Providing accessibility to scientific documents to visually impaired readers

text of mathematical equations

It is estimated that over 900 million people worldwide suffer from some kind of visual impairment and up to 20% of the population suffer from some form of reading disorder. Many suffering from either of these print impairments are often excluded from learning and studying scientific material from an early age.

Our research is significant in providing equal opportunities to learners in STEM subjects by transforming the common practices of STEM publishers and accessibility support workers, as well as directly influencing existing and developing web technology standards.

The work has led to the implementation of production-ready open source software technology for accessible rendering of mathematics via aural and tactile transcription of formulae. The technology is widely used in the context of STEM web documents and for the production of high quality alternative formats for mathematical teaching, research documents and e-books. Consequently it has become an important part of other open source software and is employed in a number of commercial products such as screen readers and assistive technology tools, leading to a wide distribution and therefore to a positive impact of our research for learners worldwide.

Key researchers

Dr Volker SorgeDr Volker Sorge

School of Computer Science

Senior Lecturer,
Reader in Scientific Document Analysis

View profile

Research impact

The work on mathematical formula analysis and transcription together with the implementation of the research in a freely available open source library has made significant impact on the availability and accessibility of online learning resource to visually impaired and print impaired learners. It helps widening the participation of these vulnerable groups in learning and research of subject areas that were previously only available to the few that access to the right resources.

Transcription of mathematical formulas into text as well as the provision of interaction mechanisms to explore complex formulas can be used in a number of areas to allow learners independent access to content that is difficult to engage with and understand without the help of a trained assistive technology specialist. Some of these areas are:

  • Enabling accessibility to Mathematical notation for visually impaired and dyslexic users in screen reading software via voicing and synchronised highlighting.
  • Inclusion as assistive technology support in interactive editing and learning environments.
  • Provision of alternative texts in online learning resources, publications and eBooks.

The Speech Rule Engine as a freely available online tool provides these possibilities and is consequently used in a number of commercial and open source systems:


  • ChromeVox (Google), the screen reader for Google's ChromeOS. Chromebooks are primarily used in high schools in the US and ChromeVox is the pre-installed screen reader. By extension SRE is the solution for mathematics accessibility on ChromeBooks.
  • Equatio (TextHelp), a Math Writing software aimed at students with dyslexia.
  • ETS is currently in the process of testing and introducing SRE for their test preparation frameworks.

Open Source: 

  • MathJax, a JavaScript library for TeX-like typesetting of Mathematics on the web. MathJax's free CDN service sees over 4.5 million unique daily visitors. MathJax is also the mathematics rendering solution for the majority of LMS.
  • MathLive, an online math editing environment.
  • Webworks, an online math problem solving library.
  • PreText: Open Source textbooks that are widely used in the US. SRE itself has an average of 4000 downloads a week on npm.

Underpinning research

Ensuring accessibility to scientific material has always been a challenging task and can be considered a major obstacle for full inclusiveness in education in the fields of science, technology, engineering and mathematics (the traditional STEM subjects), in particular at the late secondary and tertiary stage. Traditionally mathematical content was made accessible either via audio books recorded by subject specialists, or by manually generating different print-like formats, e.g., large print, Braille, high contrast, etc.  As teaching moves more and more towards the provision of online material and courses, the traditional means of making content accessible are all but obsolete. To avoid the risk that modern technology might create an even higher obstacle for inclusive education, it is important to ensure accessibility of scientific web content without the need for expensive, specialist software. 

Dr Volker's research concentrates on making mathematical formulae accessible for visually and print impaired readers, which is part of a larger body of work on providing assistive technology solutions for STEM content. Since formulas can be generated in many ways, from a variety of markup languages (LaTeX, AsciiMath, MathML, etc.), and formulas with the same visual appearance can be constructed quite differently, an important pre-requisite for generating homogeneous and meaningful presentations in alternative formats such as speech, Braille or as interactive applications, is a semantic analysis and reconstruction of the presentation form. Hence at the core of his work is the definition and generation of a semantically rich representation by means of pattern recognition techniques and domain-specifically selected heuristics. This serves as a basis for innovative creation of alternative formats.  Since modern web technology enables embedding of sufficient hidden semantic information, content can not only be made accessible in a traditional way, but allows for a manifold of personalisable views that can support learners with diverse special needs.  All these ideas are implemented in a system Speech Rule Engine (SRE) and practically tested in the MathJax library for rendering mathematics in web browsers.