PHP MongoDB Driver Query Only Specific Field From All Documents In Collection - php

Question

Ok, guys. As most of you might know, there is this new MongoDB Driver for PHP 7 out there. I was trying it out. I got stuck at this query here :
There is a collection like this:
{
"_id" : ObjectId("592d026e2a5e742704e60055"),
"name" : "One",
"conn" : [
{
"_id" : ObjectId("592d03cd3c83d5265c004d0b"),
"name" : "MongoDB Fans",
"comments" : "nice!"
},
{
"_id" : ObjectId("592d06513c83d5265c004d17"),
"name" : "SQL Fans",
"comments" : "not so nice!"
}
]
},
{
"_id" : ObjectId("592d0eec2a5e742704e60056"),
"name" : "Two",
"conn" : [
{
"_id" : ObjectId("592d0ef13c83d5265c004d37"),
"name" : "Cassandra Fans",
"comments" : "spooky!"
}
]
}
Now, what I want to achieve is this:
1. Find all "conn" fields (irrespective of which document they belong to) that contain a user input (say "xyz") in "name" as a sub-string.
2. Project the selected "conn" fields out.
I have tried using the following filters and options without success (Almost all of these return all the "conn" subsets instead of only the filtered subsets):
$filters = ["conn.name" => new MongoDB\BSON\Regex($name,'i')];
$options = ["projection" => ["_id" => 0,"conn" =>1];
$filters = ["conn" => ["\$all" =>["name" => new MongoDB\BSON\Regex($name,'i')]]];
$options = ["projection" => ["_id" => 0,"conn" =>1];
$filters = ["conn.name" => '/'.$name.'/i'];
$options = ["projection" => ["_id" => 0,"conn" =>1];
NOTE: I am using PHP 7 and the latest mongod PECL extension