I read PowerShell.com’s blog get display name out of user name in a one line.
Here is a quick way to find the current user in your Active Directory and retrieve account information such as the display name:
([adsisearcher]"(samaccountname=$env:USERNAME)").FindOne().Properties['displayname']
I have even found easier way than using Active Directory PowerShell Module.
(Get-ADUser $env:USERNAME).name