Discovery Science: Technology – Video Technology

Technology – Video Technology

Video technology provides the means to record, store, process, and view sequences of images. Using computers, both professionals and amateurs can easily work with their video material.

A video camera takes a series of individual pictures in rapid succession which are converted into electronic signals, so that they can be stored electronically or processed using a computer. The recording can also be viewed immediately on a monitor. When the images are presented to the eye in rapid succession, they create the perception of movement. Video cameras with built-in storage are called camcorders.

A microphone is included, to record sound and high-end cameras allow users to attach specialized microphones depending on their needs. The sound signal can be monitored during the recording process using earphones. The most important part of a video camera is the photo-sensor. Many newer models have separate sensors for each of the three primary colors: red, green, and blue. Electronic optic stabilizers are also used, to prevent blurring.

Storage and processing

Modern camcorders store images digitally. Magnetic cassette tape has long been used for this purpose; how- ever, modern camcorders now store recordings on built-in hard drives or less spacious recordable DVDs and memory cards. Camcorders using memory cards for storage can be very compact in size.

In order to process a recording, it must be transferred onto a computer’s hard drive, where editing software can be used to rearrange scenes, create transitions, and add special effects, titles, and sound.

Video screens

Video material is generally viewed on screens, such as televisions or computer monitors. On the screen, each individual picture is made up of tiny pixels. For color screens, each pixel includes three illuminated dots in the primary colors red, green, and blue. The brightness of the dots varies to produce a particular color that is perceived by the eye. In traditional television screens, a stream of electrons stimulates individual pixels to produce light.

They do, however, require a large vacuum-containing cathode tube, so they are increasingly being replaced by the more efficient plasma and TFT (thin-film transistor) flat-screens.


primary colors: red, green, and blue. Electronic optic stabilizers are also used, to prevent blurring. Each pixel in a plasma screen has three tiny chambers. These contain a low-pressure mixture of the noble gases neon and xenon.

Each chamber can be electronically “ignited,” causing the gas to emit ultraviolet radiation. The radiation then strikes a light emitting substance. Depending on the chamber, the substance shines red, green, or blue.


TO PRODUCE COLOR effects, pixels within a screen use the “additive method,” based on the primary colors red, green, and blue The combination of red and green light produces yellow.

Green and blue together make cyan, while red and blue produce magenta. Combining all three of the primary colors produces white light.