Índice
TL;DR
- General rule is to position yourself so that the screen is facing perpendicular to the window, not towards it or with the window behind it. (osha.gov)
- Assuming you don’t want to rearrange the whole room to make this happen, small adjustments (getting higher up, monitor + chair height, maybe blinds/curtains, and a monitor arm) tend to be a better (and cheaper) fix than buying new gear.
- Check that it worked by opening a bright white screen, and seeing if the whites become a bright “patch” on your screen visible at the times you typically work.
Why side lighting produces reflections, and why it feels worse than you expect
A monitor is basically a dark glossy (or semi-gloss) surface. A bright light source, typically sunlit, lands upon it from the side, producing specular (mirror-like) “hot spots” or a comprehensive “washout” that reduces contrast. In order for the brightness to stop hitting your eyes, you have to squint, lean, or crane your neck to find an angle where the brightness no longer appears, exactly the kind of “fix” that increases eyestrain and skews posture over time. (osha.gov)
Side glare also tends to change as the day goes on: morning and late afternoon sun tends to land at lower angles, so even a “fine” setup at noon may be unworkable later in the day.
The correct direction for the desk and monitor relative to the window is to place the monitor perpendicular to the window (screen at right angles to window). This should substantially lessen the chances that the window’s area apparent to your eye will directly reflect back into your eyes from the monitor.
- Good: Window to your left or right, monitor rotated so screen is at right angles to window.
- Avoid: Window directly in front of monitor (you have to look towards the bright window). (dundee.ac.uk)
- Avoid: Window directly behind monitor (light shines on face and reflects off the monitor). (dundee.ac.uk)
If you remember nothing else: do not try to fight glare with your body. Dim glare by changing angles (screen/window/light) and not by leaning, twisting or bowing your head.
What “perpendicular to window” looks like in real rooms
In many home offices, the easier solution is to place the desk so the window is on left or right, then rotate monitor so its face is not turned toward the glass. Even a 10–20° rotation might make the difference between seeing reflections and seeing clearly.
Quick test: is the window indeed the cause of your glare?
- Open a bright, mostly white screen (empty document or a white webpage).
- Sit as you normally do and look for bright shapes on the display (rectangles, streaks, a sort of hazy patch).
- Turn your head a bit left/right, without moving the chair. If glare changes quite a bit it’s probably an angle with the window/light.
- Momentarily block window with a curtain or even blanket for 1 min. If glare is gone, you’ve pinpointed the cause. Repeat this check at the times you actually work (e.g. 9 am, 1 pm, 4 pm). The angle of the sun changes and later in the afternoon you can get what’s often called “mystery glare”.
Fixes from fastest to best (without getting a new desk)
- Adjust blinds/curtains first (control the source). If the window is bright enough to reflect on your screen you need some way to reduce its brightness directly: blinds or shades or curtains. Sheers: Take the edge off but still allow daylight (ideal on overcast days). Blackout curtains: best where the sun strikes the window directly (good for video calling also). Adjustable blinds: Allow aiming light up onto the ceiling and off the desk (usually the best option) (osha.gov).
- Rotate the monitor (sometimes chair also) 10–30°. If the window is doorside, you may be very close to the ideal, but if your screen face itself is angled slightly toward it, then it is creating a “clean path” onto the screen for reflection. Rotate slightly away from the window until you see reflection move off the actual screen. (osha.gov)
- Get that screen deeper into the room (away from the window). If your monitor is in a windowed corner or is placed very close to it, the brightness differences are great (and can change as you work at your desk.) If you can, pull it a bit away from the window wall. Some guidance explicitly says not to place screens too near windows on this basis. (dundee.ac.uk)
- Fix your screen angle (but don’t trust tilt alone).
Minor tilt changes can help—especially to combat overhead lights—but glare from side windows is usually handled by rotation and window control. Also, over-tilting can cause new reflection from ceiling lights. (osha.gov) - Add ‘bias lighting’ behind the monitor (balance contrast).
A dim light behind the monitor (pointed at the wall, not the screen) can reduce the overall contrasty feel of the scene, and that’s often easier on the eyes. Won’t remove reflections, but can make very bright windows less uncomfortable. - Consider an anti-glare filter only after referring to angles.
