regex query for mongodb in PHP

Question

Normal regular-Expression query for MongoDB is faster in console mode. For example customer name start with "Ale": this following query is very faster.

db.labels.find({ "customer.name": { $regex: /^Ale/i } },{"label.name":1})

but once i try this same kind of query in PHP its take huge time to load:

    $page =int($_request["p"])
    $limit = 20;
    $skip  = ($page - 1) * $limit;
    $next  = ($page + 1);
    $prev  = ($page - 1);
    $name = "Ale";
    $regexObj = new MongoRegex("/^".$name."/i"); 
    $where = array("customer.name" => $regexObj); 
    $sort  = array('customer.id' => -1);
$result = $collection->find($where)->skip($skip)->limit($limit)->sort($sort);

When i remove $where condition from the query it runs very faster. But ofcorse i need the $where.

Any suggestion or any solution will be appreciated!