Integrating Sphere for LED glow lamps PAR and PPF Testing

LED test instruments or LED Lamp Testing Equipment includes

• LPCE-2(LMS-9000) High Precision Spectroradiometer Integrating Sphere System.
• EN62471-C Optical Radiation Safety Test.
• LEDLM-80PL LED Optical Aging Test Instrument.
• LPCE-3 CCD Spectroradiometer Integrating Sphere Compact System.
• LSRF-3 Lamp Start, Run-up Time and Flicker Test System.

Plant Glow Lighting

Engineers have induced the plants to give off a dim light for nearly 4 hours. With further optimization, such plants will be bright enough to illuminate the entire workspace one day. Instead of switching on a lamp, you can easily read by the light of a glowing plant on your desk when it gets dark.

The aim of writing this article is to explain what these terms mean, do correction of some common misunderstandings and help the growers to understand how we can use the science behind these terms to determine proper light levels to grow happy, thriving plants.

What is PAR?

PAR stands for Photosynthetically Active Radiation (PAR). It’s the essential energy to produce the biomass, which directly affects the growth, development, yield, and quality of plants. PAR defines the type of light source that can support plant photosynthesis.

The light sources’ wavelength range that promotes green growth is wider than the photosynthetically active radiation wavelength range. It is roughly at the 300 nm to 800nm range. This part of the radiation is called physiological radiation. Apart from that, it can promote photosynthesis and affect other physiological activities.

The planting glow lighting needs to test PAR PPF; it requires a LISUN LPCE-2 system

When LEDs are available in the market, their tremendous efficiency and money-saving potential change the playing field and lumens, lux, and candela.

Recently, people started referring to PAR, PPF, and PPF as the best ways to measure light in photosynthetic lighting applications.

The PAR PPF is based on the following standards

Our LED fixtures emit extremely high PAR levels; PAR (Photosynthetically Active Radiation) is a much-used (and often misused) term. It describes the type of light needed to support photosynthesis in plant life. Photosynthesis enables plants to convert light energy into chemical energy. This energy is the food they use to grow and thrive.

As we all know, some light from candles is visible to the human eye, and infrared is not. Different types of light are defined by their “wavelengths”. These different wavelengths make up the electromagnetic radiation “spectrum.” The spectrum includes X-rays, radio waves, infrared light, and light that we can see, such as sunlight and light from a red or blue LED.

Interestingly, plants use the visible part of the spectrum to the human eye. Still, the wavelengths we perceive as the brightest (i.e., green light) are not the most efficient wavelengths for photosynthesis.
PAR is the part of the electromagnetic radiation spectrum (light).

It is helpful for plants and algae to activate photosynthesis; the point is PPF and PPFD. When we select a lighting system or fixture to promote photosynthesis, there are three measurement parameters that we should consider

•How much light the fixture produces.
• How much of that light is available to the plants.
• How much light the plant receives during the photoperiod.

Sphere integration

The inner surface of the sphere is coated with a highly diffused white coating. The beam enters the sphere through an opening. The inner surface is so highly diffused that the light is reflected multiple times in all the directions. This causes the light to be uniformly distributed around the entire inner surface of the sphere.

You can think of it as a diffuser but in three dimensions, there are many design details that need to be optimized for various applications including the size of the sphere, the type of the detector used, placing of internal baffles to prevent direct to prevent direct illumination of the detector by the source.

There is uniform distribution of the light inside the sphere. We can use a power sensor to sample a small part of the sphere’s inner surface. The power can be measured by knowing the area of the sensor and the surface area of the sphere. We can apply a calibration factor to get the total power in the sphere. This optical trick makes the readings independent of the beam size, position divergence.

Applications

We can use an integrating sphere to measure power from sources with widely diverging beams, such as LEDs, Vic CIL’s and other laser diodes, and fiber optics. Parallel laser beams can also be measured, taking advantage of the fact that the integrating sphere effectively attenuates the beam by having only a tiny fraction of it.

For example, we can use the fast response of a photodiode sensor and measure powers that, if directly incident on the photodiode, would saturate it.

Benefits of Integrating Sphere

•  The sphere is not able to misalign the beam.
•  Integrating spheres also have additional ports from which the light can be used for other uses—for example, performing spectral measurement or analyzing temporal pulse shape.
•  Integrating spheres can be used to measure the transmission or reflection of diffuse or scattering materials.
• Place the test sample at the entrance port of the sphere or a part opposite to the entrance port. It depends on the details of what you want to measure.
•  In addition, you can use the radiating spheres to measure the total light radiated from the lamp.
•  Integrating spheres is mainly used in optical measurements.
•  We can measure the total power of light without any inaccuracy. Apart from that, the reflection and absorption of samples can be easily understood.

