Getting new glasses has always been an at least partly offline experience. You can order frames and even lenses online — if you have the results of a recent eye exam handy. But at some point you have to leave the house and go take an eye exam.

Until now, apparently. Opternative, a company offering online eye exams, launched today. Opternative says it’s the only online eye exam that can deliver a physician-approved prescription for glasses and contacts.

Running a mobile phone app in conjunction with a desktop app, consumers can take an online refractive eye exam in less than 25 minutes.

The Opternative eye exam costs $40 for either a glasses or contact lens prescription or $60 for both. Patients receive an Ophthalmologist-issued prescription within 24 hours.

The Chicago-based company says that a clinical trial demonstrated the Opternative eye exam is just as accurate as a traditional office exam.

One report says that 67 million adults in the U.S. have not had a recommended eye exam within the last two years, due to inconvenience or cost issues.

Opternative isn’t the first startup to see a big opportunity in on-demand optometry. Another company (with a better name), called Blink, launched a service providing eye exam house calls in New York City earlier this year.

Currently, Opternative is available in 27 states, covering 75 percent of the population aged 18-40 years old, and is planning on expanding.

Opternative was founded in 2012. The company took a million in funding in a February 2014 in a round led by Chicago Ventures, Tribeca Venture Partners, and Lakewest Venture Partners.