Screen Eyes

Windows blue-light filter — system tray app. No installers, no bloat, no phoning home.

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Screen Eyes reduces blue light from your screen by directly manipulating the display gamma ramp — the same API f.lux and Redshift use. It runs as a system tray icon, consumes almost no resources, and requires zero installation beyond downloading the files.

Quick Start

1. Download the latest release.
2. Right-click install.ps1 and choose Run with PowerShell. This creates Start Menu and Desktop shortcuts with the Screen Eyes icon.
3. Double-click the new Screen Eyes shortcut on your Desktop or find it in the Start Menu. The icon appears in your system tray.
4. Right-click the tray icon and choose a filter mode.
5. Done. It stays on until you exit.

After the first launch, you can delete install.ps1 — it's only needed once.

Windows may show a UAC prompt when Screen Eyes starts because gamma-ramp changes and the first-run registry fix require administrator rights. This is normal. The app itself runs silently after launch — no terminal window.

Starting on Boot

Run install.ps1 first (if you haven't already). Then copy the Start Menu shortcut:

1. Press Win+R, type shell:startup, press Enter.
2. Copy the Screen Eyes shortcut from your Desktop or Start Menu into the Startup folder.

Emergency Reset

Press Ctrl+Alt+R at any time to instantly restore normal screen colors.

You can also right-click the tray icon and choose Reset to Default.

Filter Modes

Mode	Blue level	Use case
Default / Reset	100%	Turn the filter off
Gentle Warm	70%	Daytime comfort, slight warmth
Dr. Jack Kruse - Day Warm	45%	Reduced blue during the day
Sunset Amber	28%	Late afternoon transition
Deep Red	4%	Night — still readable
Dr. Jack Kruse - Evening Red	2%	Strict evening, almost no blue
Dr. Jack Kruse - Night Red	0%	Blue channel completely off

Auto-Schedule (Dr. Jack Kruse Protocol)

When enabled from the tray menu, Screen Eyes automatically shifts your screen warmth throughout the day following Dr. Jack Kruse's circadian principles:

Time	Mode
06:00 – 07:59	Gentle Warm
08:00 – 16:59	Dr. Jack Kruse - Day Warm
17:00 – 19:59	Sunset Amber
20:00 – 21:59	Dr. Jack Kruse - Evening Red
22:00 – 05:59	Dr. Jack Kruse - Night Red

If you pick a mode manually while the schedule is on, the schedule pauses automatically so your selection sticks. Re-enable it from the tray menu any time.

Note: This is a wellness preference based on Dr. Kruse's published teachings — not medical advice.

How It Works

Screen Eyes uses the Windows SetDeviceGammaRamp API from gdi32.dll to reduce the blue channel in the hardware gamma lookup table. Each of the three colour channels (R/G/B) gets a 256-entry curve scaled by the mode's multiplier. The result is a warmer screen with no overlay, no injection, and no performance cost.

• Single-file PowerShell script — read it, audit it, modify it.
• No installer — just download and run.
• No telemetry, no internet access, no background services.
• Settings saved to %APPDATA%\Screen Eyes\settings.json.
• Gamma restored on exit via PowerShell exit handler.
• Multi-monitor support — gamma applied to every detected display.

Why This Exists

Existing blue-light filters are either:

• Paid (f.lux has a Pro tier, Iris charges)
• Invasive (installers, background services, telemetry)
• Unavailable (Windows Night Light is too mild for strict red-mode users)

Screen Eyes is free, open, invisible after launch, and the strongest red modes genuinely zero the blue channel.

Troubleshooting

Problem	Solution
Strong red modes don't apply	See NVIDIA / AMD fix below
Screen looks wrong / stuck	Press Ctrl+Alt+R
App won't start	Right-click the .vbs file → Run as administrator
Colours snap back to normal	Close GPU control panel apps (NVIDIA Control Panel, AMD Adrenalin)
Can't find the tray icon	Click ^ (overflow arrow) near the clock
Script execution policy error	Open PowerShell as admin: Set-ExecutionPolicy -Scope CurrentUser RemoteSigned

NVIDIA / AMD / Intel — Strong Modes Not Working

Some graphics drivers clamp the gamma ramp to prevent extreme colour shifts (this protects Windows Night Light). The fix is a single registry key — Screen Eyes sets it automatically on launch, but it only takes effect after a reboot:

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ICM
  GdiICMGammaRange = 256 (DWORD)

Reboot once after first launch. After that, all modes (including Night Red with 0% blue) will work. The app notifies you if a reboot is needed.

If modes still fail after reboot:

• NVIDIA: Open NVIDIA Control Panel → Display → Adjust desktop color settings → set Choose how color is set to Other applications control color.
• AMD: Close AMD Adrenalin software.
• Intel: Close Intel Graphics Command Center.

Files

Screen Eyes/
  ScreenEyes.ps1          # Main application (PowerShell)
  ScreenEyes.ico          # App icon
  install.ps1             # One-time installer — creates shortcuts
  Start Screen Eyes.vbs   # Silent launcher — no CMD window
  Start Screen Eyes.bat   # Debug launcher — shows console output
  README.md               # This file
  LICENSE                 # MIT license

Building from Source

No build step. The script is plain PowerShell — open it in any text editor.

The icon was generated with Python/Pillow. If you want to rebuild it:

pip install Pillow
python -c "
from PIL import Image, ImageDraw
# ... see make_icon.py in the release ...
"

Contributing

PRs are welcome. Keep it simple — no dependencies, no build systems. The whole app is one .ps1 file.

License

MIT — do whatever you want. See LICENSE.

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Screen Eyes is not affiliated with or endorsed by Dr. Jack Kruse.