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Abstract | Market Needs | State-of-the-Practice | Issues to Consider | References AbstractConsumers, researchers, and manufacturers have identified improved access to consumer electronics as a high priority need for persons with visual impairments. The characteristics and capabilities of these technologies are a critical determinant of a person's ability to function independently within their own home and community. Currently, there are a number of devices and techniques used to provide access to electronic products, ranging from low-tech products (tactile labels) to much more advanced, high tech devices (smart appliances). Universal access to consumer electronics has not been achieved and there are numerous technical challenges to overcome. Advancements to technologies in this area represent significant business opportunities and will enhance the quality of life for numerous populations. [ Top of Page ] Market NeedsConsumer electronics include an ever-growing number of products that Americans use on a daily basis. Within the home, this category represents products ranging from alarm clocks to washing machines, including small and large appliances, thermostats, DVD players, cell phones, stereo equipment and television sets. In the community, this category includes such devices as ATMs, voting machines, vending machines, debit card terminals, cash registers, and public phones. As advancements in electronic technology make their way into more and more aspects of daily life, new complications arise for persons with visual impairments. Increasingly, electronic devices provide a digital display as output for each step in a programming sequence, but offer no auditory cues as to where one is within that sequence. People who do not have full use of their vision may have difficulty operating these devices or may be completely unable to operate them. In addition, complex dynamic digital input/output menu driven interfaces are becoming more and more commonplace. These interfaces present an even greater barrier to universal access. Where tactile labels may be sufficient for a static touchpad, they will provide little assistance with a dynamic touch-screen, or in products that require input in a particular sequence. In many instances a lack of auditory, tactile, or enhanced visual information makes operation of these devices a daunting task. People with visual impairments employ the use of a number of products and methods to interact with consumer electronics. For the 7.7 million people who have difficulty seeing the words and letters in ordinary newsprint, but have retained some usable vision, many suitable methods of object identification and operation have been devised (McNeil, 2001). For example, raised input buttons, large print, high contrast lettering and displays, enhanced lighting, and magnifiers can eliminate much of the strain experienced by an individual who has residual vision. Those persons with a total lack of usable vision, such as the 1.8 million Americans who are totally unable to see the words and letters in ordinary newsprint, and/or those people who have little to no light perception have very different needs from those who do have some residual vision (McNeil, 2001). Generally, the population without usable vision must rely on auditory and tactile cues or another sighted person to perform many tasks of daily living. While some technologies do exist to enable people with visual impairments to access consumer electronics, there is an opportunity for significant improvement in these areas. Enhancements to current technology could provide improvements to consumer electronics that are difficult, if not impossible for persons with visual impairments to access. Advances to technologies such as smart homes and wireless networks show great promise in providing universal access for consumer electronics not only in the home environment, but in community, educational, and vocational settings as well. [ Top of Page ] State-of-the-PracticeDevices used to access and control consumer electronics encompass a wide range of technologies. Products currently available on the market include labeling systems, magnifiers, enhanced lighting, auditory feedback, and tactile feedback, all of which can be incorporated to assist users in finding and activating controls on devices. Also, auditory tones and/or speech output may be available on some products to give the user the information that is otherwise provided in display areas. For the purposes of this project consumer electronics and the assistive technology devices utilized by persons with visual impairments to access these products, have been divided into three levels: "simple" (blender or tape cassette player), "intermediate" (microwave or oven), and "complex" (remote control). SimpleThe simple category refers to products where the information provided by any one button and the meaning of that information is static. [Examples include operating a blender or a standard telephone, where buttons may be sequentially pressed, however the input sequence will not affect the meaning of the information conveyed by each button, and the response triggered by pressing that button will not change.] (A "2" is a "2", regardless of when the button is pressed.) Adequate lighting, magnifiers and labeling can be helpful when operating these devices; however there is a need for further advancement in this category. Adequate lighting is important for performing near distance tasks. The type of lighting and its intensity, color and direction can strongly impact visual functioning. Too much or too little light can be a problem for a person with low vision and each person will need to evaluate the light that works best for him or her. Many types and styles of task lighting are available with multiple options. These options include floor or tabletop models with swing or flexible arm, and with or without magnifying lenses of varying strengths. The most useful lighting for people with impaired sight is full spectrum, followed by incandescent lighting, halogen lighting, and fluorescent lighting (Center for the Partially Sighted, 2001). Hand-held magnifiers are hand-held devices that can be placed over an object or text to enlarge or magnify it. These magnifiers are generally very easy to manipulate which enables users to adjust the working distance easily (Levack, 1994). The portability of these magnifiers makes them an attractive option for many people with visual impairments. A stand magnifier, which sits on a base or has a clamp with an adjustable or flexible arm is also common. Stand magnifiers are an option when both hands are needed to perform the task or when motor control is not optimal. Magnifiers come in illuminated and non-illuminated versions. They should work to enlarge the textual information on all sizes of documents, from business cards to posters. Digital video magnifiers use a video camera to project a magnified image onto a video monitor, computer monitor or TV