Assistive Technology: Vision Products

Original Editor - Robin Tacchetti Top Contributors - Robin Tacchetti, Naomi O'Reilly and Kim Jackson

Introduction[edit | edit source]

Millions of people globally have vision loss or a visual impairment. Recent estimates that there are over 43 million blind people and 295 million people suffering from moderate-to-severe visual impairment with the majority of these individuals living in middle and low-income countries.[1] Visual impairment can be classified by one's visual acuity:

  • Blind: Vision Below 20/400
  • Low Vision: Corrected vision is less than 20/70 and greater than or equal to 20/400[2]


Visual impairment impacts quality of life in various ways such functional daily activities, indoor and outdoor movement, employment and independence. [3] Additionally, dangerous situations can occur when these individuals encounter environments unfamiliar to them.[4] These barriers individuals face daily can be overcome with the help of assistive technology.[1] The wide range of vision assistive technology can be a simple low-tech device (large print book) to an expensive high-tech solution such as a Refreshable Braille Display.[5] Recent advances in technology have expanded the digital assistive technology space.[1][4]

Global Cooperation on Assistive Technology (GATE)[edit | edit source]

In 2014, the World Health Organization introduced the Global Cooperation on Assistive Technology (GATE). This initiative's addresses the significant gap in all countries between supply and demand for assistive technology. GATE published a list of the top 50 priority assistive products based on widespread need amongst the disabled population. Of those 50 priority products, 16 are geared towards people with visual impairments. These vision assistive products help by the use of sound, smell, or sense of touch or vibration.[5]

Different Types of AT[edit | edit source]

  1. Optical:
    • prescribed by ophthalmologists
    • consist of one or more lenses to adjust/increase visual image
    • devices can include: eyeglasses, telescopes, contact lenses, magnifying glasses
  2. Non-optical
    • improve vision without use of lenses
    • simple, transform environment and materials
    • devices include: enlarged text, lighting, felt tip pens, contrasting colors, didactic books
  3. Electronic
    magnifying glass
    • provide access to printed material that optical magnifying glasses are not able to expand enough for reading
    • able to magnify up to 66 times without distortion
    • devices include: scanners, autonomous text readers, video magnifiers, electronic magnifying glass
  4. Information and Communication Technology (ICT)
    • works through a combination of sound, tactile and visual interfaces
    • devices include: computer, screen magnifier software, screen readers[2]

Assistive Visual Technology by Tasks[edit | edit source]

Reading[edit | edit source]

Many activities in our daily lives requires the act of reading. These assistive devices below can help individuals with visual impairment:

  1. large print books
  2. reading stands
  3. low vision lamps
  4. optimal magnifiers
  5. electronic magnification aids
  6. digital audio recorders
  7. screen readers
  8. braille reading systems[5]
braille alphabet

Math[edit | edit source]

It can be very challenging for children with visual impairment to learn math concepts. It can be very difficult to interpret shapes, direction and quantification without visual input. The following devices can help support them:

  1. Braille Systems
  2. tactile Geometric kit
  3. Talking Calculator[5]
Talking Calculator

Writing[edit | edit source]

Typical or visual writing can be particularly challenging for individuals with visual impairment. The following devices can assist them:

  1. Large Computer Keyboards
  2. Audio Digital Recorder
  3. Braille Writing System[5]
    Braille Writing System

Orientation and Mobility[edit | edit source]

Walking is a necessary element of daily life. Below is a list of a variety of canes that can assist individuals with visual impairment.

  1. Walking: identifies objects in the path of the user
  2. Identification: notifies general public that the user has a visual impairment
  3. Guide: identifies curbs and steps for users with some residual visual function
  4. Support: provides physical support for the user
  5. Green: indicates user has low vision
  6. White: indicates user is blind
  7. Red and White: user has both visual and hearing impairment[5]
    Walking Cane

Activities of Daily Living (ADL)[edit | edit source]

Assistive technology can help individuals perform ADLs to allow more independence in their daily routine. Below are some devices that can be incorporated into a visually impaired person's life:

  1. Talking watch
  2. Liquid level sensor: alerts the user about the level of liquid in a cup via sound or vibration
  3. Simplified mobile phone: easier to navigate
  4. Money identifier: identifies money with a voice function
  5. Color identifier: differentiates a variety of colors
  6. Pill organizer[5]
pill organizer

Smart Phones[edit | edit source]

Technological advances in smartphones have facilitated persons with visual impairments the ability to access information that increases their independence, participation and quality of life. Smart phone features that users can access include:

  1. TalkBack: the device verbally speaks words upon the users touch; will read aloud what is under the user's finger
  2. Voice Over: provides voice feedback in relation to what is on the screen; user can slide around on screen until they touch what they are looking for
  3. Zoom Magnification: magnifies the entire screen.[3]

Resources[edit | edit source]

References [edit | edit source]

  1. 1.0 1.1 1.2 Senjam SS. Smartphones for Vision Rehabilitation: Accessible Features and Apps, Opportunity, Challenges, and Usability Evaluation. InSoftware Usability 2021 May 7. IntechOpen.
  2. 2.0 2.1 BORGES WF, MENDES EG. Usability of assistive technology applications by people with low vision. Revista Brasileira de Educação Especial. 2018 Oct;24:483-500.
  3. 3.0 3.1 Senjam SS, Manna S, Bascaran C. Smartphones-Based Assistive Technology: Accessibility Features and Apps for People with Visual Impairment, and its Usage, Challenges, and Usability Testing. Clinical optometry. 2021;13:311.
  4. 4.0 4.1 Hwang J, Kim KH, Hwang JG, Jun S, Yu J, Lee C. Technological opportunity analysis: Assistive technology for blind and visually impaired people. Sustainability. 2020 Oct 20;12(20):8689.
  5. 5.0 5.1 5.2 5.3 5.4 5.5 5.6 Senjam S. Assistive Technology for People with Visual Loss. Delhi Journal of Ophthalmology. 2019 Oct;30(2).