Some critical industries and equipment are susceptible to light intensity and can damage due to extremely high or extremely low light intensity. It is essential to understand the intensity of light so that you can properly evaluate whether or not a space has adequate lighting conditions. This article will cover the basic working principle of lux meters light measurement and its importance.
What Is Lux?
Lux is the unit of the intensity of light. In simple terms, it is the measurement unit for luminosity.
Going a bit technical, you can call it a unit of measurement that describes the number of lumens falling on a square foot, which is called foot-candles, or on a square meter, which is called lux.
If there is a source of light comprised of 1000 lumens you have, and they get spread over the total surface area of 1 square meter, does this means you have a luminance of 1000 lux? Whereas, if the lumens get spread over the total surface area of 1 square foot, then you can say you have luminance lumens per square foot.
Light intensity is measured to ensure a certain standard of illumination is met. Some industries, sectors, and applications need a specific amount of luminance to carry out a specific operation or activity.
We’ll check out such applications in the coming sections of the article.
What Are Lumens?
Lumens (lm) are a measuring unit used to estimate the amount of light visible to the human eye. Lumens are basically the measurement of the luminous flux of a particular light source.
The most common occurrence of a lumen can be seen on a newly purchased light bulb or light device. You can see them explicitly mentioning the lumen output on the box. The higher the lumen output, the brighter the light source’s intensity. Similarly, the lower the lumen output, the less bright or lower intensity the light source.
It is common practice to purchase light bulbs based on their intensity or brightness, which means nothing but you are looking for the lumens.
With a thorough understanding of lumens, you can explore other lighting metrics, such as luminance and its crucial role in assessing the intensity of a light source.
Like an incandescent bulb, a light source emits light in all directions. This total measurement can be displayed as luminous flux. Lumens are not just a unit of light, but if you compare them against a given surface area, they become especially a more useful metric. Which moves us onto luminance?
Lux Meter Working Principle
Most of the lux meters consist of a body, photocell or light sensor, and display. The light that falls onto the photocell or sensor contains energy that is converted to electric current. The amount of current, in this case, depends on the light that strikes the photocell or light sensor. Lux meters read the electrical current, calculate the appropriate value, and show this value on its display.
Analog lux meters display values on a dial, usually with a needle or pointer, whereas digital devices display values as numbers and letters. A Lux meter may be portable or bench type.
Since light usually contains different colors and different wavelengths, the reading represents the combined effects of all the wavelengths. Typically, standard colors or color temperatures are expressed in degrees Kelvin (K).
If you are wondering what you should be looking into a lux meter. Then here’s a quick guide to a list of critical features you should look for before purchasing a lux meter.
The first thing you should be looking for is the accuracy of the lux meter. Precise analysis and accurate readings are critical, given the importance of quality light. Most lux meters can provide accuracy to around five lux. Higher cost models could offer to improve this level to 3 lux.
Next, of course, check out the cost of the lux meter. Look at the features of each model and analyze each lux meter properly. Cheaper lux meters might not offer the accuracy needed in your industry.
Lastly, look for its easy handling ability and portability. A lux meter’s size, easy handling, and portability are essential. It should ensure the safety of the instrument. The device should be small and very easy to operate.
Selecting lux meters or light measurement device requires certain performance specifications, including photocell, illumination range, Lux resolution, operating temperature, and foot-candle resolution. Special features include low battery Indicators, low voltage, alarms, remote light sensors, built-in memory, auto power-off, zero function, etc.
Importance Of Lux Meters
Lux meters are used in schools, public buildings, hospitals, workplaces, greenhouses, labs, industries, high sensitive areas, during construction, and production houses. They are also beneficial in monitoring light-sensitive displays in museums, art galleries, etc. They are extremely important for photographers, who work centered explicitly around light. They are also crucial in surgical theatres or other indoor environments such as offices.