CCTV: Closed-Circuit Television Systems

What is it and what does it do?
The closed circuit television (CCTV) or video magnifier is a system which uses a video camera to project a magnified image on a television screen or computer monitor. The camera consists of a zoom lens which magnifies an image onto the screen or monitor. In most cases, the zoom lens has a set magnification and focus which the individual user can manipulate and set when they have identified the most comfortable and functional working distance for the material. Some systems feature a lens that has an automatic focus, while others have a fixed focus which does not allow a varied magnification or camera-to-target distance.

The CCTV has two common styles. The first type of system is stand mounted where the material has to be placed onto a tray below the camera lens. This tray is also referred to as the “XY” table. This table/tray is able to be manipulated by the user to move left to right and up and down manually or with a switch. The stand mounted system is convenient to use to write because it is designed with enough space for a writing utensil to be used under the camera.

The second system is a handheld system or portable system. The camera is a separate unit which can be moved within its reaching distance to the object or material to be viewed. Some handheld systems are available with rollers which allows for the system to be moved smoothly on a flat surface. As with the stand mounted system, the some handheld systems offer a writing stand as an accessory item. These two systems can be found in one unit. A system can be both!


Who Benefits from its use?
Many low vision children and adults can benefit from the use of stronger magnification devices because glasses or hand held devices no longer give aid. It enables individuals with low vision to continue reading and different tasks their vision no longer allows them to complete, even with typical glasses or hand held magnification devices. The CCTV magnifies all printed text, making it readily accessible to individuals with low vision.

The CCTV creates opportunities for individuals to maintain their independence in selecting comfort level for reading. It allows for the individual to choose and create the best contrast, magnification, text and background color combinations, as well as whether or not they need white text on black or black text on white. These options help the individual create the best reading circumstances for themselves which helps them maintain their independence.

Individuals with the following conditions are potential users of the CCTV: macular degeneration, inoperable cataracts, retinitis pigmentosa, diabetic retinopathy, and glaucoma.

Product Features Included: (www.labor.state.ak.us)
The following items are basic features included:
- Camera with zoom (handheld or stand)
- Monitor/screen
- Magnification range of 2x to 60x+
- Reverse polarity
- Focus, magnification, contrast and hue controls
- XY table
- Varied monitor sizes

The following items are more advanced:
- B&W camera w/color monitor
- Color camera and monitor
- Foreground and background control
- Split image color or b/w presentation
- Line markers or windowing
- Selectable viewing window
- XY table motorized
- Computer compatibility

Distance Viewing Options:
- Auto focus
- Picture capture
- Invert image
- Color preferences
- Quick flip from distance to near viewing with auto focus
- External x/y tables
- Carrying bags

Portable Systems:
- Near magnification
- Magnification levels form 1-16x
- Writing mounts
- Invert colors
- Distance viewing options
- Reading by line, word, or paragraph (specific to My Reader)
- Capture text



Purchasing Considerations
The purchase of a CCTV is a big decision to make and should not be rushed into or taken lightly. The individual who will be using the CCTV should be the one testing each model and selecting any featured options they will need to best fit their use. The CCTV model options are large and vary in features. The following list should be considered in the purchasing of a CCTV system:
· Black and white or color camera
· Windowing options
· Adjustable monitor height
· Type of lighting used
· Camera type
· Split screen options
· Size and weight of system
· Inline (monitor positioned over video camera and XY table) or Out-of-line system (monitor is separate from video camera. Camera is next to monitor), or convertible inline/out of line (can be both)
(http://www.labor.state.ak.us)
· Magnification in adjustable increments
· Capable of reverse polarity
· Color screen or black and white
· Handheld or portable
· Compatibility with computers
· Manual or motorized reading table
(ATA, pg. 250)
· Screen size and resolution
· If it connects to a computer does it have a split screen option?
· If portable does it have its own power supply?
(http://snow.utoronto.ca/technology/products/cctv.htm)
· Use and rate of the CCTV(bills, medication labels, pleasure reading, etc)
· Ease of use and design
· Cost
· Funding availability/help resources

Conclusion
Closed circuit television (CCTV) is an excellent tool for an individual with low vision. The selection is enormous and is a highly personal choice for an individual to make. However, the benefits of being able to see items without the use of a handheld magnifier allows for the individual to continue on in a normal fashion hands free. The CCTV allows for the individual to remain independent in reading and writing.

However, nothing comes easy and the use of the CCTV will require training and practice as with any low vision device. Learning to move the XY table easily and being able to write using the screen will take some getting used to, but the benefits of hard work make it all worthwhile in the end. There is nothing better than bringing the world of print in sight again.

Primary Original Authors Unknown, from PCO Advanced Assistive Technology: modified and updated by Andrea Bodnari