Because of the number of visa applications and the need for thorough security reviews, the visa application process may take several months. SPIE strongly encourages travelers to apply for their visas as early as possible (at least three to four months before the visa is needed).
SPIE recommends that you secure your travel visa before registering for the conference as cancellations after the registration refund cutoff will result in denial of your registration funds.
Passport requirements to enter the United States
US State Dept. Visa Information
US Department of Homeland Security
US Customs and Border Information
International Visitors Office
Visa Waiver Program (VWP) and Electronic System for Travel Authorization (ESTA) FAQs
Visitors to the US from visa-waiver countries, most of which are in Europe, are required to have an e-Passport, register online, and be screened and authorized for entry through the Electronic System for Travel Authorization (ESTA) program.
Electronic Visa Update System (EVUS) FAQs
As of 29 November 2016, new electronic registration requirements are in effect for Chinese citizens.
How to request an invitation letter
Visa background information
Because of the number of visa applications and the need for thorough security reviews, the visa application process can take several months. SPIE strongly encourages travelers to apply for their visas as early as possible (at least three to four months before the visa is needed).
Contact the nearest US consulate or embassy for details on visa application procedures.
Guidelines for successful visa applications
Information to take to the interview
Even those who have traveled frequently to the US for business purposes might encounter difficulties from time to time that might have little to do with their standing as individuals. The nature of the products and/or industry in which they have become involved such as certain types of US controlled goods (wireless technology, electronics, and such) may give rise to difficulties and/or delays. The political climate and current state of relations between the nations may become a factor. In other words, a prior history of travel to the US is never a guarantee of future admission.
SPIE does not have any influence with the US Department of State or the Office of Homeland Security. If your visa is delayed (60 days or longer) or denied, please contact the consulate where your application is being processed. Also, please contact the National Academies International Visitors Office and fill out the questionnaire.
The International Visitors Office regularly reports to the State Department (submitted through the visa questionnaire) about applications that have been pending for longer than 60 days.