wishes.
As a network-connected device, megapixel camera phones are playing significant roles in crime prevention, journalism and business applications as well as individual uses. They can also be used for activities such as voyeurism, invasion of privacy, and copyright infringement. Because they can be used to share media almost immediately, they are a potent personal content creation tool. On January 17, 2007, New York City Mayor Michael Bloomberg announced a plan to encourage people to use their camera-phones to capture crimes happening in progress or dangerous situations and send them to emergency responders. Through the program, people will be able to send their images or video directly to 911.[16]
Enforcing bans on camera phones has proven nearly impossible. They are small and numerous and their use is easy to hide or disguise, making it hard for law enforcement and security personnel to detect or stop use.
From time to time, organizations and places have prohibited or restricted the use of camera phones and other cameras because of the privacy, security, and copyright issues they pose. Such places include the Pentagon, federal and state courts,[17] museums, schools, theaters, and local fitness clubs. Saudi Arabia, in April 2004, banned the sale of camera phones nationwide for a time before reallowing their sale in December 2004 (although pilgrims on the Hajj were allowed to bring in camera phones). In South Korea and Japan, all camera phones sold in the country must make a clearly audible sound whenever a picture is taken: These laws are intended to reduce the number of up-skirt photos taken.
There is the occasional anecdote of camera phones linked to industrial espionage and the activities of paparazzi, as well as some hacking into wireless operators' network.
Camera phones have also been used to discreetly take photographs in museums, performance halls, and other places where photography is prohibited. However, as sharing can be instantaneous, even if the action is discovered, it is too late, as the image is already out of reach, unlike a photo taken by a digital camera that only stores images locally for later transfer.
In Ireland the annual "RTE 60 second short award" was won by 15 year old Laura Gaynor who made her winning cartoon,"Piece of Cake" on her Sony Ericsson C510 camera phone.
The cameras of smartphones are used as input devices in numerous research projects and commercial applications. A commercially successful example is the use of QR Codes attached to physical objects. QR Codes can be sensed by the phone using its camera and provide an according link to related digital content, usually a URL. Another approach is using camera images to recognize objects. Content based image analysis is used to recognize physical objects such as advertisement posters[19] to provide information about the object. Hybrid approaches use a combination of unobstrusive visual markers and image analysis. An example is to estimate the pose of the camera phone to create a real-time overlay for a 3D paper globe.[20] On recent camera phones it is even feasible to provide an augmented reality overlay for 2D objects[21] and to recognize multiple objects on the phone using a stripped down object recognition algorithm[22] as well as using GPS and compass. Auto-geotagging can show where a picture is taken, promoting interactions and allowing a photo to be mapped with others for comparison.
Camera phones, or more specifically, widespread use of such phones as cameras by the general public, has increased exposure to laws relating to public and private photography. The laws that relate to other types of cameras also apply to camera phones. There are no special laws for camera phones.
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