FAQ
Ask the blunt questions.
Wavelength, medical claims, and whether a laptop is enough — answered without a costume.
Is this a medical device?
No. Red Light Display is a timed red field and a desktop tint, not a medical device. It does not diagnose, treat, cure, or prevent any condition.
Does it output 660 nm?
Display P3 red’s published dominant wavelength is about 614.9 nm, a color description, not a measured emission peak. The app cannot add a 660 nm LED or 850 nm near-infrared emitter.
What sessions are in the app?
The app includes a 15-minute session, 10-Minute Intense, 20-Minute Standard, Morning Red (same 15-minute timer as a morning option, not a circadian claim), Low Light (30 minutes at 35% Dark Red), Evening Wind Down, and Red Work (one click turns everything red). Red Work stays free for the launch promo, until further notice. One full session is free. Further sessions are locked behind Premium.
Is a laptop enough?
A laptop is not a dedicated panel. Output is calculated, not measured: about 0.2–0.3 mW/cm² at the glass. Equivalent dose or health outcomes have not been established.
Do I need an account?
No. Session data stays on the device. The optional launch list on this site only needs an email so we can tell you when Red Light Display is available.
What Mac do I need?
macOS 14 Sonoma or later, on an Apple silicon or Intel Mac. The beta also needs Apple’s free TestFlight app.
How do I install the beta?
Install TestFlight from the Mac App Store, open the Red Light Display beta link on the download page on the same Mac, then click Accept and Install in TestFlight.
Does Premium cost money in the beta?
No. In TestFlight, Premium purchases use Apple’s test environment, so you are not charged. A beta purchase does not carry over to the App Store release. Each beta build expires 90 days after it is uploaded. The Mac App Store price is a launch promo and is subject to change.
What does Premium unlock?
Further full sessions after the one free session, plus Display Boost, multi-display, red filter on every display, custom colors, saved routines, history, and display profiling. Premium is $9.99 once for the launch promo, plus tax at Apple checkout. No subscription. Price subject to change. Free keeps Red Work for the launch promo and one full session.
Is this a medical device?
No. It is not intended to diagnose, treat, cure, or prevent any disease. If the light is uncomfortable, end the session with Escape or Option-Command-Period. Do not use it if you have photosensitive epilepsy or light-triggered migraine unless a clinician has said it is appropriate.
My screen is stuck red
Press Option-Command-Period, or choose Restore Display Colors in the menu bar. That also ends a running session and stops the red filter. Or run: open -a "Red Light Display" --args --restore-display. If that fails, open System Settings → Displays and re-select the color profile.
Display Boost does nothing
Display Boost uses the HDR headroom of XDR displays (MacBook Pro 14/16 Liquid Retina XDR, Pro Display XDR). On other displays it has no effect and is hidden. A full-field session requests the sustained envelope (Apple’s 1000 nits class), not the 16× highlight peak. Idle current near 1.2 is not a granted envelope.
How do I get a refund?
Premium is a one-time App Store purchase. Refunds are handled by Apple under App Store rules. Email support@redlightdisplay.com if you need help finding the receipt. The price is subject to change.