Fields by Ticket
You can set your event registration form with personalized fields based on the registrant's selected tickets. In the form field setting, you can choose the fields you want to apply for a particular ticket type. (For example, the "Member ID" field can only be collected for the Member ticket type. Non-members wouldn’t have to fill in the “Member ID” fields)
From the main page, go to My Event -> Manage -> Settings
Choose the Registration Form and see the Advanced Form Settings under the Standard Fields.
Here’s some example of creating a field that will be set to one of the ticket type
Click on the Edit button in Fields by Ticket and set which of the existing fields you want to customize for the ticket type.
Click on Save Changes to implement the settings. See the final results in the final registration form
Read More about Unique Field