While working with text in XR there are some essential things to keep in mind when it comes to how we perceive the text. The factors mentioned below play a crucial role in how we select and do typesetting of text in XR experiences.
Visual Acuity: commonly describes the clearness of vision. Visual acuity is dependent on optical and neural factors:
- The sharpness of the retinal focus within the eye,
- The health and functioning of the retina, and
- The sensitivity of the interpretative professors of the brain.
Spatial Frequency: refers to the level of details present in an image (stimulus) per degree of visual angle. A letter with small details and sharp edges contains higher spatial frequency as compared to a simplified letter with round edges.
Crowding: is the effect of separation which hinders the reading, it is a perceptual phenomenon in which recognition of letters presented away from the fovea (centre of gaze) is impaired by the presence of neighbouring letters
Foveal and parafoveal reading: Human eyes do not move continuously along a line of text while reading; instead, they jump across the line in rapid movements (known as saccades), between these saccades the eyes stop for a fraction of seconds (fixations). During this process, the Foveal area is where the fixation happens and the user focuses on that area however the parafoveal region helps in continuous reading