With determination and will power, everything is possible! And Pranjal Patil definitely proves that. She is India's first visually impaired woman IAS officer. Pranjal hails from Ulhas Nagar in Maharashtra who lost her vision at the age of six.

Source: Pranjal Patil, India's First Blind IAS Officer, Takes Charge as Sub-Collector in Kerala, 2019

Blindness & Low Vision

Blindness & Low Vision

The Blindness and Low Vision Section of the DEEPAK: NDLI Disability Knowledge Portal presents extensive information on all aspects of the life of persons with blindness or visual impairment. This is divided into eight subsections (detailed below). The focus has been kept on Education, Employment, and Training through first three subsections. Caregiving including support services and Institutions dealing with blindness are covered next. Assistive Technology and Android & iOS Apps have become critical assistance in all the activities. These are covered in the following two subsections. Last but not the least, the story of few Achievers, who have excelled in spite of all odds of disability and attitude of the society at large are chronicled as a documentation for achievements of human will.

While the portal is primarily designed for persons with blindness or visual impairment in India, it does cover a lot of information in respect of science, technology, history, and practices that are agnostic to geographic and political boundary.

Prevalence of blindness and visual impairment in population aged ≥50 years in India

Nationwide Representative Blindness Survey was conducted among people aged ≥ 50 years in 31 districts of 24 States/Union territories of India from 2015-19. Out of 93,018 enumerated individuals 85,135 persons were examined. Prevalence was as follows:

  • Blindness: 1.99%

  • Severe Visual Impairment (SVI): 1.96%

  • Moderate Visual Impairment (MVI): 9.81%

  • Early Visual Impairment (EVI): 12.92%

  • Moderate Severe Visual Impairment (MSVI): 11.77%

  • Visual Impairment (VI): 13.76%

  • Functional Low Vision (FLV): 1.03%

  • Pinhole blindness: 1.75%

  • Globally, at least 2.2 billion people have a near or distance vision impairment. In at least 1 billion – or almost half – of these cases, vision impairment could have been prevented or has yet to be addressed.

  • This 1 billion people includes those with moderate or severe distance vision impairment or blindness due to

  • Cataract (94 million)

  • Unaddressed Refractive Error (88.4 million)

  • Glaucoma (7.7 million)

  • Corneal Opacities (4.2 million)

  • Diabetic Retinopathy (3.9 million), and

  • Trachoma (2 million)

as well as near vision impairment caused by

  • Unaddressed Presbyopia (826 million)

  • In terms of regional differences, the prevalence of distance vision impairment in low- and middle-income regions is estimated to be four times higher than in high-income regions.

  • With regards to near vision, rates of unaddressed near vision impairment are estimated to be greater than 80% in western, eastern and central sub-Saharan Africa, while comparative rates in high-income regions of North America, Australasia, Western Europe, and of Asia-Pacific are reported to be lower than 10%.

  • Population growth and ageing are expected to increase the risk that more people acquire vision impairment.

  • The majority of people with vision impairment and blindness are over the age of 50 years; however, vision loss can affect people of all ages.

  • Vision impairment poses an enormous global financial burden with the annual global costs of productivity losses associated with vision impairment from uncorrected myopia and presbyopia alone estimated to be US$ 244 billion and US$ 25.4 billion.

  • Most people with visual impairment are older, and females are more at risk at every age, in every part of the world.

  • About 87% of the world's visually impaired live in developing countries.

  • About 85% of all visual impairment is avoidable globally.


Further Reading:

About Blindness and Visual Impairment

We address few common questions in the sections below:

  • Blindness and Visual Impairment: Is blindness and visual impairment different? What are grading of visual impairment in the world and in India?

  • Nature and Prevalence of Vision Loss: What are the primary causes for vision loss? How prevalent are they? Across the world and in India.

  • Vision with Visual Impairment: What does a person with VI sees?

  • Common Eye Tests: What are the common tests for eyes? Which test is done for what purpose?

  • Deafblindness: Being deafblind doesn't necessarily mean that you are totally deaf or totally blind – most individuals who are deafblind have some residual sight and/or hearing. It is a unique disability in its own right

  • Seeing through the Eyes of the Blind: How do blind and visually impaired people look at life, at themselves, at the sighted and so on? How do they cope with life?

  • Acronyms and Glossary of Terms

Just because a man lacks the use of his eyes doesn't mean he lacks visionStevie Wonder

About the NDLI Portal on Blindness & Low Vision

Globally, 1.1 billion (14.33% of population) people were living with vision loss in 2020:

  • 43 million people are blind (crude prevalence: 0.5%).

  • 295 million have moderate to severe vision impairment (crude prevalence: 3.7%).

  • 258 million have mild vision impairment (crude prevalence: 3.3%).

  • 510 million have near vision impairment (crude prevalence: 6.5%)

Of that, 275 million (19.38% of population) are in India, the highest for any country:

  • 9.2 million people are blind (crude prevalence: 0.65%).

  • 79.0 million have moderate to severe vision impairment (crude prevalence: 5.56%).

  • 49.1 million have mild vision impairment (crude prevalence: 3.45%).

