Signature Guide

A small rectangular card, typically credit-card sized, with a cutout opening that enables blind people to write or sign in a straight line on paper. Signature guides are one of the simplest and most widely used low-tech assistive tools for blind people, providing a tactile frame that constrains the pen to a defined area. While traditionally used only for signatures, researchers have augmented signature guides with computer vision markers to enable more complex tasks such as filling out multiple form fields on printed documents, guided by smartphone-based audio instructions.