LPEC-2(LMS-9000)Integrating Sphere Spectroradiometer System 

LPCE-2(LMS-9000) is a high CCD Spectroradiometer with good precision. It has a good Integration Sphere Testing System. It is best suitable for all luminaires’ photometric and colorimetric measurement such as energy-saving, fluorescent, and HID lamps. HID lamps are high voltage sodium pumps and mercury lamps with high voltage.

The measurements in the final data meet the requirements of CIE, EN, and LM-79 clause 9.1. These measurements are helpful for the measurement of photometry and colorimetry.

LPCE-2 Integrating Sphere Spectroradiometer LED Testing System is valid for single LEDs and LED lighting products light measurement. The quality of LEDs can be tested by analyzing their photometric, colorimetric, and electrical parameters.

System Configuration

•  Spectroradiometer (LMS-9000C) 
•  An Optical Fiber (CFO-1.5M)
•  Digital Power Meter (LS2050B)
•  DC Power source (DC3005)
•  AC Power source (LSP-500 VARC)
•  Integrating Sphere (IS-1.5MA and IS-0.3M)
•  A Standard Light Source (SLS-50W and SLS-10W)
•  19 Inch Cabinet (CASE-19IN)

Measurements

•  Colorimetric: Coordination of Chromaticity, CCT, Color Ratio, Peak Wavelength, Half Bandwidth
•  Photometric: Luminous Flux, Power radiancy, Energy Efficiency Class, EEI, Pupil Flux Efficiency, Pupil Factor, Cirtopic Flux and PPF
•  Electrical: Voltage, Current, Power, Power factor, and Displacement Factor
•  LED optical maintenance test: Flux VS Time, CCT VS time, CRI VS time, Power VS time, Power factor VS time, Current VS time, Flux efficiency VS time

Specification

•  Accuracy of Spectral Wavelength: 0.3 nm,
•  Reproducibility of Wavelength: 0.1nm
•  Sample Scanning Steps: 0.1 nm
•  Chromaticity Coordinate Accuracy: 0.002
•  Correlated Color Temperature: 1500~100,000 K
•  Accuracy: 0.3
•  Color Rendering Index Range: 0~100
•  Photometric Linear: 0.5
•  Time of integration: 0.1~10,000 ms
•  We can measure the temperature inside and outside of the integrating sphere
•  Flux testing methods include spectrum, photometric, and spectrum with the photometric revision
•  It includes an auxiliary lamp device
•  The software comprises a self-absorption function
•  It enables the download of the LM-79 Photometric, Colorimetric, and Electricity report in PDF. In addition, the LED Optical Maintenance test report can be exported to Excel or PDF.

LISUN Models	Wavelength
LMS-9000C	350-800 nm
LMS-9000 CUV-VIS	200-800 nm
LMS-9000 VIS-NIR	350-1050 nm

Frequently Asked Questions

What is the reason for using an integrating sphere?

An integrating sphere spreads the incoming light in different directions by reflecting the light over the entire surface of the sphere. This feature of an integrating sphere makes it an ideal instrument for multiple applications. For example, laser power, reflectance, flux, and other radiance instruments.

What are the drawbacks of an integrating sphere?

Apart from the advantages of an integrating sphere, there are some disadvantages. The coating gets damaged if the source of light is high-powered. We can not use the damaged layer; it should be changed if we use the sphere again. This is an expensive task. Materials used in this procedure are barium sulphate and magnesium oxide.

Lisun Instruments Limited was found by LISUN GROUP in 2003. LISUN quality system has been strictly certified by ISO9001:2015. As a CIE Membership, LISUN products are designed based on CIE, IEC and other international or national standards. All products passed CE certificate and authenticated by the third party lab.

Our main products are Goniophotometer, Integrating Sphere, Spectroradiometer, Surge Generator, ESD Simulator Guns, EMI Receiver, EMC Test Equipment, Electrical Safety Tester, Environmental Chamber, Temperature Chamber, Climate Chamber, Thermal Chamber, Salt Spray Test, Dust Test Chamber, Waterproof Test, RoHS Test (EDXRF), Glow Wire Test and Needle Flame Test.

Please feel free to contact us if you need any support.
Tech Dep: Service@Lisungroup.com, Cell/WhatsApp:+8615317907381
Sales Dep: Sales@Lisungroup.com, Cell/WhatsApp:+8618117273997

Tags：LMS-6000 , LPCE-2(LMS-9000)