How to accept only date as input field value for bootstrap datepicker in angular

html

                 <form name="eventInformation" id="eventInformation"><label class="required"> Occurence Date </label>
                     <p class="input-group">
                       <input type="text" class="form-control" uib-datepicker-popup="{{format}}" ng-model="formData_EventDetails.eventOccurDate"
                              is-open="popup[0].opened" datepicker-options="dateOptions" close-text="Close" required/>
                    <span class="input-group-btn">
                    <button type="button" class="btn btn-default" ng-click="open(0)"><i class="glyphicon glyphicon-calendar"></i></button>
                    </span>
                    </p>

                <div class="col-sm-2 pull-right">
                          <button class="btn btn-block btn-primary ebtn"
                                  ng-disabled="eventInformation.$invalid"
                                  ng-click="submit()">Save</button>
                      </div>
</form>

javascript

                        $scope.format = 'yyyy/MM/dd';


                        $scope.dateOptions = {
                            formatYear : 'yy',
                            startingDay : 1
                        };

                        $scope.popup = [];
                        for (i = 0; i < 10; i++) {
                            $scope.popup[i] = {
                                opened : false
                            };
                        }

                        $scope.open = function(i) {
                            $scope.popup[i].opened = true;
                        };

I have bootstrap datepicker element which i am trying to only accept date as input, but it accepts all kinds of inputs i.e. string, numbers etc. How can i limit so it only takes date as input