A digital pen camera is a small portable electronic device that contains a camera to capture still or video images, memory to store those images, and some sort of a control system. These devices may or may not actually resemble pens. Some models, particularly those designed to resemble pens, are meant to be used covertly. Other types of digital pen camera are not intended for stealthiness but are designed to be easy to use, very lightweight, and portable. Some other sorts of pen camera are designed for specific tasks and are called pen cameras simply because of their size and shape.
Tiny spy cameras have a long and storied history. The US Central Intelligence Agency (CIA) and the Soviet KGB both used several models of miniaturized film camera in efforts to capture photos of sensitive information. Thanks to advances in technology, even a very simple mass-market digital pen camera compares favorably with those tiny marvels of Cold War technology.
The quality of the camera mounted in one of these small devices is crucial. Higher-quality digital cameras produce better images, and while more expensive, are not typically much larger than lower-quality cameras. A cheaper digital pen camera will certainly cost less money but may produce images that are too grainy or out-of-focus to be of use. Better-quality models capture clearer images.
Many of these cameras are able to record sound and video as well. Higher-quality and more expensive models will typically outperform their cheaper rivals. The quality of a built-in microphone is also important in determining overall performance. The amount of memory available, either as part of the pen camera system itself or through a slot for a memory card, determines how much video, how many images, and how much sound can be recorded.
Stealthy versions of the digital pen camera typically resemble the nicer sorts of ballpoint pen. The relatively wide body of such pens allows room for the needed lenses, microphones, and electronics. The actual pen portion of these devices is typically able to write but may not contain enough ink to do so for very long.
Less-stealthy versions are not disguised as actual pens. They are still very small and portable and fit comfortably in a typical pocket. They can be useful for recording interviews or conversations, so long as high-quality images and sound are not needed.
The digital pen camera USB endoscopic microscope is an example of one other type of digital pen camera. This device, which is available for home use, is called a pen camera because it uses a pen-sized and pen-shaped probe to position a camera. This camera magnifies and transmits an image from the tip of the device that allows it to serve as a microscope.