Comparing Projector’s Lux vs. Lumens: What Is the Difference?

We explain the way the brightness of projectors is measured and break down the difference between lux and lumens units.
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As consumers are getting more and more sophisticated, it is essential that every product is described in detail. Their features, what they can do, and what they cannot do should be stated in order to avoid confusion.

Speaking of confusion, the lux vs. lumen projector is a concept that needs to be talked about. Lux and lumens are commonly used by marketers while promoting projectors. Some of them confuse one for the other, thereby leaving consumers helpless. Lux and lumens are terms that are used to measure how bright a projector is, but as much as they are similar, they are also different.

So, in this article, we’ll be explaining to you what lux means, what lumens means, and the difference between the two. But before that, let’s see the possible ways of measuring the brightness of a projector.

How to Measure the Brightness of a Projector?

Comparing Projector's Lux vs. Lumens: What Is the Difference?When it comes to projectors, there are numerous terminologies and SI units for measuring brightness. They include:

  • Lux: A unit of measurement for the total amount of light that reflects on a surface.
  • Lumens: A unit of measurement of total light that reflects in all directions putting human eye sensitivity into consideration.
  • ANSI lumens: It’s a term for measuring the overall amount of light output by a projector. Most good projectors now make use of this.
  • Nits: A term for measuring brightness in terms of area or candela Trusted Source Candela - Wikipedia .
  • Foot-lamberts: It’s similar to Nits, but it’s basically used in the United States.

In this article, we’ll be focusing on the three widely and commonly used terms – lux, lumens, and ANSI lumens.

What Does Brightness Mean?

Brightness in photometry Trusted Source Photometry (optics) - Wikipedia refers to the light you get directly from a source and reflected light, like the light the screen you’re reading from right now is emitting.

Your projector brightness determines the clarity of images you’ll get.

What Does Lux Mean?

Lux is a unit of brightness that is measured in terms of surface area i.e., how much light reflects on a surface. It indicates how a human eye perceives light intensity by measuring how much incident light illuminates a surface.

Lux measures how bright a light appears after taking into account how it travels over an area. When you are close to your projector, the lux will be high, but when you are far away, the lux will be low. It has to do with distance.

However, distance won’t be a problem for people who have limited space in their homes, offices, or schools as they will get crisp visuals. For people with limited space, it’s best to make use of short throw projectors. These projectors will regulate the intensity of the light and give a fantastic view.

What Do Lumens Mean?

When you turn on your projector and reflect any content onto your screen, the amount of light visible to your eye is measured in lumens. It includes all the light the projector produces to make more vivid images.

To better understand lumens, you must understand luminous flux, which is the total amount of light emitted by a source per unit time. It’s also important that you don’t mix the meaning with radiant flux. While luminous flux is only used to describe the electromagnetic waves that can be seen with the naked eye, radiant flux measures electromagnetic waves from all sources, both the one that can be seen and the one that cannot be seen.

It is worth noting that you can’t judge the brightness of a projector with its lumens alone. The projector’s lumens only indicate how bright the light source is. It doesn’t put into consideration the actual lux (actual intensity of the light you will get).

Are ANSI Lumens the Same?

No, ANSI lumens are not the same as regular lumens. ANSI lumens use more variables in their calculations making them more accurate. With ANSI lumens, you will understand how to read the power of a particular projector better.

The American National Standards Institute (ANSI) defined ANSI lumens as a unit for measuring the overall amount of light output by a projector; in other words, the greater the projector’s lumens, the brighter the light it generates and the lower the projector’s lumens, the dimmer the light it produces.

How Bright Should a Projector Be?

How bright your projector would be is dependent on what you want to use it for. The brighter your projector, the more lumens you’ll need. With even the cheapest 4K projectors, you can still get quality brightness as they have many lumens. In fact, these projectors are the dominant standard type of projectors used in digital cinematography, tv, and consumer media.

So, to determine how bright you want your projector to be, you have to consider the lumens. These three factors – content to be displayed, resolution, and ambient light must be examined to know your preferred number of lumens. The video below explains it in more detail.

  • Content to be displayed: What you want to view through the projector determines how many lumens your projector is to have and how bright it will be. For example, if you want to display a document that has no images in a class or an office presentation, you don’t need a projector with many lumens. But if you will be displaying graphics, more lumens will be needed.
  • Resolution: To get clear visuals, your projector’s resolution must be high. 4k and 1080p are the most prevalent resolutions for home theaters. With less than $1000, you will get projectors that have a high resolution of nothing less than 1080p.
  • Ambient light: The number of lumens needed also depends on where you’re going to use your projector (indoor or outdoor). The amount of light that comes in contact with the screen tampers with the brightness you’ll get. The more environmental light that hits the screen, the more lumens the projector will need to provide sufficient brightness for good viewing, and vice versa.

To get optimum brightness, experts have recommended the use of EPSON Home Cinema for indoor use and GXX G1 Projector for outdoor movies.

Lux vs. Lumen Light Output of Projectors

To begin with, lux and lumens are both SI units used in measuring projectors’ brightness. They both quantify projectors’ brightness, but in two different ways. The quantity of light dispersed across a certain area is measured in lux, while the amount of light emitted from a source, taking account of human sensitivity, is measured in lumens.

The lumen is the quantity of light emitted from a light source, adjusted for the sensitivity of the human eye. Lux measures how bright a light appears after taking into account how it travels across an area. When it comes to projectors, 1 lux means 1 lumen per square meter.

When measuring lux and lumens from a fixed source, the lux will decrease with distance as the lumen will remain constant.

When purchasing a projector, the lumens should be considered first. The dispersion of an area’s effect on luminous flux must be taken into consideration. If the manufacturer or merchant does not display them but displays only lux, it’s a red flag that you need to be concerned about.

However, these two brightness measurements are critical when you’re on the lookout for a projector. With the knowledge of these two light units, you’ll be able to purchase a projector that will provide adequate light for a crisp image regardless of the distance.Comparing Projector's Lux vs. Lumens: What Is the Difference?

Final Thoughts

With your new knowledge about lux vs. lumens projector, we are sure that you can now make the best choice amongst the projectors on the market. Brightness determines how enjoyable your viewing experience will be, so it’s important that you incorporate the knowledge gained while going through projectors’ features.

Projector’s brightness units, lux and lumens, are similar in the sense that they’re both used to measure brightness. But they are also different as lux refers to the light that reflects on a surface and lumens means emitted light that takes into consideration human eye sensitivity. Lumens are very important in terms of light production.


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