Machine readable code combining preprinted indicia with hand-mark data

摘要

A method of entering a hand-marked response into a system by altering a predetermined modified bar code symbol in a manner so that the bar code is rendered readable. In this manner, bar code reading devices can be utilized to detect the hand-marked response. In an alternative embodiment, one of several potential responses may be marked and rendered non-decodable. A bar code reading device determines which of the several responses has been hand-marked by ascertaining which is non-decodable. Marking the response sheets may be aided by using an opaque template sheet or using a pressure sensitive overlay sheet.