html wont render using ng-bind-html-unsafe - html

Question

i was able to break string to chars array and surround each char in <span></span> but when im trying to pass this array to table the html wont render.
breaking the string:
//parse cron_format and edit each digit individually
$scope.parse = function (cron_format){
var parsed = cron_format.split('');
for(var i = 0; i < parsed.length; i++) {
parsed[i] = '<span>' + parsed[i] + '</span>';
}
return parsed;
}
when i try to create the table like this:
<table class="table table-bordered table-hover">
<thead>
<td>user name</td>
<td>script name</td>
<td>cron format</td>
</thead>
<tbody ng-repeat="(user_id,script_id) in data | filter: test">
<tr ng-repeat="(script_id, cron_format) in script_id">
<td>{{user(user_id)}}</td>
<td>{{script(script_id)}}</td>
<td ng-bind-html-unsafe="{{parse(cron_format)}}"></td>
</tr>
</tbody>
</table>
there are no values in cron_format:
without trying to render -> <td>{{parse(cron_format)}}</td>
the table looks like this:
what am i doing wrong?
UPDATE:
i changed function's two last rows :
$scope.parsed.htmlSafe = $sce.trustAsHtml(parsed.html);
return parsed;
and i get this error:
Can't interpolate: {{parse(cron_format)}}
TypeError: Cannot set property 'htmlSafe' of undefined
can someone explain whats the mistake im doing here?