225 ILCS 80/18

The Department may, in its discretion, license as an optometrist, without examination on payment of the required fee, an applicant who is so licensed under the laws of another state or jurisdiction of the United States. The Department may issue a license, upon payment of the required fee and recommendation of the Board, to an individual applicant who is licensed in any foreign country or province whose standards, in the opinion of the Board or Department, were, at the date of his or her licensure, substantially equivalent to the requirements then in force in this State; or if the applicant possesses individual qualifications and skills which demonstrate substantial equivalence to current Illinois requirements. Applicants have 3 years from the date of application to complete the application process. If the process has not been completed in 3 years, the application shall be denied, the fee forfeited and the applicant must reapply and meet the requirements in effect at the time of reapplication.