screen. They are used to enlarge written materials and small objects, enabling a person with low vision to read and write. Digital video magnifiers should be portable, should include options for speech output and should employ high-resolution, auto-focus cameras and flat-screen technology. Video magnifiers should be able to scale text while maintaining clarity, contrast and resolution of the image. Labeling systems may feature large print, high contrast numbers or letters, Braille writing or other raised characters. Many consumer electronics are originally manufactured with large print controls, such as telephones and calculators. Products that do not offer this feature can be adapted by way of self-adhesive labels designed for aftermarket application. High Contrast Labels allow the user to place highly visible tags on household items. The labels are available in many high contrast colors as each individual's optimal viewing preference will be different depending upon the type and level of visual impairment. Color contrast has been studied extensively and guidelines developed for the three most important perceptual dimensions of color, which are hue, lightness, and saturation (Lighthouse International, 2003.) High Contrast Displays allow the user to create customized color combinations, levels of screen brightness and levels of contrast displayed. The user may often select various text and background colors independently to create the display that best suits their visual ability. IntermediateThe intermediate category represents devices where the information provided by any one button stays the same (A "2" is always a "2"), but the input sequence will change the meaning of the information conveyed by each button. (A "2" is a "2", but it may represent "2 minutes" or "level 2 heat control" depending where in the input sequence the button is pressed.) For example, microwaves and stoves that require input for temperature, time, and cooking settings typically require the user to input information by way of a static touchpad, and provide feedback to the user through a dynamic display screen. These dynamic displays often use menu-based systems in order to input a series of commands to perform one or more functions. Menus are a complex representation of information which require an equally complex sequence of input actions to control a product. Many of the labeling and magnification devices described in the simple category can also be used to access intermediate devices. However, static labels cannot represent dynamic output and magnifiers will not support persons who have no residual vision. Access is also accomplished through more advanced technology such as auditory feedback and speech output. Auditory feedback provides the user with a non-visual cue that an operation has been performed. For example, the user may hear a beep each time a button is pressed, with a longer tone at the end of a sequence. Auditory feedback has been incorporated into some devices, such as home security systems, thermostats, microwaves, DVD players and insulin pumps. Audio tones may provide enough feedback for independent use of some devices. However other products require speech output to access dynamic displayed messages. Speech output verbalizes information that would otherwise be accessed by way of viewing a display screen. Products that have integrated this feature into their design include talking calculators, talking medical instrumentation, talking cooking equipment (scales and measuring cups), some cell phones, and some appliances, such as high-end microwaves. This is an area that offers great promise but there is still a great deal of room for advancement. ComplexThe complex category of consumer electronics consists of the user, an input device, and one or more devices controlled by the input device. Input devices may use dynamic or sophisticated static input and output interfaces. Some examples include: a universal remote control for a VCR, DVD player, and television, an Automatic Teller Machine (ATM) interacting with one or more remote financial institutions, and an environmental control unit for heating, air conditioning, ventilation, and humidity control systems. Speech input, wireless and smart technologies may assist individuals in accessing and operating these types of interfaces. However they have not been incorporated into the majority of consumer electronics, and generally, are not yet widely available. Speech input allows the user to control a device by way of voice activation. These products may or may not also include voice output. Currently, there are devices on the market available to control lights, remote controls, and some other home functions by way of speech input. Smart Homes are homes that incorporate networked connections to enable a user to remotely control certain functions within their homes. Devices that are part of a smart home can be termed"smart appliances." Network connections may be established by way of cable, infrared or radio links. The type of network connection required depends on factors such as the desired speed of data transmission, building design plans and cost of implementation (European Commission, 1996). The control interface for a (wire based or wireless) network could interface with home appliances (microwaves, ovens, and refrigerators), environmental control units (heating, cooling), privacy and access devices (door locks, window blinds, door openers), and communication products (wireless phones). This interface will allow users to get information about the home's condition and remotely control home systems and appliances as well as gain access to information and entertainment resources from inside and outside the home. Various standards are being developed to support a networked home environment. Wire-based networks occur in a fixed or static environment. Wire-based networks may be linked by Ethernet cables, phone cords, power lines or other dedicated linkage. Participants in the network and their location are generally considered to be constant, as they are hard-wired into a particular site. Wireless networks send signals through space rather than through a cable or wire. They generally are used for communications that send and receive data through a transmission and reception device attached directly to the network. Communication may be accomplished through two general types of transmission: radio frequency or infrared. Radio frequency refers to any wireless technique that uses radio frequencies to transmit information. Examples include wireless Ethernets such as Home RF and Wi-Fi (wireless fidelity), and personal area networks such as Bluetooth. Infrared communications include two types which are directed IR and diffused IR. Directed IR requires unobstructed line-of-sight connection. Diffused IR floods a specific area with a strong infrared signal by reflecting off other sources, thereby eliminating the need for line-of-sight. [ Top of Page ] Issues to Consider
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