The Field Permissions module allows site administrators to set field-level permissions to edit, view and create fields on any entity.

Features

Enable field permissions on any entity, not just nodes.
Role-based field permissions allowing different viewing patterned based on what access the user has.
Author-level permissions allow viewing and editing of fields based on who the entity owner is.
Permissions for each field are not enabled by default. Instead, administrators can enable these permissions explicitly for the fields where this feature is needed.
Field permissions overview

Instructions

Once Field Permissions module is installed, you need to edit the field settings form to enable permissions for each field where you need this feature. You can enable any of the following permission types:

Create own value for the field
Edit own value for the field
Edit anyone's value for the field
View own value for the field
View anyone's value for the field

Use these options to enable role based permissions for each field. When permissions are enabled for a particular field, access to this field is denied by default and explicit permissions should be granted to the proper user roles from the permissions administration page. On the other hand, when these options are disabled, field permissions are inherited from node view and/or edit permissions. In example, users allowed to view a particular node will also be able to view this field, and so on.

Notable Credits

RTBC issues for Field Permissions

Filters