A flat cable looking like two cables glued together commonly used for audio applications.

A lens with a variable focal length providing the ability to adjust the size of a projected image without moving the projector or provide a range of projector placements that can produce the same size image. See Zoom Ratio.

Is the ratio between the smallest and largest image a lens can projector from a fixed distance. For example, a 1.4:1 zoom lens ratio means that a 10 foot image without zoom would be a 14 foot image with full zoom. Conversely, a 10 foot diagonal image at 15 feet with no zoom would still be a 10 image at 21 feet at maximum zoom (15 x 1.4 = 21 feet). A zoom lens is "not as bright" as a fixed lens, and the higher the ratio, the less light output.