What’s the Deal with Window Treatment Opacity? (Light Control)

Do you remember learning about the term “opaque” from grade school science class? If something’s “opaque,” you can’t see through it, right?

For example, your walls are opaque. However, your window’s glass is not.

With blinds, for the most part, you don’t get different opacities. They’re opaque and don’t let light through.

Now when it comes to shades, the term gets confusing. There are different levels of opacity. And for your reference, the industry often uses “light control” to mean the same thing as “opacity.”

Makes sense, though, doesn’t it? Without thinking about it, pretty much everyone knows what “light control” refers to.

When you encounter this term while shopping for shades, many products have different levels of “light control.” Some let a lot of light in, while others block the majority of it out.

We’ll explain what these light control terms most commonly refer to when used:


These blinds control light, but they don’t darken your room so well. They’re more for rooms where you know you want a fair amount of light, but maybe you want to block some out too.
They work better for living rooms than bedrooms, for example. With these blinds, a sheer attaches to each vane, which purposefully helps allow light in your room.

Of all the opacities discussed on this list, they let in the most light, allowing you to see outside best, but also reducing your privacy most.


They’re the same idea as sheer shades, but they let a little more light in.

Light filtering

You see this option most often with roller shades. Not only do they help control light, but they also preserve your view outside. However, because they still let in a fair amount of light, they’re not the best for protecting your privacy.


These shades almost entirely block all light from entering your room. Note that no shade can be designed to block 100% of all light. However, these take care of 99% of your light and work well in media and bedrooms.

Room Darkening

– Shades in this category block less than 99% of all natural light. Just like their name sounds, they darken your room to varying levels. Most often, you’ll see cellular shades used as room darkening shades because they’re the best at it.


You see this term used in reference to solar shades. The higher the percentage, the more light they let in and the less privacy you have. But, you can see outside easier. You can get these shades with a 1% openness factor.

You will see some companies use this “opaque” interchangeably with “blackout.” In general, consider it a term that refers to all these previous terms as a whole.

Confusing? Yes.

Necessary? No.

If you’re not sure, always ask the blinds company you talk to what they mean with different terms.

But hopefully, this sheds some light on the issue for you.