1. Visual Span: This refers to the amount of information that can be perceived at a glance. It's related to peripheral vision and how much we can see at the edges of our visual field.
2. Eye Tracking: This is a technology that tracks the movement of someone's eyes, often used in research to understand how people interact with websites, read text, or engage with visual stimuli.
3. Reading Span: This refers to the number of words a person can recall after reading a short passage. It's a measure of working memory and reading comprehension.
4. Attention Span: This refers to the amount of time a person can focus on a particular task. It's a measure of concentration and mental stamina.
If you can provide more context about how you encountered the term "eye span," I might be able to give a more specific answer.