Visa Information
Letter of Invitation
If you are not a U.S. citizen and plan to attend the Optica Biophotonics Congress in person, advance planning is crucial.
Citizens of some foreign countries will need a visa to enter the United States and attend the Biophotonics Congress. Due to U.S. State Department regulations, U.S. embassies and consulates typically require a face-to-face interview for most non-immigrant visa applications.
Schedule Your Interview
There is no required documentation to schedule your face-to-face visa interview; you do not need to be registered, have a hotel reservation, or have a travel itinerary to make an appointment. OPTICA strongly suggests that all international travelers schedule face-to-face interviews as soon as possible.
Please note: While travelers should schedule their appointment as soon as possible, the appointment itself should take place after registering for the Biophotonics Congress. Visa letters for the congress will become available once registration opens. Registration for the Biophotonics Congress opens late December 2025.
To schedule an interview for the visa application process, please contact the nearest U.S. embassy or consulate. For more information, please visit travel.state.gov/content/visas/en.html.
For current visa wait times, please visit https://travel.state.gov/content/travel/en/us-visas/visa-information-resources/global-visa-wait-times.html.
You should receive an invitation letter via email shortly after completing the form. For questions about invitation letters, send an email to invitations@optica.org.
Visa Information
If you need a travel visa, begin the visa application process now. The application process can take up to six (6) months or more. We strongly encourage you to apply for your visa as early as possible, but no later than three months before you wish to enter the United States. Strict security requirements may cause delays in visa processing.
Learn more about the visa application process. >
Resources
- U.S. Customs and Border Information
- VWP and ESTA: Frequently Asked Questions
- U.S. State Department Visa Information
- Department of Homeland Security
- National Academies International Visitors Office
ESTA Application
ESTA is an automated system that determines the eligibility of visitors to travel to the United States under the Visa Waiver Program (VWP). Authorization via ESTA does not determine whether a traveler is admissible to the United States. U.S. Customs and Border Protection officers determine admissibility upon a traveler's arrival. The ESTA application collects biographic information and answers to VWP eligibility questions. ESTA applications may be submitted at any time prior to travel, though it is recommended that travelers apply as soon as they begin preparing travel plans or prior to purchasing airline tickets.
