Some systems work jointly with a computer, offering the option of sharing the computer monitor. Many video magnifiers also provide other special on-screen features and controls including underlining or overlining of text. Controls for contrast and brightness are also standard. Some manufacturers of video magnifiers that use handheld cameras offer a writing stand as an accessory.Īll video magnifiers offer the option of viewing black letters on a white background or white letters on a black background. Handheld cameras are often on rollers, which make them easier to move across a flat working surface. They can magnify almost anything within reach, including labels on packages of food and medicine.
In contrast to stand-mounted cameras, handheld cameras are designed for bringing the camera to the material to be viewed. Stand-mounted cameras are particularly effective for handwriting because a hand can fit under the camera. To make the process of viewing easier, a table that is movable from the top of the page to the bottom and side to side (referred to as an x-y table) is used with most stand-mounted cameras. Most cameras also need their own light source.Ĭameras that are mounted on a fixed stand require the reading material to be placed under the camera and moved across and down the page. Lower cost video magnifiers often use cameras that have a fixed focus and cannot vary magnification or camera-to-target distance. In most of these systems, magnification level and focus are set after choosing a comfortable and functional working distance between the camera and the material to be viewed. Cameras with zoom lenses provide variable magnification. A video magnifier, or closed-circuit television (CCTV) system, uses a stand-mounted or handheld video camera to project a magnified image onto a video monitor, a television (TV) screen, or a computer monitor.
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