Those Who Want to See Must Close Their Eyes

Squint Zoom

Eye closure can happen gradually - this example examines how a gradual closure of the eyes could be used as a means of interaction.

Background

Gradual closure of the eye, squinting, is a reflex upon exposure to bright light and also used to sharpen the view on something - when we squint, less light enters the eye; this makes the resulting image on the retina darker and smaller, but sharper. Squinting, while omitting the surrounding, sharpens the focus in order to reveal more detail. This principle could be used in human-computer interaction, as well.

For example, gradually moving into detail is used in graphics software when zooming into areas of interest of a picture.

Concept

I was interested in how a gradual element could be controlled through squinting - an uncommon task for the eyelids.

Here, we squint to zoom, while looking at an image. Squinting the eyes stronger zooms in further, whereas returning to normal looking restores the original zoom factor.

Implementation and user test ´

In this example, the act of squinting is technically tracked as a 'minor' eye closure. Once a certain threshold level is reached by an eye, the shortcut for 'zoom in' is triggered (Ctrl-'+'), while leaving the 'squint' status triggers the shortcut for 'zoom out' (Ctrl-'-'). It is so possible to zoom in on the image by squinting. The subjacent application was Adobe Photoshop 91.

The users were encouraged to use the mouse and move the image, as to combine the work of their eyes with the work of their hands.

Summary of findings

Squinting the eyes is a quickly executable command, yet it implies certain limitations: in the test group, it was perceived to be 'cramped' and unnatural, especially over time. It may be concluded that this principle could be valuable for 'quick looks' into detail, which must, however, be presented adequately for squinted eyes, especially in terms of display size and level of detail.

pro	con
speed of execution is very good intuitiveness	exhausting blurred perception

Squinting could well be used as an analogue input for previewing data representations on screen, ideally only of short duration and augmenting the existing workflows of the hands. This feature is available in the final implementation.