Understanding the Difference Between PAR Meter, Spectrometer & LUX Meter

What is the difference between PAR meter, Spectrometer and LUX meter

Why can’t we use LUX value for plant lighting?

This is the common question customer ask on regular basis.

Before giving any answer, first let’s understand basic of light obsobation pattern for human and plants. In human eyes absorb light and in plant leaves absorb light.

Kindly check below The McCree curve, overlaid with PAR and Lumens as represented by their comparative measure of intensity across the spectrum.

McCree curve represent the plant light absorption pattern in light spectrum.

PAR is the region between 400 nm to 700 nm which is also known as visible spectrum. In PAR region you can see plants absorb more blue (420-460) and red (620-660) compared with middle green region (500-600). Where as Human eyes absorb more green region (500-600) compared with other parts.

So, for plants PAR is important and for human Lumen is important.

PAR meter measure PPFD and Lumen meter (also known as LUX meter) measure LUX.

We hope that, now you got the answer of your question.

McCree curve represent the plant light absorption pattern in light spectrum.

So, for plants PAR is important and for human Lumen is important.

PAR meter measure PPFD and Lumen meter (also known as LUX meter) measure LUX.

We hope that, now you got the answer of your question.

Spectrometer, PAR Meter, and LUX Meter are the devices used to carry out quantitative analysis of any incident light in their respective units. While they all measure the intensity of light, there are some key differences between them.

Spectrometer:

A spectrometer is a high-end device that measures the entire spectrum of light, including its intensity and spectrum. It is a costly instrument because it uses advanced technology to break down light into its individual wavelengths, allowing you to measure the exact amount of each wavelength present in the light. Spectrometers are commonly used in industries where precise measurements of light quality and intensity are essential.

Nexsel has best spectrometer in India, kindly check product section for more information.

PAR Meter:

A PAR (Photosynthetically Active Radiation) meter is a more affordable device that gives only quantitative measurements specifically of the wavelengths of light that are essential for plant growth (400 nm to 700 nm). PAR meters do not measure the full spectrum of light but instead focus on the specific wavelengths of light that plants need for photosynthesis. This makes them a popular tool for horticulturists and indoor gardeners to ensure that their plants are receiving the right amount and quality of light.

PAR measure PPFD, unit of PPFD is umol/m2/sec

PAR meter in India – Our team is working on to develop most cost-effective PAR meter for Indian market.

LUX Meter :

A LUX meter, on the other hand, is a device used to measure the illuminance of light. It measures the amount of light that falls on a surface and is used to determine the appropriate lighting levels for different applications. For example, in interior design, a LUX meter can be used to determine the appropriate lighting levels for a room to ensure that it is well-lit but not too bright or too dim for human eyes. LUX meters are more affordable than spectrometers and PAR meters and are commonly used in industries such as architecture, film production, and photography.

Frequently asked question is can we measure light intensity for plants in LUX? To answer this question, we can say LUX is not right measurement for plant lighting. Just for reference we can use or we can use by with LUX to PPFD correction factor.