A11y View: Geometric Optics

About the A11y View Tool

The A11y View is a design and presentation tool that we use to visually review and demonstrate the Interactive Description design of a simulation. The descriptions we design live within our accessibility layer, we call the Parallel DOM, or PDOM. The HTML of the PDOM provides document and interaction semantics for State Descriptions (copied into the blue box), and timely delivery of Responsive Descriptions (copied into the orange box). For a learner accessing the simulation with screen reader software, the State Descriptions provide on-demand access the current state of simulation while Responsive Descriptions deliver relevant changes - in real time - as the learner interacts with the simulation.

Please note that learners who use screen reader software do not use this A11y View, they use the same simulation that all learners use.

Activity log of Responsive Descriptions

About Responsive Descriptions

Responsive Descriptions deliver changes made to interactive objects (Object Responses) and changes to the surrounding context (Context Responses). Only responses powered by ARIA Live appear in the activity log below, and most are Context Responses. Most responses powered by ARIA Live are delivered politely, but some are really important so we make them assertive (occasional line highlighted in pink). Note that many Object Responses are delivered using the aria-valuetext attribute (see grey text under slider interactions in the blue box).

State Descriptions for Geometric Optics

About State Descriptions

State Descriptions provide on-demand access to a full description of the current state of the simulation. This lengthy description is accessible to the learner from the moment the simulation loads, and during any point as they explore. The dynamic parts of the State Descriptions update silently as the learner interacts and makes changes.