use warnings;
use strict;

use Data::Dumper;

package Blah;

sub new {
    my ($class, $browser) = @_;
    return bless {browser => $browser}, $class;
}

package main;

# the example you're interested in is below

my %screenshots;

for my $browser ('ie', 'ff', 'chrome'){
    $screenshots{$browser} = Blah->new($browser);
}

print Dumper \%screenshots;