Angular's ngPattern allows you to validate input using a pattern. See below for an easy example of how to validate an e-mail address using the ng-pattern.
<input name="employeeEmailAddress" type="text" ng-model="employeeEmailAddress" ng-pattern="/^(0[1-9]|[12][0-9]|3[01])[\/](0[1-9]|1[012])[\/](19|20)\d\d$/" />