Letter of Invitation

The visa application process to enter the United States has become subjected to greater degrees of scrutiny than in the past. For this reason, the application process can take up to six months or more. You will need to apply for your visa as early as possible but no later than three months before you wish to enter the United States. Invitation letters take FiO/LS Management 7-10 days to process.

One factor contributing to the increase in the processing time is a personal interview that is now required for most applicants as a standard part of visa processing. Once it is known that a visa is necessary for travel, the individual needs to contact the embassy or consulate to schedule an appointment for screening.

For detailed information about applying for a visa refer to the U.S. Department of State website and the National Academies International Visitors Office website.

Individuals requiring letters of invitation to obtain travel visas may contact FiO/LS directly by one of the following methods:

  1. Apply Online

  2. Fax: +1 202.416.6100

  3. Mail: FiO/LS Management – Invitation Letter
    Optical Society of America
    2010 Massachusetts Ave., NW
    Washington, DC 20036

Please include your full name as it appears on your passport, complete mail address and phone and fax numbers and indicate which meeting you will be attending. If you are presenting a paper, include the title and session in which  the paper will be presented, or if you are exhibiting, please indicate so in your request. When requesting letters for more than one individual, please include all of the information that is requested above for each person. Individuals from China should include the passport number, date of birth and gender of the person requesting the invitation letter. All letters of invitation will be sent by airmail or by fax, unless a Federal Express account number or credit card number with an expiration date is provided on the original request. Please allow ample time for processing requests.

OSA is not able to contact U.S. embassies in support of an individual attempting to gain entry into the host country to attend the conference.

If you have questions about this process please email invitations@osa.org.

The U.S. Department of State has added a new feature to its website regarding visa wait times. Since visa applications are under greater scrutiny, the State Department is advising those who wish to travel to the United States for business or other nonimmigrant purposes to plan ahead. The site now provides estimated waiting periods to get an interview to apply for a visa and the estimated time it will take to process the application at the consular section. The visa wait times are shown for various locations around the world. The State Department advises that it is best to check with the local embassy or consular section to confirm the information. To obtain information on wait-times site, go to http://www.travel.state.gov/visa/tempvisitors_wait.php.