Anti-glare filters can reduce reflected light on the monitor. Some workplace guidance includes this as an option. The tradeoff is that a filter may also cut some sharpness or brightness a little, so it’s better to think of them as a “last mile” solution after improving angles and closing the blinds. (osha.gov)
| Your window is… | What you’ll notice | Best move | Why it works |
|---|---|---|---|
| To the side (left/right) | Glare comes and goes as the sun moves; brightness on some part of the screen part of the time | Rotating the monitor so it is truly perpendicular to the window, adding blinds if necessary. | Breaks path of direct reflection, and reduces brightness of window when required. (osha.gov) |
| In front of you (you face it) | Screen looks all washed-out and you feel like you are “looking into brightness” | Turn desk, and monitor on it, so that the monitor is at right angles to the window. Use blinds. | Reduces contrast and reflection, and you are not looking toward the brightest surface. (osha.gov) |
| Behind you | Your face on webcam appears “lit up”; onscreen is a ‘ghost’ of the window | Move the desk so that the window is to the side. If not feasible, use blackout curtains, possibly a monitor hood. | Prevents light shining directly towards screens and eyes. (dundee.ac.uk) |
| In a corner (two windows) | Impossible to completely control at certain periods | Start with the brighter window. Ensure the computer screen is perpendicular to that. Pull the other window’s blinds/curtains as needed. | You are taming the biggest source of glare first (rather than both). |
| You can’t move anything (tiny room) | One ‘bad’ hour makes work miserable | Curtains/blinds + small rotation + raise brightness slightly during glare hours | When geometry is fixed, controlling brightness and micro-angles is your best lever. (osha.gov) |
- Buying a brighter monitor instead of fixing the window/screen angles (the reflection is still there).
- Placing a desk lamp behind or directly in front of the monitor (it can create a new reflection). (healthservice.hse.ie)
- Tilting the monitor back so far that it starts reflecting ceiling lights. (osha.gov)
- Using a glossy screen in a very bright room without any window coverings.
- Ignoring time-of-day: you test at noon, but you work during morning/afternoon glare hours.
How to verify your new position is correct (a simple before/after test)
- Take a photo of your screen glare (with the window visible in the background if possible).
- Apply one change at a time (rotate monitor, close blinds, move desk slightly).
- Re-check using the same bright white screen and the same sitting posture.
- Confirm at your two worst glare times of day. If you still see glare, keep rotating until the reflection moves completely off the main work area; then fine-tune with blinds.
Informational note: If you’re getting frequent headaches, dry eyes, or persistent eye strain even after glare is controlled, consider taking regular visual breaks and discussing symptoms with an eye care professional.
FAQ
Should my desk face the window?
Usually not, if it causes glare or makes you look toward a bright surface. A safer default is to keep the monitor perpendicular to the window (screen at right angles), then use blinds/curtains as needed. (osha.gov)
If the window is already to the side, why am I still getting reflections?
Because the monitor is often slightly angled toward the window, or the sun angle is low (morning/late afternoon). Rotate the monitor 10–30° and add adjustable window coverings for the hours when sunlight hits directly.
Will tilting the monitor fix side-window glare?
Tilt can help with overhead reflections, but side-window glare is more reliably solved by rotating the screen (changing left/right angle) and controlling the window brightness. (osha.gov)
Are anti-glare filters worth it?
They can help reduce reflections, and they’re commonly listed as an option—especially when you can’t change the room layout. But try positioning and blinds first, because filters can slightly reduce clarity/brightness. (osha.gov)
What about two monitors?
Treat your ‘main’ monitor like the priority target: keep it perpendicular to the window. If the second monitor must sit at an angle, use blinds/curtains and consider a monitor arm so you can reangle both screens throughout the day.
My desk lamp also causes glare—where should it go?
Place task lighting to the side of the monitor so it lights your desk surface without reflecting on the screen, and angle/shade it away from your line of sight. (healthservice.hse.ie)
Referências
- OSHA eTools – Computer Workstations: Monitors (includes tip to place monitor perpendicular to window) — https://www.osha.gov/etools/computer-workstations/components/monitors
- OSHA eTools – Workstation Environment (lighting, glare, windows; right angles to windows) — https://www.osha.gov/etools/computer-workstations/workstation-environment
- HSE Health Service (Ireland) – Office safety and display screen equipment (avoid glare; task light to side) — https://healthservice.hse.ie/staff/health-and-safety/office-safety-and-display-screen-equipment/
- University of Dundee – Display Screen Equipment safety policy (screen at right angles to windows; avoid in front/behind) — https://www.dundee.ac.uk/corporate-information/display-screen-equipment-safety-policy-arrangement
- OSHA eTools – Checklists: Evaluation (glare not reflected on screen) — https://www.osha.gov/etools/computer-workstations/checklists/evaluation