Camera phone


A camera phone is a mobile phone that is able to capture photographs and often record video using one or more built-in digital cameras. It can also send the resulting image wirelessly and conveniently. The first commercial phone with a color camera was the Kyocera Visual Phone VP-210, released in Japan in May 1999. While cameras in mobile phones used to be supplementary, they have been a major selling point of mobile phones since the 2010s.
Most camera phones are smaller and simpler than the separate digital cameras. In the smartphone era, the steady sales increase of camera phones caused point-and-shoot camera sales to peak about 2010, and decline thereafter. The concurrent improvement of smartphone camera technology and its other multifunctional benefits have led to it gradually replacing compact point-and-shoot cameras.
Most modern smartphones only have a menu choice to start a camera application program and an on-screen button to activate the shutter. Some also have a separate camera button for quickness and convenience. A few, such as the 2009 Samsung i8000 Omnia II or S8000 Jet, have a two-level shutter button as in dedicated digital cameras. Some camera phones are designed to resemble separate low-end digital compact cameras in appearance and, to some degree, in features and picture quality, and are branded as both mobile phones and cameras—an example being the 2013 Samsung Galaxy S4 Zoom.
The principal advantages of camera phones are cost and compactness; indeed, for a user who carries a mobile phone anyway, the addition is negligible. Smartphones that are camera phones may run mobile applications to add capabilities such as geotagging and image stitching. Also, modern smartphones can use their touch screens to direct their cameras 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. However, the touch screen, being a general-purpose control, lacks the agility of a separate camera's dedicated buttons and dial.
Starting in the mid-2010s, some advanced camera phones featured optical image stabilisation, larger sensors, bright lenses, 4K video, and even optical zoom, for which a few used a physical zoom lens. Multiple lenses and multi-shot night modes are also familiar. Since the late 2010s, high-end smartphones typically have multiple lenses with different functions to make more use of a device's limited physical space. Common lens functions include an ultrawide sensor, a telephoto sensor, a macro sensor, and a depth sensor. Some phone cameras have a label that indicates the lens manufacturer, megapixel count, or features such as autofocus or zoom ability for emphasis, including the Samsung Omnia II or S8000 Jet and Galaxy S II and S20, Sony Xperia Z1 and some successors, Nokia Lumia 1020, Huawei P40 Pro, and Oppo Find X series

Technology

Mobile phone cameras typically feature CMOS active-pixel image sensors due to largely reduced power consumption compared to charge-coupled device type cameras. Some use CMOS back-illuminated sensors, which use even less energy, at a higher price than CMOS and CCD.
The usual fixed-focus lenses and smaller sensors limit performance in poor lighting. Lacking a physical shutter, some have a long shutter lag. Photoflash by the typical internal LED source illuminates less intensely over a much longer exposure time than a flash strobe, and none has a hot shoe for attaching an external flash. Optical zoom and tripod screws are rare, and some also lack a USB connection or a removable memory card. Most have Bluetooth and Wi-Fi and can make geotagged photographs. Some of the more expensive camera phones have only a few of these technical disadvantages, but with bigger image sensors, their capabilities approach those of low-end point-and-shoot cameras. The few hybrid camera phones, such as Samsung Galaxy S4 Zoom and K Zoom, were equipped with real optical zoom lenses.
As camera phone technology has progressed, lens design has evolved from a simple double Gauss or Cooke triplet to many molded plastic aspheric lens elements made with varying dispersion and refractive indexes. Some phone cameras also apply distortion, vignetting, and various optical aberration corrections to the image before it is compressed into a JPEG format.
Optical image stabilization allows longer exposures without blurring, despite trembling. The earliest known smartphone to feature it on the rear camera is in late 2012 on the Nokia Lumia 920, and the first known front camera to feature one is on the HTC 10 from early 2016.
Few smartphones, such as LG initially with the 2014 G3, are equipped with a time-of-flight camera with infrared laser beam assisted auto focus. A thermal imaging camera has initially been implemented in 2016 on the Caterpillar S60.
High dynamic range imaging merges multiple images with different exposure values for a balanced brightness across the image and was first implemented in early 2010s smartphones such as the Samsung Galaxy S III and iPhone 5. The earliest known smartphone to feature high dynamic range filming is the Sony Xperia Z, 2013, where frames are arrayed by changing the exposure every two lines of pixels to create a spatially varying exposure.
As of 2019, high-end camera phones can produce video with up to 4K resolution at 60 frames per second for smoothness.

Zooming

Most camera phones have a digital zoom feature, which may allow zooming without quality loss if a lower resolution than the highest image sensor resolution is selected, as it makes use of image sensors' spare resolution. For example, at twice digital zoom, only a quarter of the image sensor resolution is available. A few have optical zoom, and several have a few cameras with different fields of view, combined with digital zoom as a hybrid zoom feature. For example, the Huawei P30 Pro uses a periscope 5x telephoto camera with up to 10x digital zoom, resulting in 50x hybrid zoom. An external camera can be added, coupled wirelessly to the phone by Wi-Fi. They are compatible with most smartphones. Windows Phones can be configured to operate as a camera even if the phone is asleep.

Physical location

When viewed vertically from behind, the rear camera module on some mobile phones is located in the top center, while other mobile phones have cameras located in the upper left corner. The latter has benefits in terms of ergonomy due to the lower likelihood of covering and soiling the lens when held horizontally, as well as more efficient packing of tight physical device space due to neighbouring components not having to be built around the lens.

Audio recording

Mobile phones with multiple microphones usually allow video recording with stereo audio. Samsung, Sony, and HTC initially implemented it in 2012 on their Samsung Galaxy S III, Sony Xperia S, and HTC One X. Apple implemented stereo audio starting with the 2018 iPhone XS family and iPhone XR.

Low light photography

In the past, manufacturers of mobile phone cameras had to compromise between the amount of detail they could capture in good light and the brightness of images in low light. With pixel binning, both have been accomplished with the same image sensor.

Multimedia Messaging Service

Camera phones can share pictures almost instantly and automatically via a sharing infrastructure integrated with the carrier network. Early developers, including Philippe Kahn, envisioned a technology that would enable service providers to "collect a fee every time anyone snaps a photo". The resulting technologies, Multimedia Messaging Service and Sha-Mail, were developed in parallel to and in competition with open Internet-based mobile communication provided by GPRS and later 3G networks.
The first commercial camera phone, complete with infrastructure, was the J-SH04, made by Sharp Corporation; it had an integrated CCD sensor, with the Sha-Mail infrastructure developed in collaboration with Kahn's LightSurf venture, and marketed from 2001 by J-Phone in Japan today owned by Softbank. It was also the world's first cellular mobile camera phone. The first commercial deployment in North America of camera phones was in 2004. The Sprint wireless carriers deployed over one million camera phones manufactured by Sanyo and launched by the PictureMail infrastructure developed and managed by LightSurf.
While early 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 website. Connecting cables or removable media that would enable the local transfer of pictures were also usually missing. Modern smartphones have almost unlimited connectivity and transfer options with photograph attachment features.

External camera

During 2003, 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.
One of these examples was the Nokia Fun Camera announced together with the Nokia 3100 in June 2003. The idea was for it to be used on devices without a built-in camera and be able to transfer images taken on the camera directly to the phone to be stored or sent via MMS.
In 2013–2014, Sony and other manufacturers announced add-on camera modules for smartphones called lens-style cameras. They have larger sensors and lenses than those in a camera phone but lack a viewfinder, display, and most controls. They can be mounted to an Android or iOS phone or tablet and use its display and controls. Lens-style cameras include:
  • Sony SmartShot QX series, announced and released in mid-2013. They include the DSC-QX100/B, the large Sony ILCE-QX1, and the small Sony DSC-QX30.
  • Kodak PixPro smart lens camera series, announced in 2014.
  • The DxO ONE is a small camera that attaches to an Apple iPhone or iPad using the Lightning connector port.
  • Vivicam smart lens camera series from Vivitar/Sakar, announced in 2014.
  • HTC RE HTC also announced an external camera module for smartphones, which can capture 16 MP still shots and Full HD videos. The RE Module is also waterproof and dustproof, so it can be used in a variety of conditions.
External cameras for thermal imaging also became available in late 2014.
Microscope attachments were available from several manufacturers in 2019, as were adapters for connecting an astronomical telescope.