  • 137.7 million have near vision impairment (crude prevalence: 9.68%)

* Crude prevalence is computed with population as a whole - no subdivision or refinement

* Population of the world is taken as 7.674 billion

* Population of India is taken as 1.422 billion

About 25% or one in every four blind or visually impaired person is in India!

This means a huge challenge for India to support these people to lead respectable independent life, be employed with equal opportunity, have access to education, and access to all kinds of information. As a part of National Digital Library of India, this portal attempts to provide access to free information for all people with blindness or low vision and those who are related to them in some way or other.

The portal is organized as follows:

  • Resources: Links to various digital resources for education (like audiobooks), research (like Visual Atlas), and information are collated here.

  • Employment: Contrary to the commonly held belief that the blind and visually impaired cannot perform at par with their sighted counterparts at the workplace, we list a galore of opportunity for equal opportunity employment and talk about organizations who actively support and facilitate them.

  • Training & Vocational: Training and vocational practices are critical for the blind and visually impaired to lead independent life and seek equal opportunity employment. This section provides information on several organizations and programs in this regard.

  • Caregivers: As it is said - Be empathetic, not sympathetic. Everyone needs empathetic caregivers - parents, family, teachers, support groups, volunteers - for rightful development to reach one's potential. So does the the blind and visually impaired, albeit, often in a different way. In this section we collate information on guidelines & policies, awareness & advocacy initiatives, availability of support groups & services, vision & Braille centers, educative videos, and manufacturers & distributors for the ease of functioning of the caregivers. The information is organized along the following sections:

    • Guidelines & Policies: Various national and international guidelines and policies may help the caregivers

    • Awareness & Advocacy: Awareness about the life of a person with blindness or low vision is critical for the sighted people, caregivers and policy makers. And advocacy is regularly needed for establishing proper legal order and policies.

    • Support Groups: At national and international levels, various support groups help the people with blindness to lead an independent life.

    • Support Services: Various support services in India, including Low Vision Advisory, Orientation & Mobility, and Talking Book Services, are detailed.

    • Vision Centers: Various vision centers in India provide free, subsidized or paid quality services for the visually impaired

    • Braille Production: Producing braille text books and documents at a large scale is a critical need for India having a large number of people with blindness or low vision. Several production centers have been meeting these needs.

    • Teachers of Visually Impaired (TVI): Training, teaching or mentoring the visually impaired is an non-trivial task. Several resources and options for formal / informal training are discussed.

    • Dealers: Quality and inexpensive manufacturers and distributors of assistive technology and other solutions for persons with visual impairment in India are critical for caregivers.

  • Institutions: The Government, its Ministries and various Departments, Institutions, Non-Government Organizations (NGO) etc. are working to support the lives, education, training, employment and livelihood of people with blindness and visual impairment.

    • International Organizations: Institutions - Government as well as private - across the world, primarily in USA and Europe, that work for the blind that can be of assistance to the people with blindness and visual impairment in India.

    • National Institutions & Composite Regional Centers in India: Activities of Institutions of the GoI and the regional centers in different states.

    • NGOs in India: Activities of the NGOs across India and a few International NGOs with centers and / or linkages in India.

    • Special Schools in India: Public and Private Special Schools for the students with blindness and visual impairment across various states of India.

  • Assistive Technology: People with Blindness or Low Vision are challenged in one - the vision - sense. Appropriate use of technology can make up for this gap in one or more of the following ways:

    • Visual Enhancement: The existing visual acuity can be improved with the use of glasses, magnifiers etc.

    • Visual Substitution: It can help one see with one or more non-visual senses. Like a text can be Braille coded (reading by touch), it can be read out loud (reading by hearing), a map or geometric drawing can be tactile with raised lines (reading diagrams by touch), nearness of obstacles could be sensed by pressures on the tongue (sensing by haptic), and so on.

    • Visual Replacement: Replacement could work in a wide range from eye donation (retina replacement) to optical prostheses and so on. The core idea is to replace or bypass the existing vision system with alternate with AT.

We review AT for Vision in the aspects of reading and writing Braille / textual information, graphical or diagrammatic information, generic aids to vision improvement, navigation (orienting oneself and be mobile), support in education, games and leisure activities and day-to-day life through the following sections:

    • Read & Write Braille: We take a look at Braille System and its readers and writers. We also present Braille printing options.

    • Read & Write Text: We look at various screen reading options for normal display text, OCRs, Digital Pens, Notetakers, Large Print, and importantly the accessibility formats and accessibility needs of the webpages.

    • Read & Write Images: While Braille and Screen reading mostly addresses the issues of text-based communication, images remain a challenge for the blind and the visually impaired. Though raised line methods were used in the world's first complete atlas for the blind published in the United States in 1837, it has taken several decades for it to be a large scale affordable technology. We look at the options today for maps, geometric figures etc. and also the exploratory use of tactile graphics for arts.

    • Low Vision Aids: Glasses have been used for correcting refractive errors of the eye (short and long sights) from time immemorial. Over time better lens material have been introduced along with a range of smart glasses that do lot more than just magnification.

