---
title: "Sleep Masks — Blackout and Contour Design"
description: "How sleep masks block light, why contoured designs help REM eye movement, and silk versus cotton face materials."
url: "https://bedguide.co.uk/environment/sleep-masks/"
category: "environment"
primary_entity: "sleep mask"
date_published: 2026-08-03
date_modified: 2026-08-03
---

# Sleep Masks — Blackout and Contour Design

> Sleep masks reduce light reaching the eyes to support darkness cues for sleep. Blackout performance depends on fabric opacity, edge seal, and nose-bridge fit. Contoured masks hold fabric off the eyelids so eyes can move during REM without lid pressure. Silk faces feel smoother. Cotton is breathable and easy to wash.

Materials covered: opaque foam or fabric cores, silk, cotton, elastic or adjustable straps.

## Light-blocking factors

1. **Opacity** of the core material.
2. **Edge seal** at nose, temples, and cheeks.
3. **Strap tension** — too tight causes pressure; too loose leaks light.

## Flat vs contoured

| Design | Eyelid contact | Typical use case |
| --- | --- | --- |
| Flat panel | Higher | Simple travel blackout |
| Contoured / 3D | Lower | Wearers sensitive to lid pressure in REM |

## Related BedGuide entries

- [Earplugs and white noise](/environment/earplugs-and-white-noise)
- [Pillow ergonomics](/bedding/pillows-ergonomics)

## Frequently asked questions

### Why use a contoured sleep mask?

Contoured masks keep material off the eyelids so the eyes can move during REM sleep with less pressure. Flat masks can feel restrictive for some wearers even when they block light well.

### Is silk better than cotton for sleep masks?

Silk is smoother and lower-friction against skin and lashes. Cotton is breathable and usually simpler to wash. Blackout performance still depends on the opaque core and edge fit, not the face fabric alone.

---

Source: https://bedguide.co.uk/environment/sleep-masks/ · BedGuide — educational encyclopedia, no affiliate commission. Facts checked against official sources where possible; see https://bedguide.co.uk/editorial-policy. Report an error: https://bedguide.co.uk/corrections.