The visa application process to enter the United States has become subjected to a greater degree of scrutiny. 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.
One factor that increases the processing time is the personal interview, now required for most applicants as a standard part of visa processing. As soon as you know that you will need a visa for travel, you should contact the embassy or consulate to schedule an appointment for screening.
For detailed information about applying for a visa, refer to the Department of State website and the National Academies International Visitors Office website. Individuals requiring letters of invitation to obtain travel visas may contact OSA directly by one of the following methods:
Optical Society of America, Meetings Department
2010 Massachusetts Ave., NW
Washington, DC 20036-1023 USA
Please include your full name as it appears on your passport, your complete mailing address, and your phone and fax numbers. Be sure to indicate which meeting you will be attending. If you are presenting a paper, include the title and the session in which that paper will be presented, or if you are exhibiting, please indicate that in your request. When requesting letters for more than one individual, please include all information above for each person. Individuals should include passport number, date of birth and the gender of each person requesting an invitation letter. All letters of invitation will be sent by email or fax unless a Federal Express account number or credit card number with expiration date is provided on the original request. Please allow ample time for processing requests. OSA is not able to contact US Embassies in support of an individual attempting to gain entry into the host country to attend an OSA meeting.
Electronic System for Travel Authorization (ESTA)
As of 12 January 2009, all nationals and citizens of Visa Waiver Program (VWP) countries will be required by law to obtain a travel authorization prior to initiating travel to the United States under the VWP. This authorization may be obtained through the Electronic System for Travel Authorization (ESTA), a free internet application administered by the Department of Homeland Security though a U.S. government Website.
Register Online for entry to the United States
Visa Waiver Program Frequently Asked Questions
*The Visa Waiver Program FAQ's contain a list of countries that are a part of the VWP.