    • Orientation & Mobility: Moving in a 3D space requires orientation and navigation capabilities. Dogs and Cane have traditionally been the friend of a blind for this. With AT, several Electronic Travel Aids (ETAs), Electronic Orientation Aids (EOAs) and Mixed EO&TAs have been introduced. They can be external to the user and / or can be carried by the user (for example, infrared light transmitters and handheld receivers). We explore various option for outdoor as well as indoor navigation, and a range of new innovations being worked on.

    • Education: Education is a key need for every person. So for the blind and visually impaired though there are more obstacles for a challenged student to be at par with her sighted counterpart. We discuss ATs for Reading, Writing, Mathematics, Science and Social Studies, Computer Access, O & M, and even Art, Music and Physical Education. We also refer to supportive pedagogy, processes and tools in this regard.

    • Games & Leisure:

    • Day-to-day Life:

In every section of AT we start with the general information on the issues and approach of AT, history of development and challenges, then present the available ATs and solutions, and finally conclude with the innovations, research, and future of the respective ATs.

  • Android & iOS Apps: Apps have changed the way we live today and they have been a great boon for the people with blindness and visual impairment to enhance their accessibility in various spheres of activities and ease of functioning and degree of independence in life. While both Android and iOS phones have support for a range of accessibility, a plethora of apps help the user in the various areas including, but not limited to, the following:

    • Scanner, Reader, and Writer Apps

    • Magnifier Apps

    • Navigation, Mobility and Orientation Apps

    • Office and School Apps

    • Job Apps

    • Lifestyle Apps

  • Achievers: Whether it is government service like IFS / IAS, it is music or drama, it is sports, it is service to people - the people with blindness and visual impairment have achieved a lot, reached heights, and inspired others.

The only thing worse than being blind is having sight but no visionHelen Keller

A Snellen chart is an eye chart that can be used to measure visual acuity. Snellen charts are named after the Dutch ophthalmologist Herman Snellen, who developed the chart in 1862.

A common Snellen chart is printed with eleven lines of block letters. In VA testing on Snellen chart, person normally sits at a distance of 6m from the chart on which letters of standard decreasing size are there in rows. Top line has a single letter which should be readable at a distance of 60m. Visual acuity is recorded as a ratio with numerator of 6 (distance at which patient sits) and the denominator of the smallest possible size being read by the patient. For example, a vision record of 6/60 means that patient sitting at 6m could read letter in top line only, which should normally be read at 60m. Instead of distances being in meters, it may also be measured in feet. 6m is about 20'. Therefore, a vision of 6/6 in meters, is equivalent to a vision of 20/20 in feet. Similarly, a vision of 6/60 in meters, is equal to 20/200 in feet.

Visual Acuity (VA)

Visual Acuity commonly refers to the clarity of vision, but technically rates an examinee's ability to recognize small details with precision. Visual acuity is dependent on optical and neural factors:

    • the sharpness of the retinal image within the eye

    • the health and functioning of the retina, and

    • the sensitivity of the interpretative faculty of the brain

It is a measurement determined by the letter chart tests we take when we get our eyes checked; the number represents your eyes’ clarity or sharpness. For example, a person with a visual acuity measurement of 20/70, who is 20' away from an eye chart sees what a person with 20/20 vision can see from 70' away.

A logMAR chart (Logarithm of the Minimum Angle of Resolution) is a chart consisting of rows of letters that is used by ophthalmologists, orthoptists, optometrists, and vision scientists to estimate visual acuity. The chart was developed at the National Vision Research Institute of Australia in 1976, and is designed to enable a more accurate estimate of acuity than do other charts like Snellen chart.

When using a LogMAR chart, visual acuity is scored with reference to the logarithm of the minimum angle of resolution. An observer who can resolve details as small as 1 minute of visual angle scores LogMAR 0, since the base-10 logarithm of 1 is 0; an observer who can resolve details as small as 2 minutes of visual angle (i.e., reduced acuity) scores LogMAR 0.3, since the base-10 logarithm of 2 is near-approximately 0.3; and so on.

Visual Acuity Testing is explained nicely in this YouTube video.

Blindness and Visual Impairment

Subjectively or qualitatively, lack of normal vision can be defined as:

  • Visual Impairment: A decrease in the ability to see to a certain degree that causes problems not fixable by usual means, such as glasses

  • Blindness: The state of being unable to see due to injury, disease or genetic condition

Objectively and quantitively, however, it is defined is relations to someone's Visual Acuity (VA is explained on left).

Different nations in the world follow different classification or grading for loss of vision. So we present definitions from WHO, US and India.

WHO Definition of Blindness

For International comparison, WHO has defined blindness at the level of 3/60 or inability to count fingers at a distance of 3 meters or 10 feet.

The International Classification of Diseases 11 (ICD-11, 2018) classifies vision impairment into two groups:

  • Distance vision impairment:

    • Mild – visual acuity worse than 6/12 to 6/18

    • Moderate – visual acuity worse than 6/18 to 6/60

    • Severe – visual acuity worse than 6/60 to 3/60

    • Blindness – visual acuity worse than 3/60

  • Near vision impairment: