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A camera phone is a mobile phone which is able to capture photographs. Most camera phones also record video. The first camera phone was sold in 2000 in Japan, a J-Phone model. Most camera phones are simpler than separate digital cameras. Their usual fixed-focus lenses and smaller sensors limit their performance in poor lighting. Lacking a physical shutter, some have a long shutter lag. Photoflash is typically provided by an LED source which illuminates less intensely over a much longer exposure time than a bright and near-instantaneous flash strobe. Optical zoom〔(【引用サイトリンク】title=Take High-Quality Pics With Your Phone's Low-Quality Camera )〕 and tripod screws are rare and none has a hot shoe for attaching an external flash. Some also lack a USB connection or a removable memory card. Most have Bluetooth and WiFi, 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 (a few are up to 1"), their capabilities approach those of low-end point-and-shoot 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. Most model lines improve their cameras every year or two. Some smartphones only have a menu choice to start a camera application program and an on-screen button to activate the shutter.〔(【引用サイトリンク】title=Motorola DROID X vs. HTC Droid Incredible )〕 Others also have a separate camera button, for quickness and convenience. A few 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. 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. 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. However, the touch screen, being a general purpose control, lacks the agility of a separate camera's dedicated buttons and dial(s). == Technology == Some camera phones use CMOS image sensors, due to largely reduced power consumption compared to CCD type cameras, which are also used, but not in today's camera phones. Some of today's camera phones even use more expensive Back Side Illuminated CMOS which use energy lesser than CMOS, although more expensive than CMOS and CCD. Images are usually saved in the JPEG file format, except for some high-end camera phones which have also RAW feature and the Android (operating system) 5.0 Lollipop has facility of it. The wireless infrastructure manages the sharing. The lower power consumption prevents the camera from quickly depleting the phone's battery. In any case, an external battery or flash can be employed, to improve performance. As camera phone technology has progressed over the years, the 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. The latest generation of phone cameras also apply distortion (optics), vignetting, and various optical aberration corrections to the image before it is compressed into a .jpeg format.' Most camera phones have a digital zoom feature. A few have optical zoom. An #External camera can be added, coupled wirelessly to the phone by Wi-Fi. They are compatible with most smartphones. Android Lollipop 5.0 allows apps to take RAW format pictures.〔(【引用サイトリンク】title=Android 5.0 Camera Tests Show Update Instantly Improves Every Smartphone )〕〔(【引用サイトリンク】title=Panasonic announces Lumix DMC-CM1 smartphone with 1-inch sensor )〕 Windows Phones can be configured to operate as a camera even if the phone is asleep. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Camera phone」の詳細全文を読む スポンサード リンク
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